Beta-lactamase Induction in Nosocomial Staphylococcus aureus Strains Cultured from the Nasal Cavity and Wound of Patients

The study was conducted to determine Beta-lactamase induction in Staphylococcus aureus strains cultured from the nasal cavity and surgical wounds of in- patients at a tertiary teaching hospital.

Swab samples were taken from the nasal cavity -wound pair of 110 consented patients. The S. aureus isolates were identified and the antibiotics susceptibility tests were conducted using standard protocols. Beta-lactamase induction was assayed with the micro-iodometric method. The data obtained were statistically analysed.

A total of 81 S. aureus isolates were cultured from the nasal cavity and wounds of the 110 samples collected. Beta-lactamase was produced by 14 (41.2%) and 26 (55.3%) of the isolates cultured from the nasal cavity and wounds respectively. Constitutive and induced Beta-lactamase production was observed.

Beta-lactamase production in the isolates is not dependent on antibiotic exposure alone. The findings underscore the need for appropriate infection control and adequate hygiene practices to prevent the spread of S. aureus in the hospital settings.