RESISTANCE EMERGENCE OF DOXYCYCLINE AGAINST STAPHYLOCOCCUS AUREUS AND STREPTOCOCCUS PNEUONIAE

Abstract

Objective: To determine the in vitro sensitivity pattern of doxycycline against the common pathogens namely Staphylococcus aureus and Streptococcus pneumoniae. Study Design: Cross-sectional study. Place and Duration of Study: Various clinical/pathological laboratories of Karachi Pakistan, from Jun 2016 to Sep 2016. Methodology: One hundred and ten clinical isolates of Staphylococcus aureus and 50 isolates of Streptococcus pneumoniae were taken from throat, blood, skin pus, and sputum of patients. Susceptibility of the isolates against the doxycycline was determined through Kirby-Bauer disk diffusion technique. Zone of inhibition appeared around the disks was measured and analyzed as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Data was analyzed using SPSS version 20. Results: About 65.4% of Staphylococcus aureus and 62.0% of Streptococcus pneumoniae were found to be sensitive towards doxycycline (p<0.05). Conclusion: Sensitivity of the doxycycline for Staphylococcus aureus and Streptococcus pneumonia has been decreasing with time. The drug was observed to possessed little higher activity against Staphylococcus aureus than Streptococcus pneumoniae.