Molecular characterization, antibiotic resistance pattern and capsular types of invasive Streptococcus pneumonia isolated from clinical samples in Tehran, Iran

Abstract

Background: Streptococcus pneumoniae causes serious infections worldwide. The aim of this study was to determine the molecular characteristic, antibiotic resistance pattern and capsular types of invasive S. pneumonia in Tehran, Iran. Results: Of the 44 pneumococcal invasive isolates, 39 (89%) were isolated from children and 5 (11%) from adults. The results show that all pneumococcal isolates were susceptible to linezolid but had varying resistance to trimethoprim-sulfamethoxazole (86%), erythromycin (73%), tetracycline (66%), clindamycin (43%), penicillin (16%), chloramphenicol (14%) and levofloxacin (2%). The range of erythromycin, tetracycline and penicillin MICs were 2 - ≥ 256 μg/mL, 4 - ≥ 48 μg/mL, and 0.047 - ≥ 256 respectively. All of the penicillin resistant isolates were multidrug resistant (MDR) and in addition to penicillin were resistant to tetracycline, erythromycin and trimethoprim-sulfamethoxazole. The most common capsular types detected in 64% of the pneumococcal isolates was 6A/B, 19A, 15A, 23F. The multilocus sequence typing (MLST) of 10 pneumococcal isolates revealed 9 different sequence types (STs), including ST 15139 (capsular type 19A) and ST 15140 (capsular type 23F), which have not previously been reported.Conclusions: The study revealed that the S. pneumonia isolates belonged to diverse capsular types and clones with high rate of resistance to erythromycin, tetracycline, and penicillin.

Tỷ lệ phân lập, đề kháng kháng sinh của streptococcus pneumoniae gây viêm phổi nặng ở trẻ em Cần Thơ

“…4 Tương tự, sự xuất hiện của các chủng S. pneumoniae đa kháng cũng khiến việc điều trị bệnh do S. pneumoniae trở nên khó khăn hơn. 5…”