Evangelia Lebessi

The impact of the heptavalent pneumococcal conjugate vaccine on the epidemiology of acute otitis media complicated by otorrhea.

Background: The heptavalent pneumococcal conjugate vaccine (PCV7) has a considerable effect on the epidemiology of pneumococcal disease. The aim of this observational hospital-based study was to examine the effect of the PCV7 (introduced in our settings in 2004) on the epidemiology of spontaneously draining acute otitis media. Methods: Results of all middle ear fluid cultures (n = 3446) obtained from children with acute otitis media complicated with otorrhea before the introduction of immunization (between 2000 and 2003) were compared with those (n = 2134) obtained during a similar post-PCV7 period (between 2005 and 2008). Results of cultures obtained between 2006 and 2008 were examined prospectively, whereas those obtained in previous years were retrospectively reviewed. Results: Following PCV7 immunization, the rates of otorrhea visits per 10,000 emergency department visits decreased by 38% from 133 to 83 (95% confidence interval of the difference, 42–53; P < 0.001), mainly as a result of the decrease in the incidence of pneumococcal disease (48% decrease—25 vs. 13 per 10,000 emergency department visits; P < 0.001). Otorrhea due to Haemophilus influenzae decreased by 20% (20–16 per 10,000 visits; P < 0.001). Serotype 19A accounted for 1 of 47 (2%) pneumococcal strains in 2006, for 5 of 34 (15%) in 2007, and for 13 of 53 (25%) in 2008 (P for trend: 0.001). In the postvaccine years, penicillin-resistant pneumococcal strains (minimum inhibitory concentration ≥2 &mgr;g/mL) increased from 4% to 13% (P < 0.001). However, the proportion of pneumococci resistant to macrolides decreased (44% vs. 35%; P = 0.01). Conclusions: After the introduction of immunization, otorrhea incidents decreased considerably, mainly because of the decrease in pneumococcal disease. H. influenzae is now the predominant organism. Serotype 19A has increased significantly and is the most common nonvaccine pneumococcal serotype. Penicillin resistance has increased in recent years.

Nosocomial Outbreak of Extended-Spectrum β-Lactamase SHV-5-Producing Isolates of Pseudomonas aeruginosa in Athens, Greece

ABSTRACT Seven nonrepetitive Pseudomonas aeruginosa isolates producing the clavulanic acid-inhibited extended-spectrum β-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 blaSHV-5 gene was chromosomally located. This study underlined that this gene, which is widespread in Enterobacteriaceae in Greece, may disseminate also in P. aeruginosa.

Clinical and molecular epidemiology of community-acquired, methicillin-resistant Staphylococcus aureus infections in children in central Greece.

Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections in children have increased considerably in our area. In this study, we prospectively examined the epidemiological, clinical and molecular profile of CA-MRSA infections in children in central Greece. A total of 198 staphylococcal strains were isolated from patients with community-acquired infections over a 28-month period and 88 (44%) were found to be methicillin-resistant. Most patients with CA-MRSA had skin and soft-tissue infections (73%). Hospitalisation and surgery were more commonly required for patients with MRSA strains (p = 0.001 and p < 0.001, respectively). The presence of Panton-Valentine leukocidin (PVL) genes was identified in 28/41 (68%) CA-MRSA strains. All PVL(+) strains were found to carry a staphylococcal chromosomal cassette (SCC) mec element type IV and belonged to a single electrophoretic type similar to the European multi-locus sequence type 80 (ST80). The recent increase in CA-MRSA infections in children in our area is largely associated with the spread of the ST80 clone and their clinical characteristics are similar to those described in other parts of the world where different MRSA clones predominate.

Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae in a Neonatal Intensive Care Unit in the High-Prevalence Area of Athens, Greece

ABSTRACT Extended-spectrum β-lactamase-producing Klebsiellapneumoniae (EPKP) strains are frequently implicated in outbreaks in neonatal intensive care units (NICUs). During the period from 1997 to 1998, 21 infections and 23 colonizations with EPKP were recorded in the NICU of a childrens hospital in Athens, Greece. Seventeen of the infected and 12 of the colonized neonates had been referred from other hospitals. The remaining infections and colonizations occurred during the current hospitalization. Pulsed-field gel electrophoresis typing showed that the latter cases were due to an outbreak strain that persisted in the unit, while the repeated introduction of EPKP carriers was mostly due to clonal outbreaks in two maternity hospitals.

Polyphasic Identification and Susceptibility to Seven Antifungals of 102 Aspergillus Isolates Recovered from Immunocompromised Hosts in Greece

ABSTRACT 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.

Microbiology of acute mastoiditis and complicated or refractory acute otitis media among hospitalized children in the postvaccination era.

In the post–heptavalent pneumococcal conjugate vaccine era, Streptococcus pneumoniae remains the leading cause of acute mastoiditis and other complicated or refractory acute otitis media among hospitalized children in our settings. Serotype 19A is predominant, invasive and multidrug resistant causing more than half of all mastoiditis cases, two-thirds of cases with subperiosteal abscess and all those requiring mastoidectomy. Continuous surveillance is required.

Scedosporium apiospermum skeletal infection in an immunocompetent child.

Abstract This is a case of Scedosporium apiospermum skeletal infection in a 10-year-old immunocompetent girl whose chief complaint was left knee swelling and pain. The child had a history of a bicycle accident two months before with a resultant deep penetrating trauma. Systematic administration of broad-spectrum antibiotics for 10 days was used, with no clinical improvement. Magnetic Resonance Imaging and arthrotomy of the affected joint revealed findings suggestive of osteomyelitis. Empirical intravenous antimicrobial therapy was instituted for a total of two months but one month after completion of antibacterial therapy the child returned to the hospital because of persistent knee swelling and pain. Following a new arthrotomy, Scedosporium apiospermum was isolated. The patient was cured with intravenous administration of voriconazole without any side effects and has no evidence of relapse after four years of follow-up.

Associations Between Viral and Bacterial Potential Pathogens in the Nasopharynx of Children With and Without Respiratory Symptoms.

Background: Nasopharyngeal (NP) bacterial colonization is necessary for subsequent respiratory and/or invasive infection. Our study aimed at comparing NP bacterial colonization rates between children with and without symptoms of an acute viral respiratory tract infection and examining associations between identified microorganisms. Methods: Children 3 months to 6 years of age with and without an acute viral respiratory tract infection were recruited, and a questionnaire was filled. NP samples were examined for Streptococcus pneumoniae (SP), Haemophilus influenzae (HI), Moraxella catarrhalis (MC), Staphylococcus aureus and Streptococcus pyogenes by culture. Viruses were detected with polymerase chain reaction. Results: Median age of the 386 recruited children was 23.4 months, and 127 had no respiratory symptoms. More asymptomatic subjects were found negative for all bacteria tested (P < 0.01). SP (P < 0.01), MC (P = 0.001) and mixed bacterial colonization patterns were more frequent among symptomatic children (P < 0.05). Colonization of symptomatic, virus-positive children with MC was higher than in asymptomatic and/or virus-negative children (P = 0.005). The highest HI and MC colonization rates were recorded in association with influenza virus. A strongly negative association between SP and S. aureus, a higher rate of HI detection among SP colonized children and an increased likelihood of MC detection in the presence of HI were observed. HI colonization was more likely in the presence of respiratory syncytial virus and MC colonization was associated with rhinovirus detection. Conclusions: Viruses are associated with different NP bacterial colonization patterns. Observed pathogens’ associations may play a role in disease, and continuous surveillance is required to follow possible effects of interventions such as vaccines.

Resistance pattern of Streptococcus pneumoniae in children during a four-year period in greece

Abstract The resistance pattern of 432 Streptococcuspneumoniae strains isolated from children with various infections over a 4-year period (1992–1995) was determined. The rates of resistance to penicillin, chloramphenicol, tetracycline, trimethoprim-sulfamethoxazole, erythromycin, clindamycin, cefotaxime, and vancomycin were 10%, 2.8%, 4.6%, 4.9%, 4.4%, 2.5%, 0.9%, and 0%, respectively. All strains not susceptible to penicillin were intermediately susceptible to penicillin-(MIC >0.06–≤1 μg/ml). Isolates not susceptible to penicillin were encountered significantly more often in children with localized infections than in those with invasive disease; these isolates displayed significantly lower susceptibility to non-β-lactam agents as compared with their penicillin-susceptible counterparts.

Cefditoren: Comparative efficacy with other antimicrobials and risk factors for resistance in clinical isolates causing UTIs in outpatients

BackgroundTo investigate a possible role of Cefditoren, a recently marketed in Greece third-generation oral cephalosporin in urinary infections of outpatients.MethodsDuring a multicenter survey of Enterobacteriaceae causing UTIs in outpatients during 2005–2007, Cefditoren MICs were determined by agar dilution method in a randomly selected sample of uropathogens. Susceptibility against 18 other oral/parenteral antimicrobials was determined according to Clinical and Laboratory Standards Institute methodology.ResultsA total of 563 isolates (330 Escherichia coli, 142 Proteus mirabilis and 91 Klebsiella spp) was studied; MIC50/MIC90 of Cefditoren was 0.25/0.5 mg/L respectively, with 97.1% of the isolates being inhibited at 1 mg/L. All 12 strains producing ESBLs or AmpC enzymes were resistant to cefditoren. Susceptibility rates (%) for amoxicillin/clavulanic acid, cefuroxime axetil, cefotaxime, ciprofloxacin, trimethoprim/sulfamethoxazole and fosfomycin were 93.1- 94.1- 96.8-93.1-71.9 and 92.8% respectively. Cefditoren MIC was significantly higher in nalidixic/ciprofloxacin non-susceptible strains; resistance to cefditoren was not associated with resistance to mecillinam, fosfomycin nitrofurantoin and aminoglycosides. Multivariate analysis demonstrated history of urinary infection in the last two weeks or three months as risk factors for cefditoren resistance.ConclusionsCefditoren exhibited enhanced in vitro activity against the most common uropathogens in the outpatient setting, representing an alternative oral treatment option in patients with risk factors for resistance to first-line antibiotics.