Antibiotic Susceptibility Patterns of Staphylococcus Aureus with Special Reference to Methicilin Resistance- A Preliminary Report

Abstract

One hundred strains of Staphylococcus aureus isolated from various clinical samples
were screened for methicillin resistance by the disc diffusion technique. Antibiotic
susceptibility pattern of Methicillin sensitive S. aureus (MSSA) and Methicillin resistant
S. aureus (MRSA) against a number of antibiotics like penicillin, ampicillin,
gentamicin, erythromycin, tetracycline, Coamoxyclav cotrimoxazole, ciprofloxacin,
cefalothin and vancomycin are compared. 20% of the strains were found to be MRSA
while 80% were MSSA. The isolation rate of MRSA from indoor (hospital acquired)
and outdoor (community acquired) was 18% and 2% respectively. Drug resistance of
MRSA was highest with penicillin (100%), followed by erythromycin (80%), ampicillin
and gentamicin (65%), tetracycline (60%), cotrimoxazole (55%), cefalothin (20%),
Coamoxyclav (15%) and least against ciprofloxacin (5%) and vancomycin (0%). The
MSSA were sensitive to vancomycin (100%), ciprofloxacin (100%), Coamoxyclav
(96.25%), and cephalothin (82.5%) while sensitivity to tetracycline (78.75%),
gentamicin (75%), erythromycin (40%), ampicillin (38.75%), cotrimoxazole (37.55)
and penicillin (21.25%) was much lesser. This study emphasizes the need for constant
monitoring on the prevalence of MRSA and its microbial susceptibility pattern as the
data would help clinicians in the effective management of nosocomial infections caused
by S.aureus.

Key Words: Staphylococcus Aureus, Methicillin, Sensitive, Resistant, Nosocomial Infection.