Antimicrobial sensitivity pattern, demographic findings and risk factors amongst meningitis and non-meningitis invasive Streptococcus pneumoniae at Aga Khan University Hospital Clinical Laboratory, Karachi, Pakistan.

Objective: To determine the resistance rate of penicillin and ceftriaxone amongst invasive meningitis and nonmeningitis isolates of streptococcus pneumoniae.

Methods: The prospective cross-sectional study was conducted from January 2011 to March 2014 at the Clinical Microbiology Laboratory of Aga Khan University, Karachi, and comprised all invasive strains of streptococcus pneumoniae. Penicillin and ceftriaxone susceptibilities were performed and interpreted based on minimum inhibitory concentration breakpoints recommended by Clinical and Laboratory Standards Institute guidelines. Data was analysed using Stata 12.

Results: There were 163 strains isolated from sterile body fluids of 109 patients. Of the total, 46(28%) samples were meningitic while 117(72%) were non-meningitic. Of the meningeal isolates, 12(26%) were resistant to penicillin, while none was resistant to ceftriaxone and vancomycin. None of non meningeal isolates showed resistance to penicillin, ceftriaxone or vancomycin.

Conclusion: There was considerable penicillin resistance among meningeal strains of streptococcus pneumoniae, but here appeared to be no need to add vancomycin for empirical treatment of invasive streptococcus pneumonia infection.