Clinical and microbiological features of resistant gram-negative bloodstream infections in children.

BACKGROUND: Bloodstream infections (BSIs) caused by Gram-negative (GN) bacteria cause significant morbidity and mortality. There is a worldwide increase in the reported incidence of resistant microorganisms; therefore, surveillance programs are important to define resistance patterns of GN microorganisms causing BSIs. The objective of this study was to describe the clinical and microbiological features of resistant GN BSIs in a tertiary pediatric hospital in Turkey. METHODS: Patients between 1 month and 18 years of age hospitalized between January 2005 and December 2012 were included in this study. The presence of ESBL and AmpC type beta-lactamase activity were evaluated using the Clinical and Laboratory Standards Institute (CLSI) disk diffusion and double-disk synergy tests. RESULTS: A total of 209 resistant GN bacterial BSI episodes were identified in 192 patients. Of 192 children, 133 (69.2%) were aged ≤48 months of age. Sixty-six (31.6%) of the BSIs were considered community-acquired and 143 (68.4%) were hospital-acquired infections. The most common isolates were non-fermenting GN bacteria (n=117, 55.9%). The major causative pathogens were Pseudomonas spp. in non-fermenting GN bacteria. The resistance rates to imipenem for Pseudomonas spp. and Acinetobacter spp. were 40.5% and 41.6%, respectively. The most common isolates in fatal patients were Pseudomonas spp. followed by Escherichia coli. The overall 28-day mortality rate was 16.3%. CONCLUSIONS: Although our study was performed at a single center and represents a local population, based on this study, it is concluded that surveillance programs and studies of novel antibiotics for resistant GN bacteria focusing on pediatric patients are required.

Serotype distribution of Streptococcus pneumoniae in children with invasive diseases in Turkey: 2008-2014.

Successful vaccination policies for protection from invasive pneumococcal diseases (IPD) dependent on determination of the exact serotype distribution in each country. We aimed to identify serotypes of pneumococcal strains causing IPD in children in Turkey and emphasize the change in the serotypes before and after vaccination with 7-valent pneumococcal conjugate vaccine (PCV-7) was included and PCV-13 was newly changed in Turkish National Immunization Program. Streptococcus pneumoniae strains were isolated at 22 different hospitals of Turkey, which provide healthcare services to approximately 65% of the Turkish population. Of the 335 diagnosed cases with S. pneumoniae over the whole period of 2008-2014, the most common vaccine serotypes were 19F (15.8%), 6B (5.9%), 14 (5.9%), and 3 (5.9%). During the first 5 y of age, which is the target population for vaccination, the potential serotype coverage ranged from 57.5 % to 36.8%, from 65.0% to 44.7%, and from 77.4% to 60.5% for PCV-7, PCV-10, and PCV-13 in 2008-2014, respectively. The ratio of non-vaccine serotypes was 27.2% in 2008-2010 whereas was 37.6% in 2011-2014 (p=0.045). S. penumoniae serotypes was less non-susceptible to penicillin as compared to our previous results (33.7 vs 16.5 %, p=0.001). The reduction of those serotype coverage in years may be attributed to increasing vaccinated children in Turkey and the increasing non-vaccine serotype may be explained by serotype replacement. Our ongoing IPD surveillance is a significant source of information for the decision-making processes on pneumococcal vaccination.

Bacteremia caused by Pseudomonas luteola in pediatric patients.

Pseudomonas luteola has rarely been reported as a human pathogen. The clinical manifestations of P. luteola bacteremia and its susceptibility to antibiotics have not been characterized. This retrospective study was conducted at a 382-bed tertiary care center in Turkey. During the 9-year study period, 7 patients (5 females and 2 males) were diagnosed with P. luteola bacteremia. Six of these patients had hospital-acquired bacteremia, whereas 1 patient had community-acquired P. luteola infection. All patients had monomicrobial bacteremia. Antimicrobial susceptibility testing revealed that all strains of P. luteola were sensitive to amikacin, gentamicin, trimethoprim-sulfamethoxazole, and meropenem, and that all strains were resistant to piperacillin-tazobactam, aztreonam, and colistin. In conclusion, we believe that P. luteola can cause both community- and hospital-acquired bacteremia. Amikacin, gentamicin, trimethoprim-sulfamethoxazole, and meropenem were effective against P. luteola in the present study.

Meningitis caused by Neisseria Meningitidis, Hemophilus Influenzae Type B and Streptococcus Pneumoniae during 2005-2012 in Turkey. A multicenter prospective surveillance study.

Successful vaccination policies for protection from bacterial meningitis are dependent on determination of the etiology of bacterial meningitis. Cerebrospinal fluid (CSF) samples were obtained prospectively from children from 1 month to ≤18 years of age hospitalized with suspected meningitis, in order to determine the etiology of meningitis in Turkey. DNA evidence of Neisseria meningitidis (N. meningitidis), Streptococcus pneumoniae (S. pneumoniae), and Hemophilus influenzae type b (Hib) was detected using multiplex polymerase chain reaction (PCR). In total, 1452 CSF samples were evaluated and bacterial etiology was determined in 645 (44.4%) cases between 2005 and 2012; N. meningitidis was detected in 333 (51.6%), S. pneumoniae in 195 (30.2%), and Hib in 117 (18.1%) of the PCR positive samples. Of the 333 N. meningitidis positive samples 127 (38.1%) were identified as serogroup W-135, 87 (26.1%) serogroup B, 28 (8.4%) serogroup A and 3 (0.9%) serogroup Y; 88 (26.4%) were non-groupable. As vaccines against the most frequent bacterial isolates in this study are available and licensed, these results highlight the need for broad based protection against meningococcal disease in Turkey.

Distribution of Streptococcus pneumoniae serotypes that cause parapneumonic empyema in Turkey.

Streptococcus pneumoniae is the most common etiological cause of complicated pneumonia, including empyema. In this study, we investigated the serotypes of S. pneumoniae that cause empyema in children. One hundred fifty-six children who were diagnosed with pneumonia complicated with empyema in 13 hospitals in seven geographic regions of Turkey between 2010 and 2012 were included in this study. Pleural fluid samples were collected by thoracentesis and tested for 14 serotypes/serogroups using a Bio-Plex multiplex antigen detection assay. The serotypes of S. pneumoniae were specified in 33 of 156 samples. The mean age ± the standard deviation of the 33 patients was 6.17 ± 3.54 years (range, 0.6 to 15 years). All of the children were unvaccinated according to the vaccination reports. Eighteen of the children were male, and 15 were female. The serotypes of the non-7-valent pneumococcal conjugated vaccine (non-PCV-7), serotype 1, serotype 5, and serotype 3, were detected in eight (14.5%), seven (12.7%), and five (9.1%) of the samples, respectively. Serotypes 1 and 5 were codetected in two samples. The remaining non-PCV-7 serotypes were 8 (n = 3), 18 (n = 1), 19A (n = 1), and 7F/A (n = 1). PCV-7 serotypes 6B, 9V, 14, 19F, and 23F were detected in nine (16.3%) of the samples. The potential serotype coverages of PCV-7, PCV-10, and PCV-13 were 16.3%, 45.4%, and 60%, respectively. Pediatric parapneumonic empyema continues to be an important health problem despite the introduction of conjugated pneumococcal vaccines. Active surveillance studies are needed to monitor the change in S. pneumoniae serotypes that cause empyema in order to have a better selection of pneumococcal vaccines.

A case of newborn with community acquired pneumonia caused by Cupriavidus pauculus.

Cupriavidus pauculus is a gram-negative, aerobic, non-spore forming, non-fermentative motile bacillus. The bacillus can be isolated from water, bottled mineral water, and water from ultrafiltration systems in hospital setting. C. pauculus rarely causes human infections, however it may be an infectious agent especially in immunocompromised individuals. In this report, we present the first case of community acquired pneumonia caused by C. pauculus in a previously healthy newborn who was hospitalized in neonatal intensive care unit on postnatal day 16 because of respiratory distress.

Serotypes of Streptococcus pneumoniae isolates from children with invasive pneumococcal disease in Turkey: baseline evaluation of the introduction of the pneumococcal conjugate vaccine nationwide.

Before use of the pneumococcal conjugate vaccine PCV7 became widespread in Turkey, 202 invasive pneumococcus isolates were analyzed. The most common serotypes were 19F and 6B. In children ≤2 years of age, the potential coverage rate of PCV7 was 69.5%. The most frequent non-PCV7 serotypes were 19A, 3, 1, 6A, and 8.