Polyphasic identification and susceptibility to seven antifungals of 102 Aspergillus isolates recovered from immunocompromised hosts in Greece.

In this study, the first such study in Greece, we used polyphasic identification combined with antifungal susceptibility study to analyze Aspergillus clinical isolates comprising 102 common and rare members of sections Fumigati, Flavi, Terrei, Nidulantes, Nigri, Circumdati, Versicolores, and Usti. High amphotericin B MICs (>2 µg/ml) were found for 17.6% of strains. Itraconazole, posaconazole, and voriconazole MICs of >4 µg/ml were shown in 1%, 5%, and 0% of the isolates, respectively. Anidulafungin, micafungin, and caspofungin minimum effective concentrations (MECs) of ≥2 µg/ml were correspondingly recorded for 4%, 9%, and 33%, respectively, of the strains.

Bacillus cereus meningitis in a term neonate.

A case of Bacillus cereus meningitis in a term neonate without identifiable risk factors or source of the organism is presented. Prompt identification of the organism and treatment resulted in a favourable outcome.

Presumptive varicella vaccination is warranted in Greek adolescents lacking a history of disease or household exposure.

Current practice favors serotesting adolescents with a negative history of chickenpox rather than offering presumptive vaccination. Recent epidemiologic data from Greece indicate that a high proportion of adolescents (21.5%) are susceptible to chickenpox. We assessed the reliability of negative varicella history in relation to type of exposure in 311 children and 283 adolescents. In children with social or unknown exposure to varicella, a negative history had a high negative predictive value (NPV = 73.5), supporting the clinical practice of presumptive vaccination. Conversely, children with a negative history and household exposure had a low NPV (13.8), suggesting that pre-vaccination serologic testing is warranted. In conclusion, based on our local epidemiologic data, presumptive varicella vaccination should be offered to all adolescents with the exception of the subgroup of adolescents with household exposure.

Phenotypic assessment of Neisseria meningitidis isolates obtained from patients with invasive meningococcal disease in Greece, 1993-2003: implications for serogroup B vaccines based on PorA serosubtype antigens.

Serogroup B is the major isolate from patients with invasive meningococcal disease (IMD) in Greece. This study used the whole cell enzyme-linked immuosorbent assay (ELISA) with monoclonal antibodies to screen Neisseria meningitidis isolates obtained from patients with IMD between 1993 and 2003 to determine if serosubtypes included in the hexavalent Por A OMP vaccines being tested in northern Europe were prevalent in Greece. During this period there were significant changes in the proportions of serogroups B and C isolated from patients. Serogroup C was predominant in 1996-1997 but fell sharply with corresponding increases in serogroup B. Of the 591 isolates sent to the National Meningitis Reference Laboratory in Athens during this period, 325 (55%) were serogroup B. Among those tested for serosubtype, porA proteins used for the vaccine being tested in Britain were detected on 85/284 (30%) strains and for the vaccine being tested in the Netherlands 175/284 (62%). P1.14 (58/284, 20%) the predominant serosubtype among the Greek isolates, is not present in either vaccine formulation; 23/284 (8%) strains did not react with any of the monoclonal antibodies. Our results indicate that introduction of the vaccines currently being evaluated in northern Europe would not be warranted in the Greek population.

Nosocomial outbreak of extended-spectrum beta-lactamase SHV-5-producing isolates of Pseudomonas aeruginosa in Athens, Greece.

Seven nonrepetitive Pseudomonas aeruginosa isolates producing the clavulanic acid-inhibited extended-spectrum beta-lactamase SHV-5 were isolated in the same hospital in Athens, Greece, from 1998 to 2002. All isolates except one were clonally related, and the bla(SHV-5) gene was chromosomally located. This study underlined that this gene, which is widespread in Enterobacteriaceae in Greece, may disseminate also in P. aeruginosa.

Prevalence and characterization of the mechanisms of macrolide, lincosamide and streptogramin resistance in viridans group streptococci.

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.

Evaluation of non-culture diagnosis of invasive meningococcal disease by polymerase chain reaction (PCR).

Antibiotic treatment prior to transport or admission to hospital has reduced the proportion of cases of invasive meningococcal disease (IMD) from which Neisseria meningitidis can be isolated by standard microbiological techniques. Identification of meningococci by polymerase chain reaction (PCR) was assessed in relation to microbiological diagnosis for cases over a 4-year period between 1998 and 2001. A screening assay for the IS1106 gene was used to detect meningococcal DNA and five additional assays for siaD and orf-2 genes were performed to determine the serogroup. PCR results were compared with results of bacteriological culture, other laboratory test results and clinical data. The sensitivity of the PCR assay for culture-confirmed cases was 98.5%. The specificity of the assay was 96% based on test results for patients from whom other bacteria were isolated, children with viral meningitis and afebrile negative controls. The siaD B/C/W-135 and Y as well as the orf-2 gene for serogroup A PCR assays were able to determine the serogroup for 75.2% of cases that were positive by PCR screening assay. When isolates from patients with IMD were tested by both agglutination and PCR, the results agreed in all cases. PCR is a useful tool for diagnosis of IMD when Gram stain and culture tests are negative due to antibiotic treatment prior to collection of samples for microbiological analyses.

Genetic relatedness of resistant and multiresistant Streptococcus pneumoniae strains, recovered in the Athens area, to international clones.

The prevalence of resistance to antibiotics was examined among 318 Streptococcus pneumoniae strains isolated during 1998 and 1999 in a children's hospital in Athens. The rate of resistance to penicillin was 25.8% (intermediate 22%, resistant 3.8%); 42.5% of the strains were resistant to > or = 1 antibiotic and 20% were multidrug resistant. Resistance to penicillin was lowest in invasive strains (8.3%) and highest in ear isolates (31%). A review of the same microbiology laboratory's records revealed that there has been a gradual increase in penicillin resistance since 1988-1989, when it was 5%. Capsular types were determined for 77 strains resistant to > or = 1 antibiotic, and 69 (90%) of them belonged to the following five serotypes: 19F, 14, 9V, 23F, and 6B. Seventy-five strains were analyzed by pulsed-field gel electrophoresis (PFGE) and 59/75 (79%) shared five electrophoretic types. The largest cluster consisted of 19 serotype 19F strains, of which 18 were nonsusceptible to penicillin and most were multidrug resistant and shared a common and distinct electrophoretic pattern not resembling any known clone. A group of 17 strains that were nonsusceptible to penicillin belonged to serotypes 9V (10), 14 (6), and 19F (1) and shared a common PFGE type similar to the international clone Spain9V-3. Seven serotype 23F strains, of which five were multidrug resistant, belonged to the international clone Spain23F-1. Among the strains susceptible to penicillin but resistant to non-beta-lactam antibiotics, the largest cluster consisted of 13 isolates resistant to erythromycin that belonged to serotype 14 and shared an electrophoretic pattern characteristic of the clone England14-9. Finally, three serotype 6B strains were penicillin susceptible and multidrug resistant and had features similar to the Mediterranean 6B clone. The introduction and spread of several antibiotic-resistant international clones accounts at least in part for the increase in pneumococcal resistance observed in recent years in the Athens metropolitan area.