Detection of Serotype Distribution and Drug Resistance of Streptococcus Pneumoniae Isolated From Pediatric Patients.

Abstract

To analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from pediatric patients in a Chinese hospital. From October 2011 to May 2014, we collected 284 isolates (including 217 noninvasive and 67 invasive strains). We tested the antimicrobial susceptibility of these specimens using the Epsilomer test and disk diffusion method, and the expression of macrolide resistant genes ermB and mefA by polymerase chain reaction. The most common serotype for 217 noninvasive strains was 19F (31.3%). The coverage rates of the 7-, 10-, and 13-valent pneumococcal conjugate vaccines (PCV7, PCV10, and PCV13) were 53.9%, 53.9%, and 86.2%, respectively. For 67 invasive strains, the most common serotype was 23F (22.4%). The coverage rates of PCV7, PCV10, and PCV13 for invasive strains were 77.6%, 82.1%, and 91.0%, respectively. The susceptibility of strains isolated from nonmeningitis specimens to penicillin (PEN) was 97.2%. The rate of multidrug resistance in 284 isolates was 98.7%. All of these isolates were resistant to erythromycin (ERY) and had the ermB gene; 38.6% of those isolates had the mefA gene. Compared with PCV7 and PCV10, the coverage rate of PCV13 was relatively higher for the S. pneumoniae isolates from pediatric patients. This finding suggests that PCV13 probably plays the strongest role in prevention of pneumococcal diseases and control of multidrug resistance. Because pneumococci were sensitive to PEN, this drug is still the preferred choice for clinical treatment of pediatric pneumococcal diseases.