Etiological Agents of Urinary Tract Infection and 7 Years Trend of Antibiotic Resistance of Bacterial Uropathogens in Sudan

Bacterial infections of the urinary tract represent a major cause of outpatient visits as well as hospital-acquired infections. As the prevalence of multidrug-resistant uropathogens is increasing, updated knowledge of the commonest bacterial causes and their susceptibility patterns is crucial for the proper selection and use of antimicrobial drugs and the development of effective local prescribing guidelines.

Handling of urine samples, identification of organisms and antimicrobial susceptibility testing were made according to guidelines in Monica Cheesbrough 2000, 2006. The prevalence of resistance of the pathogens against each antibiotic was calculated as the proportion of resistant isolates over the entire tested isolates. Data were analyzed using Epi info; the chi-square test and Fisher exact test were used to assess the statistical significance of results.

In this study, 774 samples were cultured from patients with suspected urinary tract infection (UTI), 705 (91%) urinary isolates showed significant growth (>10⁵ CFU /L) while the other 69 samples showed no significant growth. 431 (61%) of the patients were female, while the other 274 (39%) were males. 13 types of pathogens were identified in 705 urinary isolates. E.Coli was the main bacterial uropathogen identified. Microbiological susceptibility of a total of 28 antibiotics was tested; for each urinary isolate, different sets of these antibiotics were used. 601(96%) of the bacteria were resistant to at least one antibiotic. 17 antibiotics were found to have a bacterial resistance rate of more than 50%, including all B lactams (except cefuroxime), Nalidixic acid, Ciprofloxacin, Norfloxacin, Clindamycin, Co-Trimoxazole and Tetracyclines(Tetracycline and Doxycycline). Other antibiotics were found to have resistance rates of less than 50%. Amikacin & Imipenem had the highest susceptibility rates. Throughout the 7 years, resistance to most of the antibiotics showed an incremental pattern.

Current empirical antibiotic therapy for UTI should be modified, and new guidelines should be established based on local resistance rates. This study comes up with precious regional data for evidence-based empirical antibiotic treatment, but a national sentinel surveillance system and regional antibiograms should be established to track the bacterial susceptibility profiles in Sudan.