Epidemiology of bloodstream infections in children with sickle cell disease.

The incidence of invasive Streptococcus pneumoniae and Haemophilus influenzae type b infections in the sickle cell disease population has declined. In this report, we determine the predominant organisms responsible for bloodstream infections in a pediatric sickle cell disease population during the postheptavalent conjugate vaccine era. Central venous access device associated infections are a new burden to efforts aimed at preventing bloodstream infections in this population.

Medical treatment failure and complete left pneumonectomy after Legionella pneumophila pneumonia in a bone marrow transplant recipient.

Legionnaire disease (LD) is infrequently considered in the differential diagnoses for hospital- and community-acquired pneumonia in pediatrics. We report a case of Legionnaire disease in a 19-year-old male with aplastic anemia after bone marrow transplant, who was being treated in a children's hospital. Severe, refractory pulmonary disease necessitated pneumonectomy to control the infection.

Clostridium difficile testing algorithms using glutamate dehydrogenase antigen and C. difficile toxin enzyme immunoassays with C. difficile nucleic acid amplification testing increase diagnostic yield in a tertiary pediatric population.

We evaluated the performance of the rapid C. diff Quik Chek Complete's glutamate dehydrogenase antigen (GDH) and toxin A/B (CDT) tests in two algorithmic approaches for a tertiary pediatric population: algorithm 1 entailed initial testing with GDH/CDT followed by loop-mediated isothermal amplification (LAMP), and algorithm 2 entailed GDH/CDT followed by cytotoxicity neutralization assay (CCNA) for adjudication of discrepant GDH-positive/CDT-negative results. A true positive (TP) was defined as positivity by CCNA or positivity by LAMP plus another test (GDH, CDT, or the Premier C. difficile toxin A and B enzyme immunoassay [P-EIA]). A total of 141 specimens from 141 patients yielded 27 TPs and 19% prevalence. Sensitivity, specificity, positive predictive value, and negative predictive value were 56%, 100%, 100%, and 90% for P-EIA and 81%, 100%, 100%, and 96% for both algorithm 1 and algorithm 2. In summary, GDH-based algorithms detected C. difficile infections with superior sensitivity compared to P-EIA. The algorithms allowed immediate reporting of half of all TPs, but LAMP or CCNA was required to confirm the presence or absence of toxigenic C. difficile in GDH-positive/CDT-negative specimens.

Pneumococcal bacteremia in a vaccinated pediatric sickle cell disease population.

The incidence of pneumococcal disease in sickle cell disease declined significantly with penicillin prophylaxis as well as with the pneumococcal polysaccharide and heptavalent conjugate vaccines. In this report, we describe our experience with pneumococcal bacteremia in pediatric patients with sickle cell disease in the post-heptavalent pneumococcal conjugate vaccine era. Despite established prophylactic strategies, pneumococcal bacteremia continues to occur in patients with sickle cell disease.

Declining incidence of candidemia in a tertiary inpatient pediatric population.

We examined the incidence of candidemia, Candida species distribution, and antifungal susceptibility patterns in a pediatric institution. We identified 301 episodes of candidemia from 2001 to 2010 inclusive. Annual incidence decreased from 0.68 to 0.12 cases/1,000 patient days between 2004 and 2010. Candida albicans was the most common species, followed by C. parapsilosis. All isolates tested were susceptible to amphotericin B and caspofungin, but 11% were resistant or dose-dependently susceptible to fluconazole.

Identification of sexual networks through molecular typing of quinolone-resistant Neisseria gonorrhoeae in Ontario, Canada.

Neisseria gonorrhoeae multi-antigen sequence typing technique demonstrated multiple sexual transmission networks in Ontario, Canada. Isolates with novel sequences had higher odds of originating in Toronto but had no association with heightened population-level quinolone exposure. Neisseria gonorrhoeae multi-antigen sequence typing technique can be a useful tool for investigation of multidrug-resistant N. gonorrhoeae emergence in North America.

Incidence and treatment outcomes of pharyngeal Neisseria gonorrhoeae and Chlamydia trachomatis infections in men who have sex with men: a 13-year retrospective cohort study.

BACKGROUND: This study investigated the incidence and treatment outcomes of pharyngeal Neisseria gonorrhoeae and Chlamydia trachomatis cases at a Canadian clinic that mainly serves men who have sex with men. METHODS: All patients with pharyngeal N. gonorrhoeae and C. trachomatis infections detected from 1 January 1995 through 31 December 2007 were identified. Original and test-of-cure N. gonorrhoeae culture isolates were compared using antibiotic susceptibility testing and N. gonorrhoeae multiantigen sequence typing. RESULTS: One hundred seventy-eight cases of pharyngeal N. gonorrhoeae infection and 97 cases of pharyngeal C. trachomatis infection were identified, primarily by culture methods. The mean incidence was 1.62 and 0.81 cases per 1000 visits per year for N. gonorrhoeae and C. trachomatis infection, respectively. Poisson regression modeling demonstrated a statistically significant surge of pharyngeal N. gonorrhoeae cases in 2007 after controlling for seasonal and long-term oscillation and long-term linear trends. Among patients with pharyngeal N. gonorrhoeae and C. trachomatis infection, 60.2% and 84.3%, respectively, would have been missed by relying on urine and urethral testing. Nine percent of patients with pharyngeal N. gonorrhoeae and 4.3% of patients with pharyngeal C. trachomatis infection who underwent test-of-cure procedures had at least 1 positive result. Antibiograms were not different in 8 of 10 pretreatment and posttreatment N. gonorrhoeae isolate pairs. N. gonorrhoeae multiantigen sequence typing results were identical in 2 of these cases. Public health records documented abstinence in both individuals. CONCLUSIONS: Nine percent of cases with pharyngeal N. gonorrhoeae and 4.3% of cases with pharyngeal C. trachomatis infection that underwent tests of cure had positive results. Available typing results suggest antibiotic treatment failure rather than reinfection. Specific antibiotic treatment regimens for pharyngeal N. gonorrhoeae and C. trachomatis infections need to be developed and formally evaluated.

Toxocariasis mimicking liver, lung, and spinal cord metastases from retinoblastoma.

A boy with bilateral retinoblastoma underwent metastatic surveillance for increased risk of systemic and central nervous system metastasis because of the extensive choroid and optic nerve invasion in his enucleated eye. Two years after finishing chemotherapy, surveillance MRI showed multiple new liver, lung and spinal cord lesions. High Toxocara antibody titers, eosinophilia, and elevated IgE levels supported a diagnosis of toxocariasis, rather than retinoblastoma metastasis. This is the first report of early, asymptomatic spinal cord toxocariasis diagnosed incidentally through metastatic surveillance.

Prevalence of and risk factors for quinolone-resistant Neisseria gonorrhoeae infection in Ontario.

BACKGROUND: Quinolone-resistant Neisseria gonorrhoeae has swiftly emerged in Canada. We sought to determine its prevalence in the province of Ontario and to investigate risk factors for quinolone-resistant N. gonorrhoeae infection in a Canadian setting. METHODS: We used records from the Public Health Laboratory of the Ontario Agency for Health Protection and Promotion in Toronto, Ontario, and the National Microbiology Laboratory in Winnipeg, Manitoba, to generate epidemic curves for N. gonorrhoeae infection. We extracted limited demographic data from 2006 quinolone-resistant N. gonorrhoeae isolates and from a random sample of quinolone-susceptible isolates. We also extracted minimum inhibitory concentrations for commonly tested antibiotics. RESULTS: Between 2002 and 2006, the number of N. gonorrhoeae infections detected by culture decreased by 26% and the number of cases detected by nucleic acid amplification testing increased 6-fold. The proportion of N. gonorrhoeae isolates with resistance to quinolones increased from 4% to 28% over the same period. Analysis of 695 quinolone-resistant N. gonorrhoeae isolates and 688 quinolone-susceptible control isolates from 2006 showed a higher proportion of men (odds ratio [OR] 3.1, 95% confidence interval [CI] 2.3-4.1) and patients over 30 years of age (OR 3.1, 95% CI 2.4-3.8) in the quinolone-resistant group. The proportion of men who have sex with men appeared to be relatively similar in both groups (OR 1.4, 95% CI 1.1-1.8). Quinolone-resistant strains were more resistant to penicillin (p < 0.001), tetracycline (p < 0.001) and erythromycin (p < 0.001). All isolates were susceptible to cefixime, ceftriaxone, azithromycin and spectinomycin. INTERPRETATION: During 2006 in Ontario, 28% of N. gonorrhoeae isolates were resistant to quinolones. Infections in heterosexual men appear to have contributed significantly to the quinolone resistance rate. Medical practitioners should be aware of the widespread prevalence of quinolone-resistant N. gonorrhoeae and avoid quinolone use for empiric therapy.