Hospital and community isolates of uropathogens at a tertiary hospital in South Africa

• Published in: South African medical journal 2009-08, Vol.99 (8), p.584-587
• Main Authors: HABTE, T. M, DUBE, S, ISMAIL, N, HOOSEN, A. A
• Format: Article
• Language: English
• Subjects: Adult; Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Bacteriuria - microbiology; Biological and medical sciences; Care and treatment; Drug Resistance, Multiple, Bacterial; Enterococcus faecalis - drug effects; Enterococcus faecalis - isolation & purification; Escherichia coli - drug effects; Escherichia coli - isolation & purification; Female; General aspects; Health aspects; Hospitals; Hospitals, Teaching; Humans; Klebsiella - drug effects; Klebsiella - isolation & purification; Male; Medical sciences; Microbial Sensitivity Tests; Proteus - drug effects; Proteus - isolation & purification; Public health; Retrospective Studies; South Africa; Urinary tract infections; Urinary Tract Infections - drug therapy; Urinary Tract Infections - microbiology; Urine - microbiology
• ISSN: 0256-9574

To investigate the profile of common uropathogens isolated from urine specimens submitted to the diagnostic microbiology laboratory at a tertiary teaching hospital and assess their antimicrobial susceptibility patterns to commonly used antimicrobial agents. We conducted a retrospective analysis of laboratory reports for all urine specimens submitted for investigations over a 1-year period. Isolates were tested by means of the Kirby-Bauer disc diffusion method for susceptibility to amoxicillin, ciprofloxacin, gentamicin, co-trimoxazole and nitrofurantoin, and for extended-spectrum beta-lactamase (ESBL) production. Out of the total specimens (N=2,203) received over the 1-year study period, 51.1% (1,126) of the urine samples were culture-positive, the majority (65.4%) having come from females. The most common isolate was Escherichia coli (39.0%) followed by Klebsiella species (20.8%) and Enterococcus faecalis (8.2%). The Gram-negative isolates displayed a very high level of resistance to amoxicillin (range 43 - 100%) and co-trimoxazole (range 29 - 90%), whereas resistance to gentamicin (range 0 - 50%) and ciprofloxacin (range 0 - 33%) was lower. E. coli isolates were susceptible to nitrofurantoin (94%), and ESBL production was significantly higher (p=0.01) in the hospital isolates, compared with those from the community referral sites. The culture-positive rate for uropathogens was high, with a greater incidence among females. E. coli was the most common aetiological agent identified, and remained susceptible to nitrofurantoin. Resistance levels to amoxicillin and co-trimoxazole were very high for all Gram-negative isolates, and it is recommended that these antibiotics should not be used for the empiric treatment of urinary tract infections.