Antibiotic susceptibility of Staphylococcus aureus in suppurative lesions in Lacor Hospital, Uganda

Staphylococcus aureus, a mainly acquired hospital infection is responsible for many suppurative lesions and has demonstrated the ability of developing resistance to many antimicrobial agents leading to life threatening infections and long hospital stay.

To determined the prevalence and antibiotic susceptibility of Staphylococcus aureus in suppurative lesions of the surgical ward and outpatients of Lacor Hospital (Uganda).

A cross-sectional study was conducted at St. Mary's Hospital Lacor to determine the prevalence and antibiotic susceptibility profiles of Staphylococcus aureus in suppurative lesions in both surgical inpatients and outpatients. Using culture techniques on MacConkey and blood agar, Staphylococcus aureus was isolated based on the colonial characteristics and confirmed by Catalase and tube Coagulase tests. The antibiotic susceptibility test was done using Kirby-Buer disk diffusion method on 4% Salt Muellar Hinton II agar for the Methicillin and non salted Muellar Hinton II agar for the other antibiotics (NCCLS M100S9).

The prevalence of Staphylococcus aureus in 122 patients sampled was 59.4% for the surgical inpatients and 48.3% for outpatients giving an average prevalence of 53.9% for both groups of patients. The average antibiotic susceptibility patterns for the 8 antibiotic tested were: Ampicillin (75.0%), Chloramphenicol (34.4%), Ciprofloxacin (1.6%), Erythromycin (7.8%), Gentamycin (0%), Methicillin (1.6%), Tetracycline (45.3%) and Co-trimoxazole (50.0%). The resistance in surgical inpatients was significantly higher than outpatients (t=1299, p<0.05) and Methicillin resistance was confirmed by PCR.

Staphylococcus aureus is highly prevalent and more resistant in inpatients. There is a higher risk of acquiring drug resistant staphylococcus aureus infection in inpatients of Lacor Hospital with a Methicillin resistance of 0% and 2.6% for out and inpatients respectively.