Publications

2016
Hetem DJ, Derde LPG, Empel J, Mroczkowska A, Orczykowska-Kotyna M, Kozińska A, Hryniewicz W, Goossens H, Bonten MJM. Molecular epidemiology of MRSA in 13 ICUs from eight European countries. J Antimicrob Chemother. 2016;71(1):45-52.Abstract
OBJECTIVES: The European epidemiology of MRSA is changing with the emergence of community-associated MRSA (CA-MRSA) and livestock-associated MRSA (LA-MRSA). In this study, we investigated the molecular epidemiology of MRSA during 2 years in 13 ICUs in France, Greece, Italy, Latvia, Luxemburg, Portugal, Slovenia and Spain. METHODS: Surveillance cultures for MRSA from nose and wounds were obtained on admission and twice weekly from all patients admitted to an ICU for ≥3 days. The first MRSA isolate per patient was genotyped in a central laboratory by MLST, spa typing, agr typing and SCCmec (sub)typing. Risk factors for patients with an unknown history of MRSA colonization were identified. RESULTS: Overall, 14 390 ICU patients were screened, of whom 8519 stayed in an ICU for ≥3 days. Overall MRSA admission prevalence was 3.9% and ranged from 1.0% to 7.0% for individual ICUs. Overall MRSA acquisition rate was 2.5/1000 patient days at risk and ranged from 0.2 to 8/1000 patient days at risk per ICU. In total, 557 putative MRSA isolates were submitted to the central laboratory for typing, of which 511 (92%) were confirmed as MRSA. Each country had a distinct epidemiology, with ST8-IVc (UK-EMRSA-2/-6, USA500) being most prevalent, especially in France and Spain, and detected in ICUs in five of eight countries. Seventeen (3%) and three (<1%) isolates were categorized as CA-MRSA and LA-MRSA, respectively. Risk factors for MRSA carriage on ICU admission were age >70 years and hospitalization within 1 year prior to ICU admission. CONCLUSIONS: The molecular epidemiology of MRSA in 13 European ICUs in eight countries was homogeneous within, but heterogeneous between, countries. CA-MRSA and LA-MRSA genotypes and Panton-Valentine leucocidin-producing isolates were detected sporadically.
2015
Metaxas EI, Balis E, Papaparaskevas J, Spanakis N, Tatsis G, Tsakris A. Bronchiectasis exacerbations: The role of atypical bacteria, respiratory syncytial virus and pulmonary function tests. Can Respir J. 2015;22(3):163-6.Abstract
BACKGROUND: Aside from the known role of common bacteria, there is a paucity of data regarding the possible role of atypical bacteria and viruses in exacerbations of non-cystic fibrosis bronchiectasis. OBJECTIVE: To explore the possible role of atypical bacteria (namely, Mycoplasma pneumoniae and Chlamydophila pneumoniae) and respiratory syncytial virus (RSV) as causative agents of bronchiectasis exacerbations. METHODS: A cohort of 33 patients was studied over a two-year period (one year follow-up for each patient). Polymerase chain reaction for the detection of M pneumoniae, C pneumoniae and RSV in bronchoalveolar lavage samples were performed during all visits. Antibody titres (immunoglobulin [Ig]M and IgG) against the aforementioned pathogens were also measured. In addition, cultures for common bacteria and mycobacteria were performed from the bronchoalveolar lavage samples. RESULTS: Fifteen patients experienced a total of 19 exacerbations during the study period. Although RSV was detected by polymerase chain reaction during stable visits in four patients, it was never detected during an exacerbation. M pneumoniae and C pneumoniae were never detected at stable visits or during exacerbations. IgM antibody titres for these three pathogens were negative in all patient visits. CONCLUSIONS: Atypical pathogens and RSV did not appear to be causative agents of bronchiectasis exacerbations.
Dautzenberg MJD, Wekesa AN, Gniadkowski M, Antoniadou A, Giamarellou H, Petrikkos GL, Skiada A, Brun-Buisson C, Bonten MJM, Derde LPG. The association between colonization with carbapenemase-producing enterobacteriaceae and overall ICU mortality: an observational cohort study. Crit Care Med. 2015;43(6):1170-7.Abstract
OBJECTIVES: Infections caused by carbapenemase-producing Enterobacteriaceae are increasing worldwide, especially in ICUs, and have been associated with high mortality rates. However, unequivocally demonstrating causality of such infections to death is difficult in critically ill patients because of potential confounding and competing events. Here, we quantified the effects of carbapenemase-producing Enterobacteriaceae carriage on patient outcome in two Greek ICUs with carbapenemase-producing Enterobacteriaceae endemicity. DESIGN: Observational cohort study. SETTING: Two ICUs with carbapenemase-producing Enterobacteriaceae endemicity. PATIENTS: Patients admitted to the ICU with an expected length of ICU stay of at least 3 days were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Carbapenemase-producing Enterobacteriaceae colonization was established through screening in perineum swabs obtained at admission and twice weekly and inoculated on chromogenic plates. Detection of carbapenemases was performed phenotypically, with confirmation by polymerase chain reaction. Risk factors for ICU mortality were evaluated using cause-specific hazard ratios and subdistribution hazard ratios, with carbapenemase-producing Enterobacteriaceae colonization as time-varying covariate. One thousand seven patients were included, 36 (3.6%) were colonized at admission, and 96 (9.5%) acquired carbapenemase-producing Enterobacteriaceae colonization during ICU stay, and 301 (29.9%) died in ICU. Of 132 carbapenemase-producing Enterobacteriaceae isolates, 125 (94.7%) were Klebsiella pneumoniae and 74 harbored K. pneumoniae carbapenemase (56.1%), 54 metallo-β-lactamase (40.9%), and four both (3.0%). Carbapenemase-producing Enterobacteriaceae colonization was associated with a statistically significant increase of the subdistribution hazard ratio for ICU mortality (subdistribution hazard ratio=1.79; 95% CI, 1.31-2.43), not explained by an increased daily hazard of dying (cause-specific hazard ratio for death=1.02; 95% CI, 0.74-1.41), but by an increased length of stay (cause-specific hazard ratio for discharge alive=0.73; 95% CI, 0.51-0.94). Other risk factors in the subdistribution hazard model were Acute Physiology and Chronic Health Evaluation II score (subdistribution hazard ratio=1.13; 95% CI, 1.11-1.15), female gender (subdistribution hazard ratio=1.29; 95% CI, 1.02-1.62), presence of solid tumor (subdistribution hazard ratio=1.54; 95% CI, 1.15-2.06), hematopoietic malignancy (subdistribution hazard ratio=1.61; 95% CI, 1.04-2.51), and immunodeficiency (subdistribution hazard ratio=1.59; 95% CI, 1.11-2.27). CONCLUSIONS: Patients colonized with carbapenemase-producing Enterobacteriaceae have on average a 1.79 times higher hazard of dying in ICU than noncolonized patients, primarily because of an increased length of stay.
Giannopoulos L, Papaparaskevas J, Refene E, Daikos G, Stavrianeas N, Tsakris A. MLST typing of antimicrobial-resistant Propionibacterium acnes isolates from patients with moderate to severe acne vulgaris. Anaerobe. 2015;31:50-4.Abstract
Molecular typing data on antimicrobial-resistant Propionibacterium strains are limited in the literature. We examined antimicrobial resistance profiles and the underlying resistance mechanisms in Propionibacterium spp. isolates recovered from patients with moderate to severe acne vulgaris in Greece. The clonallity of the resistant Propionibacterium acnes isolates was also investigated. Propionibacterium spp. isolates were detected using Tryptone-Yeast Extract-Glucose (TYG) agar plates supplemented with 4% furazolidone. Erythromycin, clindamycin, vancomycin, penicillin, co-trimoxazole, doxycycline, minocycline and ciprofloxacin MICs were determined using the gradient strip method. Erythromycin, clindamycin and tetracycline mechanisms of resistance were determined using PCR and sequencing of the domain V of 23S rRNA and 16S rRNA, as well as the presence of the ermX gene. Typing was performed using the multi locus sequence typing (MLST) methodology. Seventy nine isolates from 76 patients were collected. Twenty-three isolates (29.1%) exhibited resistance to erythromycin and clindamycin, while two additional isolates (2.5%) were resistant only to erythromycin. Resistance to tetracycline was not detected. The underlying molecular mechanisms were point mutations A2059G and A2058G. MLST typing of the P. acnes resistant isolates revealed that lineage type IA1 (ST-1, 3 and 52) prevailed (12/18; 66.7%), whilst lineage type IA2 (ST-2 and 22) accounted for five more isolates (27.8%). Susceptible isolates were more evenly distributed between ST types. Propionibacterium spp. from moderate to severe acne vulgaris in Greece are frequently resistant to erythromycin/clindamycin but not to tetracyclines, mainly due to the point mutations A2059G and A2058G. P. acnes resistant isolates were more clonally related than susceptible ones and belonged to a limited number of MLST types.
Chatziioannou S, Papamichos O, Gamaletsou MN, Georgakopoulos A, Kostomitsopoulos NG, Tseleni-Balafouta S, Papaparaskevas J, Walsh TJ, Pneumaticos SG, Sipsas NV. 18-Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography scan for monitoring the therapeutic response in experimental Staphylococcus aureus foreign-body osteomyelitis. J Orthop Surg Res. 2015;10:132.Abstract
BACKGROUND: 18-Fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography ((18)F-FDG PET/CT) scan is useful for diagnosis of osteoarticular infections. Whether (18)F-FDG PET/CT scanning may be used for therapeutic monitoring is not clear. The objective of this study was to develop (18)F-FDG PET/CT scanning for monitoring therapeutic response to antimicrobials in experimental Staphylococcus aureus osteomyelitis. METHODS: A total of 22 rabbits were studied. In 20 animals, the right tibia was inoculated intraoperatively with S. aureus. Two control animals were inoculated with normal saline. A needle was placed in the tibia as a foreign body. Infection was allowed to develop for 21 days when (18)F-FDG PET/CT was performed, the needle was removed, and bone specimens were cultured to confirm infection. Antimicrobial therapy with daptomycin was initiated in all successfully infected animals for 1, 3, or 6 weeks. Following completion of treatment, a second (18)F-FDG PET/CT was performed, animals were euthanized, and infected tibias were harvested for quantitative cultures and histology. A positive scan was defined as (18)F-FDG signal activity greater in the infected tibia than that of the contralateral non-infected control tibia. Therapeutic response was measured by the change of (18)F-FDG signal activity in the infected tibia. RESULTS: All successfully infected animals (n = 14), with microbiologically and/or histologically confirmed osteomyelitis, had positive (18)F-FDG PET/CT scans, while the two control animals had negative scans despite the presence of the foreign body [mean maximum standardized uptake value (SUVmax) (±SD) values 2.96 (±0.80) vs. 1 (±1.10), respectively, P = 0.04]. In the 14 successfully infected animals, the mean SUVmax was significantly higher in the infected compared to the uninfected tibia (P < 0.0001). A SUVmax of 1.4, when used as a cutoff for infection, yielded a diagnostic accuracy of 93 %. At the end of treatment, successfully treated animals and saline controls had a negative (18)F-FDG PET/CT scan (n = 4), while animals with persistent infection despite treatment (n = 12) had a positive (18)F-FDG PET/CT scan (SUVmax 1.0-3.0) (p < 0.001). SUVmax values were significantly reduced after 42 days of treatment from 3.15 ± 0.5 (day 7) to 1.71 ± 0.37 (day 42) (p = 0.05). CONCLUSIONS: (18)F-FDG PET/CT scan is a sensitive and specific tool in therapeutic monitoring of experimental foreign-body osteomyelitis.
2014
Zachariadou L, Stathi A, Tassios PT, Pangalis A, Legakis NJ, Papaparaskevas J. Differences in the epidemiology between paediatric and adult invasive Streptococcus pyogenes infections. Epidemiol Infect. 2014;142(3):512-9.Abstract
In order to investigate for possible differences between paediatric and adult invasive Streptococcus pyogenes (iGAS) infections, a total of 142 cases were identified in 17 Greek hospitals during 2003-2007, of which 96 were children and 46 adults. Bacteraemia, soft tissue infections, streptococcal toxic shock syndrome (STSS), and necrotizing fasciitis were the main clinical presentations (67·6%, 45·1%, 13·4%, and 12·0% of cases, respectively). Bacteraemia and lymphadenitis were significantly more frequent in children (P=0·019 and 0·021, respectively), whereas STSS was more frequent in adults (P=0·017). The main predisposing factors in children were varicella and streptococcal pharyngotonsillitis (25% and 19·8%, respectively), as opposed to malignancy, intravenous drug abuse and diabetes mellitus in adults (19·6%, 15·2% and 10·9%, respectively). Of the two dominant emm-types, 1 and 12 (28·2% and 8·5%, respectively), the proportion of emm-type 12 remained stable during the study period, whereas emm-type 1 rates fluctuated considerably. Strains of emm-type 1 from children were associated with erythromycin susceptibility, STSS and intensive-care-unit admission, whereas emm-type 12 isolates from adults were associated with erythromycin and clindamycin resistance. Finally, specific emm-types were detected exclusively in adults or in children. In conclusion, several clinical and epidemiological differences were detected, that could prove useful in designing age-focused strategies for prevention and treatment of iGAS infections.
Papaparaskevas J, Stathi A, Alexandrou-Athanassoulis H, Charisiadou A, Petropoulou N, Tsakris A, Valari M. Pitted keratolysis in an adolescent, diagnosed using conventional and molecular microbiology and successfully treated with fusidic acid. Eur J Dermatol. 2014;24(4):499-500.
Zegaer BH, Ioannidis A, Babis GC, Ioannidou V, Kossyvakis A, Bersimis S, Papaparaskevas J, Petinaki E, Pliatsika P, Chatzipanagiotou S. Detection of Bacteria Bearing Resistant Biofilm Forms, by Using the Universal and Specific PCR is Still Unhelpful in the Diagnosis of Periprosthetic Joint Infections. Front Med (Lausanne). 2014;1:30.Abstract
Intraoperative conventional bacteriological cultures were compared with different polymerase chain reaction (PCR) methods in patients with total joint arthroplasties. The isolated bacteria were investigated for biofilm formation, and the biofilm forming strains, in their planktonic and biofilm forms, were further tested for their antimicrobial resistance against several clinically important antimicrobials. Forty four bone and joint samples were included and classified as infected or non-infected according to standard criteria for periprosthetic hip and knee infections. For the bacteriological diagnosis, conventional culture, two types of universal PCR and species specific PCR for three selected pathogens (Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa) were applied. Biofilm formation determination was performed by the tissue culture plate method. Antimicrobial susceptibility of the planktonic bacteria was performed by the minimal inhibitory concentration determination and, of the biofilm forms, by the minimal inhibitory concentration for bacterial regrowth from the biofilm. Twenty samples were culture positive, with S. epidermidis, S. aureus, or P. aeruginosa. All PCR methods were very ineffective in detecting only one pathogen. All isolates were biofilm positive and their biofilm forms, were highly resistant. In this study, compared to PCR, culture remains the "gold standard." The biofilm formation by the causative bacteria and the concomitant manifold increased antimicrobial resistance may explain the clinical failure of treatment in some cases and should be considered in the future for therapeutic planning.
Nakou A, Papaparaskevas J, Diamantea F, Skarmoutsou N, Polychronopoulos V, Tsakris A. A prospective study on bacterial and atypical etiology of acute exacerbation in chronic obstructive pulmonary disease. Future Microbiol. 2014;9(11):1251-60.Abstract
AIM: The bacterial and atypical etiology of acute exacerbations of chronic obstructive pulmonary disease was investigated and the diagnostic techniques used were compared among 92 hospitalized patients. MATERIALS & METHODS: Sputum specimens were investigated using culture and PCR, serological status evaluation was performed and the inflammatory profile was associated with the microbiological results. RESULTS & CONCLUSION: The majority of the patients (65.2%) had very severe airway obstruction. The most common bacteria were Haemophilus influenzae and Pseudomonas aeruginosa (23.9 and 14.1%, respectively). Acinetobacter baumannii- and P. aeruginosa-positive cultures were associated with prolonged hospitalization and severe airway obstruction (p = 0.03 and 0.031, respectively). Chlamydia pneumoniae or Mycoplasma pneumoniae infection was diagnosed in four and two patients, respectively. Discrepant results were detected between PCR and serology, especially regarding C. pneumoniae.
2013
Papaparaskevas J, Mela V, Houhoula DP, Pantazatou A, Petrikkos GL, Tsakris A. Comparative evaluation of conventional and real-time PCR assays for detecting Bacteroides fragilis in clinical samples. J Clin Microbiol. 2013;51(5):1593-5.Abstract
A conventional PCR and a real-time PCR for detecting Bacteroides fragilis were evaluated against clinical specimens. Analytical sensitivities were 100 and 40 fg of DNA, respectively. Detection limits were 100 and 10 CFU/ml, respectively. A total of six culture-negative specimens were positive by PCR. Altering the gold standard from "positive culture" to "positive culture or both PCR assays positive" resulted in sensitivities of 91.7% and 100%, respectively, and in specificities of 100% and 98.6%, respectively.
Eitel Z, Sóki J, Urbán E, Nagy E. The prevalence of antibiotic resistance genes in Bacteroides fragilis group strains isolated in different European countries. Anaerobe. 2013;21:43-9.Abstract
From the 2008-2009 European Bacteroides antibiotic resistance survey, we selected 161 strains for detection of antibiotic resistance genes (cepA, cfxA, cfiA, nim, ermB, ermF, ermG, linA, mefA, msrSA, tetM, tetQ, tetX, tetX1, tet36 and bexA). To facilitate the throughput, the genes were detected by Real-Time PCR. The presence of the genes was correlated with the known MIC data of the strains for the appropriate antibiotics. For the β-lactams, the cepA gene was found in 70.8% of the tested strains (all resistant to ampicillin), but its presence did not correlate with the ampicillin MIC values. The cepA gene occurred at different frequencies among Bacteroides fragilis and non-fragilis Bacteroides strains. The cfxA gene was not a major factor in determining cefoxitin resistance and it was found with higher prevalence in non-fragilis Bacteroides strains than in B. fragilis. Among the five possible clindamycin resistance genes, ermF was the most common and had the highest effect on clindamycin resistance after linA. The ermG-mefA-msrSA combination was found in a set of strains and their linked occurrence implied that they were harbored by the conjugative transposon CTnGERM1. All strains tested were susceptible to metronidazole and none of them harbored nim genes. TetQ was prevalent among both the B. fragilis and non-fragilis Bacteroides strains (78.9 and 84.8%, respectively) and no gene could be clearly linked to tigecycline resistance other than tetQ. BexA, which codes for the fluoroquinolone efflux pump, was found in 7.5% of strains and occurred at different frequencies among B. fragilis and non-fragilis Bacteroides strains, but was represented only in a minor proportion of moxifloxacin-resistant strains.
Polyzois G, Stefaniotis T, Papaparaskevas J, Donta C. Antimicrobial efficacy of denture adhesives on some oral malodor-related microbes. Odontology. 2013;101(1):103-7.Abstract
The objective of the study was to determine the antimicrobial efficacy of three denture adhesives toward Streptococcus oralis, mutans, Prevotella oralis and Fusobacterium nucleatum. Adhesives used were Corega Ultra(®), Fixodent Pro Original(®) and Biotene(®) Denture Grip. For Streptococcus oralis and Streptococcus mutans, four tubes of Trypticase Soy Broth 10 mL and 1 g denture of adhesive were used. In addition four tubes of Trypticase Soy Broth 10 mL without any denture adhesive was employed as control. For Prevotella oralis and Fusobacterium nucleatum, four tubes of thioglycolate 10 mL and 1 g denture adhesive were used for each one, while four tubes of thioglycolate 10 mL without adhesive served as control. All samples were incubated for 48 h at 37°C. After 48 h, the number of colonies was counted and the mean was extracted as cfu/mL. The results were evaluated with ANOVA on ranked data and Tukey's post hoc test at α = 0.05. Streptococcus oralis, mutans, Prevotella oralis and Fusobacterium nucleatum showed decreased number of colonies for each denture adhesive compared to the control. Under the conditions of this in vitro study, all the tested denture adhesives showed antimicrobial efficacy. However, in contrast to the hypothesis, there were differences among them. Corega Ultra(®) and Biotene(®) Denture Grip were more effective for all the tested oral malodor-related microbes than Fixodent Pro Original(®).
Sóki J, Eitel Z, Urbán E, Nagy E. Molecular analysis of the carbapenem and metronidazole resistance mechanisms of Bacteroides strains reported in a Europe-wide antibiotic resistance survey. Int J Antimicrob Agents. 2013;41(2):122-5.Abstract
Here we examine the carbapenem and metronidazole resistance mechanisms of 640 Bacteroides strains reported in the 2008-2009 European antibiotic susceptibility survey. Of the 22 strains with elevated imipenem minimum inhibitory concentrations (≥4 μg/mL), 10 were cfiA-positive and out of these 5 carried activating insertion sequence (IS) elements in the upstream regions of the cfiA genes. However, resistant strains with cfiA genes but with no activating IS elements were found (n=2) as well as a resistant strain with no cfiA gene. In the former the resistance phenotypes by Etest were heterogeneous, whilst in the latter no carbapenemase production was seen; both mechanisms have been rarely observed, examined and characterised. Interestingly, few (n=3) nim-positive strains were found, including one metronidazole-resistant strain harbouring nimE activated by ISBf6, and two susceptible strains harbouring chromosomally located nim genes.
Serelis J, Papaparaskevas J, Stathi A, Sawides AL, Karagouni AD, Tsakris A, Pangalis A. Granulomatous infection of the hand and wrist due to Azospirillum spp. Diagn Microbiol Infect Dis. 2013;76(4):513-5.Abstract
We report a case of Azospirillum infection manifestating as granulomatous tenosynovitis of the right hand, in an immunocompetent middle-aged female. We highlight the unusual source of the infection, the diagnostic workup, as well as the treatment approach.
2012
Houhoula DP, Peirasmaki D, Konteles SJ, Kizis D, Koussissis S, Bratacos M, Poggas N, Charvalos E, Tsakris A, Papaparaskevas J. High level of heterogeneity among Listeria monocytogenes isolates from clinical and food origin specimens in Greece. Foodborne Pathog Dis. 2012;9(9):848-52.Abstract
In order to examine the genetic variation of clinical and food isolates of Listeria monocytogenes in Greece, a total of 61 L. monocytogenes non-duplicate isolates, recovered from clinical specimens (n=19) and food (n=42), were serotyped and genotyped using two different Random Amplification of Polymorphic DNA (RAPD) protocols and Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Serotype group 4b, 4d, 4e prevailed (39.4%), among both clinical and food isolates, followed by serotype group 1/2a, 3a (23.0%), which nevertheless was detected only among food isolates. The most discriminatory typing protocol was MLVA, which grouped four isolates into two pairs, while the remaining isolates produced unique fingerprints. Similar results were obtained when taking into account the combination of the two RAPD protocols (Simpson index 0.999); six isolates were grouped into three pairs, two of which were the pairs that were identified also by MLVA. Single use of each RAPD protocol resulted in inferior discrimination (Simpson index 0.978 and 0.997, respectively). In conclusion, the two molecular procedures, MLVA, and the combined RAPD protocols, produced similar results, showing that L. monocytogenes isolates from clinical and food specimens were highly heterogenous and that clustering was very uncommon.
Tarpatzi A, Avlamis A, Papaparaskevas J, Daikos GL, Stefanou I, Katsandri A, Vasilakopoulou A, Chatzigeorgiou KS, Petrikkos GL. Incidence and risk factors for central vascular catheter-related bloodstream infections in a tertiary care hospital. New Microbiol. 2012;35(4):429-37.Abstract
This study evaluated the incidence of colonization and infection related to Central Vascular Catheters (CVC) in a tertiary care Greek hospital, as well as risk factors associated with catheter-related bloodstream infection (CRBSI). A total of 340 CVCs, were studied in relation to patient clinical and epidemiological data, CVC characteristics, and microbiological culture results. Risk factors were assessed. Pulsed field gel electrophoresis was used for the investigation of the clonal relationship of the isolates. The incidence for CRBSI and catheter colonization (CC) was 11.47 and 19.49 per 1,000 catheter days, respectively. Risk factors independently associated with CRBSI were use of corticosteroids, diabetes mellitus, solid organ neoplasm, long duration of catheterization, and changing the CVC dressing at intervals of 48 hours or more. Risk factors for CC were diabetes mellitus, hospitalization in ICU, and prolonged hospitalization. The predominant microorganisms isolated from CRBSI episodes were coagulase-negative staphylococci. All patients with CVC require constant infection surveillance and appropriate care by trained medical staff. Use of CVC for the shortest time possible, good hand hygiene and change of CVC dressing at intervals of less than 48 hours are infection prevention practices that need to be followed.
Stefos A, Gatselis N, Goudelas A, Mpakarosi M, Papaparaskevas J, Dalekos G, Petinaki E. Cutaneous infection caused by Bacillus anthracis in Larissa, Thessaly, Central Greece, July 2012. Euro Surveill. 2012;17.Abstract
In July 2012, a confirmed case of cutaneous anthraxinfection in a stockbreeder in the prefecture of Larissa, Thessaly, Central Greece was reported. The investigation revealed five related deaths in animals (two dogs and three sheep). Control measures have been taken immediately in order to prevent further spread in humans and animals.
2011
Nordmann P, Picazo JJ, Mutters R, Korten V, Quintana A, Laeuffer JM, Seak JCH, Flamm RK, Morrissey I. Comparative activity of carbapenem testing: the COMPACT study. J Antimicrob Chemother. 2011;66(5):1070-8.Abstract
OBJECTIVES: Doripenem is a new carbapenem recently introduced into Europe. The COMParative Activity of Carbapenem Testing (COMPACT) study compared the susceptibility of common Gram-negative bacilli causing serious infections in hospitalized patients with doripenem, imipenem and meropenem. METHODS: Gram-negative isolates (4498 total: 2171 Pseudomonas species; 1910 Enterobacteriaceae; and 417 other Gram-negative bacilli) were collected from 80 centres in 16 countries in Europe, the Middle East and Africa during 2008-09. The MICs of doripenem, imipenem and meropenem were determined using Etest methodology and broth microdilution. Susceptibility was interpreted according to CLSI, EUCAST and FDA breakpoints. RESULTS: The MIC(90)s of doripenem, imipenem and meropenem for all isolates were 8, ≥64 and 32 mg/L, respectively. Doripenem had the lowest MIC(90) for Pseudomonas species at 16 mg/L, with imipenem and meropenem values of ≥64 mg/L. Enterobacteriaceae were highly susceptible to all three carbapenems, with MIC(90)s of doripenem, imipenem and meropenem of 0.06, 0.5 and 0.12 mg/L, respectively. Other Gram-negative isolates, predominantly Acinetobacter baumannii, were resistant to all three carbapenems (MIC(90) ≥64 mg/L). Susceptibility to doripenem was observed in 14.9% of isolates resistant to imipenem and/or meropenem. CONCLUSIONS: Doripenem showed excellent activity against Gram-negative isolates; generally it was more active than imipenem and at least as good as meropenem. Against Pseudomonas species, doripenem was more active than both imipenem and meropenem, with doripenem susceptibility observed for some imipenem- and/or meropenem-resistant isolates.
Nagy E, Urbán E, Nord CE. Antimicrobial susceptibility of Bacteroides fragilis group isolates in Europe: 20 years of experience. Clin Microbiol Infect. 2011;17(3):371-9.Abstract
The susceptibilities of 824 Bacteroides fragilis group isolates against nine antibiotics were evaluated in a Europe-wide study involving 13 countries. Species determination, by different methods, was carried out on all but one isolate. Resistance rates were evaluated according to species and geographical areas via CLSI and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints. The present data were compared with those obtained 10 and 20 years ago at a European level. High-level resistance (MIC ≥ 64 mg/L) to ampicillin was observed in 44.5% of the strains, which is a significant increase relative to 20 years ago (16%). Piperacillin/tazobactam was more active than amoxicillin/clavulanic acid (3.1% and 10.4% resistance, respectively), again with a resistance increase relative to earlier studies. Dramatic increases in resistance were observed for cefoxitin, clindamycin and moxifloxacin, with rates of 17.2%, 32.4% and 13.6%, respectively. The lowest resistances were found for imipenem, metronidazole and tigecycline (1.2%, <1% and 1.7%). Nonsusceptible strains to imipenem and metronidazole were more resistant to other anti-anaerobic drugs. Differences were detected between geographical areas, with higher resistance rates for moxifloxacin in Scandinavian countries (21.4%) than in Mediterranean countries (5.4%), whereas, for clindamycin, the resistance rates were higher in Mediterranean (41.8%) and lower in Scandinavian countries (22.5%). Piperacillin/tazobactam resistance was also higher in Scandinavian countries.
Siatelis A, Houhoula DP, Papaparaskevas J, Delakas D, Tsakris A. Detection of bacillus Galmette-Guérin (Mycobacterium bovis BCG) DNA in urine and blood specimens after intravesical immunotherapy for bladder carcinoma. J Clin Microbiol. 2011;49(4):1206-8.Abstract
A real-time PCR targeting IS6110 was employed for the detection of Mycobacterium tuberculosis DNA in specimens collected from 10 patients treated with intravesical M. bovis bacillus Galmette-Guérin (BCG) immunotherapy for bladder malignancy. BCG DNA was detected in all urine specimens taken 24 h after the instillations, as well as in 24% of the specimens collected 7 days after the instillations; it was also detected in a single specimen taken 6 weeks after the last instillation. BCG DNA was detected in 8.3% of the blood specimens taken 1 day after instillation, and its amplification was associated with cases of self-limiting fever. These findings give indications that this real-time PCR is helpful to recognize BCG bacteremic cases, which may lead to mycobacterial infection.
Papaparaskevas J, Katsandri A, Pantazatou A, Stefanou I, Avlamis A, Legakis NJ, Tsakris A. Epidemiological characteristics of infections caused by Bacteroides, Prevotella and Fusobacterium species: a prospective observational study. Anaerobe. 2011;17(3):113-7.Abstract
In order to investigate differences among infections due to Gram-negative anaerobic bacteria (Bacteroides, Prevotella and Fusobacterium spp.), clinical, epidemiological, and microbiological data were collected and evaluated from 206 anaerobic infections. The most frequently isolated species was Bacteroides fragilis. The majority of the cases were intra-abdominal infections (49%) followed by skin and soft tissue infections (24.7%). Logistic regression analysis showed that Bacteroides spp. strains were more often isolated from intra-abdominal infections (p = 0.002), whereas Prevotella spp. were isolated more frequently from cases with shorter duration of hospitalization (p = 0.026), and less frequently from bloodstream infections (p = 0.049). In addition, Bacteroides spp. were associated with coinfection due to Enterobacteriaceae species (p = 0.007), whereas Prevotella spp. were associated with coinfection due to Staphylococcus spp. (p = 0.002). Patients with an infection due to B. fragilis, were more frequently admitted in a general surgical ward (p = 0.017), or have been treated with a 2nd generation cephalosporin before anaerobic infection onset (p = 0.05). Total mortality was 10.9% and was associated with bacteremia (p = 0.026), and hematological (p = 0.028), or solid organ malignancy (p = 0.007). Metronidazole resistance was detected only among Prevotella spp. (16.2%) and B. fragilis group (0.8%) isolates. In conclusion, this study indicated differences between infections due to the most frequently isolated Gram-negative anaerobic species, differences that may affect the design and implementation of empirical antimicrobial chemotherapy guidelines.
2010
Papadogeorgakis H, Pittaras TE, Papaparaskevas J, Pitiriga V, Katsambas A, Tsakris A. Chlamydia trachomatis serovar distribution and Neisseria gonorrhoeae coinfection in male patients with urethritis in Greece. J Clin Microbiol. 2010;48(6):2231-4.Abstract
The distribution of Chlamydia trachomatis serovars and Neisseria gonorrhoeae coinfection was studied in a group of 100 C. trachomatis-positive males with urethritis in Greece. The serovar distribution revealed that apart from the predominant worldwide types E and F, the relatively uncommon type G is also prevalent. Gonococcal coinfection was frequent (30%) and was associated with genovariant Ja (75%, P = 0.008).
Papaparaskevas J, Tzouvelekis LS, Tsakris A, Pittaras TE, Legakis NJ. In vitro activity of tigecycline against 2423 clinical isolates and comparison of the available interpretation breakpoints. Diagn Microbiol Infect Dis. 2010;66(2):187-94.Abstract
MICs to tigecycline and 12 antimicrobials were performed by microdilution method, against 2423 nonduplicate pathogens recently isolated in 17 Greek hospitals. The Food and Drug Administration (FDA) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria were used comparatively for interpretation of tigecycline MICs. Tigecycline exhibited potent in vitro activity against the majority of the isolates tested. (MIC(90) values of 0.5, 1, 2, 0.125, 1, 0.25, 0.125, and 1 mg/L were observed for Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., Moraxella catarrhalis, Acinetobacter spp., Staphylococcus aureus, Enterococcus spp., and Streptococcus pneumoniae isolates, respectively.) Tigecycline activity was the same, irrespective of the resistance profile to other antimicrobials (Gram-negative pathogens susceptible or resistant to imipenem, Enterococcus spp., S. aureus, or S. pneumoniae isolates, susceptible or resistant to vancomycin, methicillin or penicillin, respectively). Interpretation using EUCAST and FDA breakpoints differed among isolates of K. pneumoniae and Enterobacter spp. having tigecycline MICs of 2 to 4 mg/L. In conclusion, tigecycline exhibited potent activity against pathogens recently isolated in a region that experiences high antimicrobial resistance rates. Indications that the available criteria might categorize differently tigecycline susceptibility status in K. pneumoniae and Enterobacter spp. isolates were also detected.
2009
Bloemendaal ALA, Fluit AC, Jansen WTM, Vriens MR, Ferry T, Amorim JM, Pascual A, Stefani S, Papaparaskevas J, Borel Rinkes IHM, et al. Colonization with multiple Staphylococcus aureus strains among patients in European intensive care units. Infect Control Hosp Epidemiol. 2009;30(9):918-20.
Papaevangelou V, Vintila A, Papaparaskevas J, Kanavaki S, Garoufi A, Tsoukatou T, Tsolia M. Infant penile tuberculosis following circumcision. J Infect. 2009;58(1):83-5.Abstract
Primary penile tuberculosis associated with bilateral inguinal lymphadenopathy is described in a previously healthy 10-month old infant, who had been circumcised in Pakistan 4 months earlier. Mycobacterium tuberculosis was detected by acid fast stain, PCR and culture in specimens obtained from the penile ulcer and the excised inguinal lymph nodes.
2008
Papaparaskevas J, Houhoula DP, Siatelis A, Tsakris A. Molecular-beacon-based real-time PCR for detection and quantification of Mycobacterium tuberculosis DNA in clinical samples. J Clin Microbiol. 2008;46(9):3177-8.
Papaparaskevas J, Pantazatou A, Katsandri A, Houhoula DP, Legakis NJ, Tsakris A, Avlamis A. Moxifloxacin resistance is prevalent among Bacteroides and Prevotella species in Greece. J Antimicrob Chemother. 2008;62(1):137-41.Abstract
OBJECTIVES: Moxifloxacin is recommended in the empirical treatment of infections involving Gram-negative anaerobes. However, current European data regarding its activity against anaerobic pathogens are limited. In order to evaluate its potency, we comparatively studied the activity of moxifloxacin against recently isolated Gram-negative anaerobes. METHODS: Four hundred and ninety-five Gram-negative anaerobic clinical isolates (296 Bacteroides fragilis group, 58 non-fragilis Bacteroides spp. and 141 Prevotella spp.) were prospectively recovered in six Greek hospitals. Moxifloxacin MICs were determined in comparison with those of penicillin, piperacillin/tazobactam, cefoxitin, imipenem, metronidazole and clindamycin. RESULTS: Overall moxifloxacin MIC(50) and MIC(90) were 2 and 32 mg/L, respectively. Based on the current CLSI breakpoints (susceptible, < or =2 mg/L; resistant, > or =8 mg/L), almost half of the total isolates (49%) were non-susceptible to moxifloxacin (32% resistant; 17% intermediate). This was more evident among the non-fragilis Bacteroides species, where 47% of the isolates were resistant and 14% intermediate to moxifloxacin. Species variation was noticed, with the highest non-susceptible rates detected among Prevotella oralis (90%), Prevotella bivia (80%), Bacteroides thetaiotaomicron (75%), Bacteroides uniformis (70%) and Bacteroides capillosus (67%) species. Among the 19 (4%) isolates that were metronidazole non-susceptible (MIC > or = 16 mg/L), only 4 (21%) were additionally non-susceptible to moxifloxacin. CONCLUSIONS: High resistance rates to moxifloxacin among Bacteroides and Prevotella spp. were recorded, exceeding those previously reported in Europe and contraindicating its use as monotherapy for infections involving Gram-negative anaerobes without prior microbiological confirmation. For empirical usage, moxifloxacin should be combined with metronidazole in order to cover for these pathogens.
Pittaras TE, Papaparaskevas J, Houhoula DP, Legakis NJ, Frangouli E, Katsambas A, Tsakris A, Papadogeorgakis H. Comparison of penile skin swab with intra-urethral swab and first void urine for polymerase chain reaction-based diagnosis of Chlamydia trachomatis urethritis in male patients. Sex Transm Dis. 2008;35(12):999-1001.
Stathi A, Papaparaskevas J, Zachariadou L, Pangalis A, Legakis NJ, Tseleni-Kotsovili A, Tassios PT. Prevalence of emm types 1 and 12 from invasive Streptococcus pyogenes disease in Greece--results of enhanced surveillance. Clin Microbiol Infect. 2008;14(8):808-12.Abstract
Among a total of 101 isolates from the first systematic multicentre surveillance effort concerning invasive Streptococcus pyogenes disease in Greece, conducted between 2003 and 2005 and covering 38% of the population, emm types 1 and 12 were prevalent, being responsible for 27 and nine cases, respectively. The isolates from the remaining 65 cases were assigned to 26 other emm types. Erythromycin resistance (12 isolates) was primarily mef(A)-mediated, although all emm type 1 strains were susceptible. Tetracycline resistance, due mostly to tet(M), was detected in 26 isolates. Subtyping by pulsed-field gel electrophoresis yielded 50 chromosomal fingerprints, thus discriminating further among ten of the 28 observed emm types.
Katsandri A, Avlamis A, Vasilakopoulou A, Mela V, Kosmidis C, Papaparaskevas J, Petrikkos GL. Risk factors for coexistence of fluoroquinolone resistance and ESBL production among Enterobacteriaceae in a Greek university hospital. J Chemother. 2008;20(4):452-7.Abstract
The purpose of this study was to identify risk factors for fluoroquinolone resistance (QR) among ESBL- producing Enterobacteriaceae causing nosocomial infections. The study was conducted in Laikon General Hospital in Athens, Greece, during the period January 2004 - January 2005. Epidemiological and clinical data were collected from the medical charts of the patients diagnosed with nosocomial infections due to an ESBL-producing Enterobacteriaceae. QR was 60% among the 84 ESBL-producing Enterobacteriaceae isolates. Infection from QR-ESBL bacteria was associated with increased hospital stay (p=0.028); QRESBL bacteria were isolated later during hospitalization than fluoroquinolone susceptible (QS)-ESBL (p=0.089); factors associated with QR were immune-deficiency (p=0.047), previous use of carbapenems (p=0.08) and fluoroquinolones (p=0.067), and admission to the Transplantation Unit (p=0.047). In addition, QR-ESBL bacteria were more likely to be resistant to co-trimoxazole (p<0.001), gentamicin (p=0.054) and tobramycin (p=0.004). Logistic regression analysis indicated that admission to the transplantation unit was an independent risk factor for infection due to a QR-ESBL isolate. Results of this study question ciprofloxacin's usefulness as a valid alternative to carbapenems in our hospital for the treatment of infections due to ESBL-producing bacteria. In addition strategies for addressing the QR-ESBL situation should focus on limiting fluoroquinolone and carbapenem consumption and emphasize on barrier precautions in patients with longer hospitalization, immunosuppression, or admission to the transplantation unit.
Lamagni TL, Darenberg J, Luca-Harari B, Siljander T, Efstratiou A, Henriques-Normark B, Vuopio-Varkila J, Bouvet A, Creti R, Ekelund K, et al. Epidemiology of severe Streptococcus pyogenes disease in Europe. J Clin Microbiol. 2008;46(7):2359-67.Abstract
The past 2 decades have brought worrying increases in severe Streptococcus pyogenes diseases globally. To investigate and compare the epidemiological patterns of these diseases within Europe, data were collected through a European Union FP-5-funded program (Strep-EURO). Prospective population-based surveillance of severe S. pyogenes infection diagnosed during 2003 and 2004 was undertaken in 11 countries across Europe (Cyprus, the Czech Republic, Denmark, Finland, France, Germany, Greece, Italy, Romania, Sweden, and the United Kingdom) using a standardized case definition. A total of 5,522 cases were identified across the 11 countries during this period. Rates of reported infection varied, reaching 3/100,000 population in the northern European countries. Seasonal patterns of infection showed remarkable congruence between countries. The risk of infection was highest among the elderly, and rates were higher in males than in females in most countries. Skin lesions/wounds were the most common predisposing factor, reported in 25% of cases; 21% had no predisposing factors reported. Skin and soft tissue were the most common foci of infection, with 32% of patients having cellulitis and 8% necrotizing fasciitis. The overall 7-day case fatality rate was 19%; it was 44% among patients who developed streptococcal toxic shock syndrome. The findings from Strep-EURO confirm a high incidence of severe S. pyogenes disease in Europe. Furthermore, these results have identified targets for public health intervention, as well as raising awareness of severe S. pyogenes disease across Europe.
2007
Petrikkos G, Markogiannakis A, Papaparaskevas J, Papapareskevas J, Daikos GL, Stefanakos G, Zissis NP, Avlamis A. Differences in the changes in resistance patterns to third- and fourth-generation cephalosporins and piperacillin/tazobactam among Klebsiella pneumoniae and Escherichia coli clinical isolates following a restriction policy in a Greek tertiary care hospita. Int J Antimicrob Agents. 2007;29(1):34-8.Abstract
The aim of the present study was to investigate whether replacement of broad-spectrum cephalosporins (CEPs) by piperacillin/tazobactam (TZP) as first-line empirical therapy may have an effect on beta-lactam resistance among Klebsiella pneumoniae and Escherichia coli in a tertiary care hospital. Data regarding CEP and TZP consumption and resistance were collected on a bimonthly basis during an open-label 2-year (1 year observational and 1 year interventional) study. Consumption of ceftazidime was reduced by 64.5%. In contrast, consumption of the other third-generation CEPs (cefotaxime and ceftriaxone) remained almost stable, whereas an increase in consumption of TZP by 2.8-fold was observed. A significant decrease in resistance to third-generation cephalosporins among K. pneumoniae isolates was observed, and the incidence of extended-spectrum beta-lactamase-producing isolates was notably reduced. These findings were less evident among E. coli isolates. Despite the significant increase in TZP consumption, the respective resistance rates of both bacterial species examined have remained almost unchanged.
Papaparaskevas J, Pantazatou A, Stefanou I, Mela V, Galatidis N, Avlamis A. Differences in the evolution of imipenem susceptibility among Klebsiella pneumoniae and Escherichia coli isolates during a 6-year period in a tertiary care hospital. Int J Antimicrob Agents. 2007;29(2):197-200.Abstract
The evolution of imipenem disk-diffusion susceptibility results of 2652 strains of Klebsiella pneumoniae and 7596 Escherichia coli isolated during the period 2000-2005 were analysed. Screening for production of metallo-beta-lactamases was performed using the EDTA-synergy method. The percentage rate of K. pneumoniae isolates having a zone diameter < or =25 mm increased from 20% in 2000 to 41% in 2005, whereas the respective rate of isolates having a zone diameter > or =30 mm decreased from 48 to 23%. These changes were more evident during 2000-2002, followed in 2003 by the isolation of the first imipenem-resistant strains. Regarding E. coli, a similar decrease was observed (the rates of isolates having a zone diameter < or =25 mm and > or =30 mm changed from 7% and 68% in 2000, to 32% and 36% in 2005, respectively) following the respective changes of K. pneumoniae. A total of 20 K. pneumoniae strains, but no E. coli, were confirmed as metallo-beta-lactamase producers. In conclusion, a decrease of the imipenem susceptibility prior to the isolation of the first resistant strains in a tertiary care hospital was detected, as well as differences in this decrease between the two species. These findings indicate that monitoring of the evolution of imipenem susceptibility in real-time may help in unveiling forthcoming resistance and in implementing the appropriate diagnostic techniques.
2006
Katsandri A, Avlamis A, Pantazatou A, Houhoula DP, Papaparaskevas J. Dissemination of nim-class genes, encoding nitroimidazole resistance, among different species of Gram-negative anaerobic bacteria isolated in Athens, Greece. J Antimicrob Chemother. 2006;58(3):705-6.
Katsandri A, Papaparaskevas J, Pantazatou A, Petrikkos GL, Thomopoulos G, Houhoula DP, Avlamis A. Two cases of infections due to multidrug-resistant Bacteroides fragilis group strains. J Clin Microbiol. 2006;44(9):3465-7.Abstract
Bacteroides fragilis group strains are still considered susceptible to most antimicrobial agents used for the treatment of infections caused by anaerobic organisms. We describe two cases of infections due to isolates simultaneously resistant to clindamycin, tetracycline, cefoxitin, piperacillin-tazobactam, and imipenem and, in one of the two cases, to metronidazole. Such infections, although still rare, do exist and tend to complicate treatment.
Katsandri A, Avlamis A, Pantazatou A, Petrikkos GL, Legakis NJ, Papaparaskevas J. In vitro activities of tigecycline against recently isolated Gram-negative anaerobic bacteria in Greece, including metronidazole-resistant strains. Diagn Microbiol Infect Dis. 2006;55(3):231-6.Abstract
The in vitro activity of tigecycline was compared with those of benzylpenicillin, piperacillin + tazobactam, cefoxitin, imipenem, metronidazole, clindamycin, and tetracycline against 249 Gram-negative anaerobic bacteria (158 Bacteroides fragilis group, 27 non-fragilis Bacteroides spp., 44 Prevotella spp., and 20 miscellaneous), recently isolated from 8 general hospitals in Athens, Greece. Overall tigecycline MIC(50) and MIC(90) were 0.25 and 2 mg/L, respectively, whereas B. fragilis group MIC(50) and MIC(90) were 0.5 and 4 mg/L, respectively. In total, 93% of the isolates were susceptible to tigecycline (MIC /= 32 mg/L) was detected. In addition, tigecycline exhibited good activity against metronidazole- and tetracycline-resistant isolates (MIC(90), 0.5 and 8 mg/L, respectively). In summary, tigecycline exhibits good in vitro activity against Gram-negative anaerobic bacteria isolated in Greece, as well as stability to the most common occurring resistance mechanisms, attributes that make this parenteral agent an attractive alternative for use against infections involving these microorganisms.
Sipsas NV, Papaparaskevas J, Stefanou I, Kalatzis K, Vlachoyiannopoulos P, Avlamis A. Septic arthritis due to Roseomonas mucosa in a rheumatoid arthritis patient receiving infliximab therapy. Diagn Microbiol Infect Dis. 2006;55(4):343-5.Abstract
We report a case of septic arthritis due to Roseomonas mucosa in a rheumatoid arthritis patient receiving infliximab therapy. This is the first report of septic arthritis due to R. mucosa, and infliximab therapy might be a predisposing factor because this infection was never reported in the pre-anti-tumor necrosis factor alpha therapy period.
2005
Papaparaskevas J, Pantazatou A, Katsandri A, Legakis NJ, Avlamis A. Multicentre survey of the in-vitro activity of seven antimicrobial agents, including ertapenem, against recently isolated Gram-negative anaerobic bacteria in Greece. Clin Microbiol Infect. 2005;11(10):820-4.Abstract
The in-vitro activities of penicillin, ticarcillin-clavulanic acid, cefoxitin, imipenem, ertapenem, metronidazole and clindamycin were evaluated against 138 Gram-negative anaerobic isolates (82 Bacteroides fragilis group, 17 non-fragilis Bacteroides spp., 31 Prevotella spp., four Fusobacterium spp., two Veillonella spp., one Porphyromonas sp. and one Tissierella praeacuta) collected from six general hospitals in Athens, Greece. Overall rates of non-susceptibility (both resistant and intermediately-resistant) to penicillin and ticarcillin-clavulanic acid were 81.8% and 2.3%, respectively. The rates of non-susceptibility to cefoxitin and clindamycin were 30.3% and 31.1%, respectively, and that for metronidazole was 4.3% (four Prevotella spp. isolates, one Porphyromonas sp. isolate and one B. fragilis isolate). Only the single B. fragilis isolate was nim-positive by PCR. Only one B. fragilis isolate was resistant to both carbapenems tested, while six more Bacteroides spp. isolates were imipenem-susceptible and ertapenem-non-susceptible. The MIC range, MIC(50) and MIC(90) values were comparable for imipenem and ertapenem, although ertapenem MIC(90)s were one or two two-fold dilutions higher.
2004
Kalocheretis P, Baimakou E, Zerbala S, Papaparaskevas J, Makriniotou I, Tassios PT, Iatrou C, Kouskouni E, Zerva L. Dissemination of vancomycin-resistant enterococci among haemodialysis patients in Athens, Greece. J Antimicrob Chemother. 2004;54(6):1031-4.Abstract
OBJECTIVES: Vancomycin-resistant enterococci (VRE) may colonize haemodialysis patients, but their epidemiology in this population is not well defined. Within the few last years, VRE strains have emerged and are increasingly isolated in the nosocomial environment in Greece, but colonization of dialysis patients has never been evaluated before. This study sought to determine the epidemiology of VRE colonization within this high-risk population and define the risk factors. MATERIALS AND METHODS: During a 4 month period, rectal swabs or faecal specimens were collected from 334 consecutive outpatients, who were treated at four independent dialysis units located in the same area of Athens and referring patients to the same local hospital. The relatedness of isolates was defined by molecular typing, and demographic and clinical patient data were recorded. RESULTS: Thirteen multiresistant Enterococcus faecium vanA strains were isolated corresponding to a colonization frequency of 3.9%. They were separated into seven clusters: type A (two strains), type B (six strains) and types C to G (one strain each). Type B strains originated from three units, while a single unit demonstrated four type B and two type A strains. Univariate statistical analysis revealed that prior hospitalization (P=0.001), prior administration of antimicrobials (P=0.026) and male gender (P=0.019) were associated with VRE colonization. CONCLUSIONS: In Greece, haemodialysis patients are colonized with VRE at a low frequency. The predominance of one clone and its isolation from several units strongly indicate interfacility transmission of strains, most probably within a health care environment shared by all patients.
Papaparaskevas J, Houhoula DP, Papadimitriou M, Saroglou G, Legakis NJ, Zerva L. Ruling out Bacillus anthracis. Emerg Infect Dis. 2004;10(4):732-5.Abstract
Optimization of methods for ruling out Bacillus anthracis leads to increased yields, faster turnaround times, and a lighter workload. We used 72 environmental non-B. anthracis bacilli to validate methods for ruling out B. anthracis. Most effective were the use of horse blood agar, motility testing after isolates had a 2-h incubation in trypticase soy broth, and screening isolates with a B. anthracis-selective agar.
2003
Fotopoulou N, Tassios PT, Beste DV, Ioannidou S, Efstratiou A, Lawrence ER, Papaparaskevas J, George RC, Legakis NJ. A common clone of erythromycin-resistant Streptococcus pneumoniae in Greece and the UK. Clin Microbiol Infect. 2003;9(9):924-9.Abstract
OBJECTIVE: To investigate the possible genetic relationship among erythromycin-resistant Streptococcus pneumoniae strains isolated in Greece and the UK. METHODS: During 1995-97, 140 S. pneumoniae strains were isolated from clinical specimens submitted to the microbiology departments of the two main children's hospital in Athens. All erythromycin-resistant strains were further studied with respect to the presence of genes encoding for the two major mechanisms of macrolide resistance, their serotypes, and pulsed-field gel electrophoresis (PFGE) types, in comparison to a previously characterized UK erythromycin-resistant clone. RESULTS: Eleven of the 140 isolates (7.9%) were resistant to erythromycin; nine of these were susceptible to penicillin. Serotyping allocated seven, three and one isolates to serotypes 14, 19F and serogroup 6, respectively. The mefA gene was detected in seven isolates (five serotype 14 and two serotype 19F), ermB in two (one serotype 19F and the serogroup 6 isolate), whilst in the remaining two isolates no resistance gene could be detected by polymerase chain reaction (PCR). Pulsed-field gel electrophoresis of genomic DNA showed that five Greek serotype 14 isolates belonged to the same chromosomal type as the serotype 14 erythromycin-resistant UK clone. CONCLUSIONS: The present study showed that erythromycin resistance among the S. pneumoniae isolates was mostly owing to the efflux mechanism and suggested a possible clonal spread of serotype 14 erythromycin-resistant S. pneumoniae strains between Greece and the UK.
Pantazatou A, Papaparaskevas J, Stefanou I, Papanicolas J, Demertzi E, Avlamis A. Changes in the epidemiology of methicillin-resistant Staphylococcus aureus in a Greek tertiary care hospital, over an 8-year-period. Int J Antimicrob Agents. 2003;21(6):542-6.Abstract
A total of 1019 non-replicate, consecutively isolated methicillin-resistant Staphylococcus aureus (MRSA) strains were collected from in-patients of a tertiary care general hospital in Athens, Greece, during the period 1994-2001. The susceptibility, resistance phenotypes and the dissemination of these isolates among hospital wards were studied. Total MRSA and gentamicin-resistant MRSA, as a proportion of the S. aureus isolates, increased from 33 and 9% in 1994 to 50.1 and 33.3% in 2001, respectively. Three main multi-resistant phenotypes predominated, representing 50.9% of the total MRSA isolates in 2001. MRSA strains susceptible to all antibiotics tested decreased to 1.9% in 1997 and again increased to 13.5% in 2001. A gradual decrease in the susceptibility of vancomycin during the 8-year-period was detected, but no vancomycin resistant S. aureus strains were isolated.
Ioannidou S, Papaparaskevas J, Tassios PT, Foustoukou M, Legakis NJ, Vatopoulos AC. Prevalence and characterization of the mechanisms of macrolide, lincosamide and streptogramin resistance in viridans group streptococci. Int J Antimicrob Agents. 2003;22(6):626-9.Abstract
The presence of erm genes conferring constitutive and inducible resistance, as well as that of the mefA gene conferring only constitutive resistance, was investigated using PCR in 70 erythromycin resistant (MIC>or=1 mg/l) strains of viridans group streptococci (VGS) (18 Streptococcus mitis biotype 1, 16 S. mitis biotype 2, 15 S. oralis, 12 S. salivarius and nine S. sanguis) isolated from the oropharynx of healthy Greek children. All of the 56 isolates belonging to resistance phenotype M harbored the mefA gene. All of the 14 isolates constitutively resistant to macrolides and lincosamides (phenotype CR) harbored the ermB gene. Co-presence of both genes was not observed, whereas class A erm gene (previously known as ermTR) was not detected. Our results are consistent with a possible role of VGS as a reservoir of resistance genes now prevalent in pathogenic species of streptococci.
Zachariadou L, Papaparaskevas J, Paraskakis I, Efstratiou A, Pangalis A, Legakis NJ, Tassios PT. Predominance of two M-types among erythromycin-resistant group A Streptococci from Greek children. Clin Microbiol Infect. 2003;9(4):310-4.Abstract
In order to investigate the potential relationship between erythromycin resistance and specific M-serotypes among clinical isolates of Streptococcus pyogenes from children in Greece, we randomly selected a total of 49 erythromycin-resistant (EryR) and 21 erythromycin-susceptible (EryS) isolates from the 1158 S. pyogenes isolates from the two main children's hospitals of Athens during the period October 1997 to October 1998. The isolates were further characterized by M-serotyping, examined for their susceptibility to penicillin, vancomycin and clindamycin, and categorized into resistance phenotypes. A total of 248 (21%) S. pyogenes isolates in the two main children's hospitals of Athens during the study period were resistant to erythromycin. All 49 EryR and 21 EryS isolates were susceptible to penicillin and vancomycin. With respect to erythromycin and clindamycin resistance, phenotypes M and IR MLSB dominated, with 30 and 17 isolates, respectively, two isolates belonged to the CR MLSB phenotype. Among the erythromycin resistant isolates, two M serotypes were dominant: M22 (30%) and M84 (41%). More specifically, M22 and M84 were most prevalent in resistance phenotypes IR MLSB (65%) and M (63%), respectively. In the susceptible group, no isolate belonged to these two M-serotypes, nor was a predominant serotype found. In contrast to susceptible isolates, two distinct M-serotypes were highly represented among EryR S. pyogenes isolates and predominantly associated with two distinct phenotypes.
2002
Papaparaskevas J, Tassios PT, Kalapothaki V, Avlami A, Legakis NJ, Vatopoulos AC. Epidemiology of multiresistant Enterococcus avium isolates in a Greek tertiary care hospital. Int J Antimicrob Agents. 2002;20(6):432-7.Abstract
A retrospective survey of the isolation rate of Enterococcus avium during the period March 1994-February 2000 conducted in Laikon General Hospital using the WHONET software, revealed a peak in the isolation rates of this species during March 1995-February 1996. The ten strains isolated during this time were studied further. No glycopeptide resistance was detected but resistance to ampicillin, ciprofloxacin, erythromycin, gentamicin (high-level) and streptomycin (high-level) was present in nine, ten, nine, three and seven of the isolates, respectively. The genes aac(6')-Ie+aph(2")-Ia and ant(6)-I, encoding for high-level gentamicin and streptomycin resistance, respectively, were detected only in the isolates with the corresponding phenotypes. Beta-lactamase production and haemolysis were not detected. There was evidence of ward-, floor- and building-specific distribution among the different aminoglycoside resistance phenotypes. DNA fingerprinting by PFGE grouped six of the ten isolates in a single cluster with 83% similarity, even though they expressed various resistance phenotypes. These results suggest dissemination of resistance genes among both genetically related and unrelated strains.
2000
Kouppari G, Papadaki H, Arida C, Sakellariou J, Legakis NJ, Papaparaskevas J. First report of ampicillin and glycopeptide resistant Enterococcus faecium VanA bacteraemia in Greece. Int J Antimicrob Agents. 2000;16(3):254-6.
Papaparaskevas J, Vatopoulos A, Tassios PT, Avlami A, Legakis NJ, Kalapothaki V. Diversity among high-level aminoglycoside-resistant enterococci. J Antimicrob Chemother. 2000;45(3):277-83.Abstract
A total of 55 Enterococcus faecalis and 21 Enterococcus faecium non-replicate isolates were obtained from routine clinical specimens, during a 1 year period, in a tertiary care hospital in Athens, Greece. The most common isolation site was the urinary tract (44% of E. faecalis and 33% of E. faecium isolates). No vancomycin resistance was detected. Ampicillin-resistant isolates did not produce beta-lactamase. High-level gentamicin resistance was detected in 22% and 0% of E. faecalis and E. faecium isolates, respectively. The corresponding figures for high-level streptomycin resistance were 40% and 33%. The aminoglycoside-modifying enzyme gene aac(6')+aph(2") was detected by PCR in 10 of 12 high-level gentamicin-resistant E. faecalis isolates, and the ant(6)-I gene in all high-level streptomycin-resistant isolates of both species. DNA fingerprinting by PFGE grouped 31 of 55 E. faecalis isolates into 10 clusters, and 10 of 21 E. faecium isolates into two clusters, containing two to seven isolates each. Two E. faecalis PFGE types, comprising isolates expressing high-level aminoglycoside resistance, and not observed among non-high-level aminoglycoside-resistant strains, were disseminated in building A of the hospital. In contrast, high-level aminoglycoside resistance seemed to have been acquired nosocomially by a number of genotypically different E. faecium types. Molecular typing was therefore instrumental in understanding the differences in the mode of spread and acquisition of high-level aminoglycoside resistance among these two different enterococcal species.
Archimandritis A, Tzivras M, Sougioultzis S, Papaparaskevas I, Apostolopoulos P, Avlami A, Davaris PS. Rapid urease test is less sensitive than histology in diagnosing Helicobacter pylori infection in patients with non-variceal upper gastrointestinal bleeding. J Gastroenterol Hepatol. 2000;15(4):369-73.Abstract
BACKGROUND AND AIMS: The validity of the rapid urease (CLO) test to diagnose Helicobacter pylori infection in patients with bleeding ulcers has been questioned. The aim of this paper is to evaluate the validity of the CLO test in comparison with histology in diagnosing H. pylori infection in patients with acute upper gastrointestinal bleeding (UGB), irrespective of non-steroidal anti-inflammatory drug (NSAID) use. METHODS: Upper gastrointestinal endoscopy was performed within 24 h of admission for all patients with UGB admitted to the Department of Pathophysiology, Medical School, Athens, for a period of 12 months. Patients with variceal bleeding, previous gastric operation, recent treatment with proton pump inhibitors (< 2 months) and those with a history of H. pylori eradication therapy were excluded from the study. At least four biopsies (two from the antrum and two from the body) were obtained for the CLO test and histology (modified Giemsa). RESULTS: Seventy-two consecutive patients (aged 18-90 years, 51 men, 21 women) were included. Forty-six patients (64%) used NSAID. Thirty-two patients (44%) were found to be positive for H. pylori infection by the CLO test, while 44 patients (61%) were found to be positive on histology (P<0.045, 95% CI, 0.004-0.331). The sensitivity and specificity of the CLO test were 68 and 93% respectively; positive and negative predictive values were 94 and 65%, respectively. The age of the patient and visible blood in the stomach did not influence results of either the CLO or histology. CONCLUSIONS: The CLO test, performed within 24 h of hospital admission in patients with UGB, irrespective of NSAID use, is unreliable for the detection of H. pylori infection. The age of the patient and the presence of blood in the stomach do not seem to influence these results.
1997
Avlami A, Schina M, Tzivra M, Stefanou I, Papaparaskevas N, Sakellaropoulos N. Postanginal sepsis syndrome with metastatic lung abscess in a young man. Anaerobe. 1997;3(2-3):149-51.Abstract
A postanginal Sepsis Syndrome with metastatic lung abscess caused by Fusobacterium necrophorumin a 25-year-old previously healthy man is described. The incomplete and ineffective antibiotic treatment at onset of angina ended progressively in septicaemia and metastatic infections in a 3-week time period. The early parenteral use of Metronidazole based only on the clinical picture, the Gram stain findings and the strict anaerobic feature of the blood isolate in parallel with the long-term antibiotic treatment were possibly the main reasons for the good outcome of this serious infection.