Antibiotics susceptibility pattern of Streptococcus pneumoniae isolated from sputum cultures of human immunodeficiency virus infected patients in Yaoundé, Cameroon

Abstract

Introduction: the susceptibility of Streptococcus pneumoniae to commonly used antibiotics is threatened by the emergence of resistance of S. pneumonia strains. So, to improve the management of lower respiratory tract infections (LRTIs) in human immunodeficiency virus infected patients, we assessed the antibiotic susceptibility of Streptococcus pneumoniae which is the most common bacterial cause of LRTIs in patients.

Methods: a cross sectional study was carried out from May to October 2014. HIV infected patients suspected of LRTIs attending the Center Medical laboratory and those followed up at the authorized treatment center of Yaounde Military Hospital in Cameroon were enrolled. Sputum was collected from each patient and cultured; identification of microorganisms was performed following standard methods. The disk diffusion method was used for antibacterial susceptibility testing according to the Antibiogram Committee of French Society for Microbiology guidelines.

Results: a total of 51 (25.5%) isolates of S. pneumoniae were recovered from sputum samples obtained from 200 HIV infected patients aged 19-66 years old (mean age: 36±10.087 years old); 144 (72%) of them were female (sex ratio M/F: 1/3). S. pneumoniae carriage was not age dependent (P = 0.384) and was significantly higher in male compared to female (P = 0.008). S. pneumoniae isolates were susceptible to amoxicillin-clavulinic acid (100%), pristinamycin (100%), erythromycin (100%) and cefixime (98.04 %). Highest resistance rates were recorded with fusidic acid (100%), fosfomycin (100%) and tetracyclin (100%).

Conclusion: S. pneumoniae is still susceptible to some agents in our study area however; ongoing surveillance for antimicrobial susceptibility remains essential to identify emerging resistance and attempt to limit its spread.