Antimicrobial Resistance in Isolates of Streptococcus pneumoniae during January 2016 to December 2017 in Dr. Lal Path Labs, Delhi

Aims and Objectives: The aim and objectives of this study is to assess drug resistance pattern of Streptococcus pneumoniae in Dr Lal Path Labs, Delhi. We did retrospective study from January 2016 to December 2017 on 86 isolates of Streptococcus pneumoniae.

Materials and Methods: At study sites, total 86 isolates from pulmonary and extra pulmonary grown on Columbia 5% sheep Blood agar (BioMerieux) plates after incubation for 24 to 48 hours at 36± 1°C in 5% CO2 incubator. Identified by MALDI TOF-MS (Bruker Daltonics) & Antibiotic susceptibility testing were also done using VITEK® 2 GP card. / S. pneumoniae susceptibility card (AST ST01 Card –BioMerieux, India) as per as CLSI M100-S-28.

Results: A total 86 isolates from pulmonary (21%) and extra pulmonary (79%) specimens were analysed for their antibiotic resistance pattern. 30% were from samples collected from children below between 0-10 years and 17.4% were collected from adults above 60 years of age.

The most prevalent source was blood (45.34%), followed by Sputum (20.93%), CSF (12.79%), Pus (n= 9.3%) throat (4.76%), ear (3.5%), nasal (2.3%) and eye (1.19%).

Evaluating the antimicrobial susceptibility with 12 antibiotics we found strains were most susceptible to Chloramphenicol (98.8%), Linezolid (93%) and Vancomycin (88.37%). However most resistance were seen in Erythromycin (62.8%), Tetracycline (59.3%), Co-trimoxazole (62.8%) and Penicillin resistance were (22.1%).

Discussion and Conclusion: In our study we found the infection is most common in extremes of age i e: 30% (0-10 y) & 17.4% (60-80y). Alarming thing found is the emergence of resistance in Vancomycin (11.62%) and Linezolid (6.97%) in India which is also reported by other studies.

We found Chloramphenicol and Linezolid are most susceptible drugs against Streptococcus pneumoniae whereas maximum resistance was observed for Erythromycin (62.8%), Tetracycline (59.3%), Co-trimoxazole (62.8%) and Penicillin resistance is very much present in pulmonary isolates in comparision to extrapulmonary isolates.