Characterisation of Staphylococcus haemolyticus isolated from urinary tract infections

OBJECTIVE: To determine some virulence factors and antimicrobial susceptibilities of Staphylococcus haemolyticus from urinary tract infections. DESIGN: This was a laboratory based cross sectional study on S. haemolyticus isolates from urinary tract infections. SETTING: College of Health Sciences in Harare, Zimbabwe. SUBJECTS: People of all ages with urinary tract infections presenting at health centres in Harare. MAIN OUTCOMEMEASURES: Prevalence of virulence factors and antimicrobial susceptibilities of S. haemolyticus isolates. RESULTS: Deoxyribonuclease (DNase) was produced by 91.8%, delta-haemolysin by 75.5% and slime by 32.7% of the 49 S. haemolyticus isolates. Less than 10% of the isolates produced lipase, alpha haemolysin and protease. All the S. haemolyticus isolates were sensitive to vancomycin and 79.6% to clindamycin. Over 70% of the isolates were resistant to chloramphenicol, co-trimoxazole, erythromycin, oxacillin, ampicillin and penicillin G. Multi-drug resistance to five or more drugs was observed in 69.4% of the isolates. Twenty nine of the 37 isolates that produced delta-haemolysin showed multi-drug resistance. CONCLUSIONS: The virulence factors produced by many S. haemolyticus were DNase and delta-haemolysin. Most of the isolates were resistant to many antimicrobial drugs.