Nedim Sultan

Nasopharyngeal carriage of Streptococcus pneumoniae in healthy Turkish infants

OBJECTIVES The aims of this study were to determine nasopharyngeal carriage rates, serotype distribution and antimicrobial resistance patterns of Streptococcus pneumoniae in healthy 0 to 2 year-old infants who live within a rural or urban locale and not attending daycare centers. In order to evaluate the possible impact of pneumococcal conjugate vaccine in this population, coverage of the isolated serotypes by the vaccine was also calculated. METHODS The study was conducted on 564 healthy infants attending 2 different well child clinics, one of which is located in an urban region and the other in a rural region. Specimens were collected with nasopharyngeal swabs. Serotyping was performed with standard antisera. Penicillin susceptibility was determined with E-test. Chi-square tests and logistic regression were used for data analysis. RESULTS The pneumococcal carriage rate was 22.5%. Age (>2 months age) [2.98 (1.41-6.29) p=0.004] and presence of another child within the house who attends school [1.72 (1.13-2.62) p=0.01] increased the carriage rate. The most frequently isolated serotypes were 11 (11.8%), 23 (7.9%), 19F (7.1%), 22 (6.3%), 9 (5.5%), 19 (5.5%) and 23B (5.5%). The total coverage of vaccine and vaccine-related serotypes by 7, 11 and 13 valent pneumococcal conjugate vaccines were 51.2, 59.0 and 59.0%, respectively. Of the isolated pneumococci, 10 (8.5%) were intermediately resistant and 8 (6.8%) were highly resistant to penicillin. CONCLUSION This study provides data about the local carriage rate and serotype distribution of S. pneumoniae strains in Turkish children, which is important in predicting the possible effects of different valent pneumococcal conjugate vaccines in this population.

Effect of timing of glutamine-enriched enteral nutrition on intestinal damage caused by irradiation.

Intestinal mucosal damage and bacterial translocation are clinical problems that may be caused by the use of ionizing radiation. Glutamine (Gln) support reduces the mucosal barrier in several ways. This study was undertaken to investigate the effect of timing of Gln-enriched enteral nutrition (EN) on bacterial translocation and mucosal damage due to radiotherapy (RT). A rat model of whole body irradiation was designed in which a single dose of 485 cGy was given. A total of 50 rats were randomly assigned to the following 5 groups, each of which comprised 10 rats: (1) balanced rat chow given for 8 days without RT (group 1); (2) balanced rat chow given 4 days before and 4 days after RT (group 2); (3) Gln-enriched EN given 4 days before RT (group 3); (4) Gln-enriched EN given 4 days after RT (group 4); and (5) Gln-enriched EN given 4 days before and 4 days after RT (group 5). Mesenteric lymph node and ileum samples were removed for evaluation of bacterial translocation (BT) and histopathologic investigation, respectively. BT and intestinal mucosal injury scores in all rats that received RT were higher than in rats without RT. No difference was seen in parameters between groups 3 and 4 (P>.05, P>.016, respectively); BT and intestinal mucosal injury scores of group 5 were significantly lower than those of groups 3 and 4 (P<.05, P<.016, respectively). Meanwhile, the BT and mesenteric injury scores of group 5 were significantly lower than those of group 2 (P<.05, P<.016, respectively). As a result, intestinal injury due to RT was significantly decreased by Gln-enriched EN support given before and after whole body RT.

Preliminary results of a novel quorum sensing inhibitor against pneumococcal infection and biofilm formation with special interest to otitis media and cochlear implantation

Abstract The purpose of the study is to assess the effect of a novel quorum sensing inhibitor (QSI), coded as ‘yd 47’, against otitis media and biofilm formation on Cochlear implants (CIs). Small pieces cut from cochlear implant were implanted under the skin in the retroauricular area on both sides of four guinea pigs. The implant pieces in the study and control sides were implanted in Streptococcus pneumoniae strain solution and saline, respectively. The right and left middle ears were also instilled with a solution containing pneumococci and saline, respectively. The animals were only given an intraperitoneal ‘yd 47’ twice daily for three months to be assessed later with electron microscopy. Clinical examination with palpation, inspection and otoscopy did not reveal any sign of implant infection or otitis media. In the study and control implant materials, soft tissues around the implant and tympanic membranes, there was no biofilm formation by pneumococci. Contamination by various cells and some rod-shaped bacteria (not diplococcic) were seen in some of the materials. In conclusion, the novel QSI seems promising in the prevention of otitis media and biofilm formation on CIs by pneumococci.

Drug resistance profiles and clonality of sporadic Shigella sonnei isolates in Ankara, Turkey

The aims of this study were to investigate drug resistance rates, types of extended spectrum beta lactamases (ESBLs), and molecular epidemiological characteristics of 43 Shigella sonnei isolates. Ampicillin-sulbactam, amoxicillin-clavulanate, chloramphenicol, and ciprofloxacin were the most active antibiotics. Five isolates harbored blaSHV-12, blaTEM-1 and blaCTX-M-15. More than 90% of the isolates had an indistinguishable pulsotype.