Abstract

Enterobacter sakazakii (E. sakazakii) has been identified as emerging opportunistic pathogens that can cause enterocolitis, bacteraemia, meningitis, brain abscess, and urinary tract infection. They have been particularly associated with meningitis in neonates where infant milk formulae have been epidemiologically linked to the disease. This study was carried out during the period of November 2008 to March 2009; to determine the occurrence of E. sakazakii in clinical specimens and its resistance to traditionally used antimicrobial agents in the Sudan. A total of 389 (311 urine specimens, 11 wound specimens, and 67 stool specimens) were collected from outpatients of three leading hospitals in Khartoum State. The urine specimens and wound swabs were cultured on blood and MacConkey's agars for primary isolation of pathogen, while stool specimens were cultured on selenite F broth and incubated overnight then subcultured on xylose lysine deoxycholate agar. Identification of the E. sakazakii was done by colonial morphology, Grams stain and biochemical tests using API 20E. Modified Kirby-Bauer disc diffusion method was adopted to determine the resistance rate of E. sakazakii to fifteen antimicrobial agents. Minimum inhibitory concentration (MIC) of antimicrobial agents was determined by E-test. The result showed that out of 389 specimens examined, 6 (1.5%)E. sakazakii were recovered, 4 (1.03%) from urine, 1(0.3%) from wound and 1(0.3%) from stool. The results more over revealed that the antimicrobial resistance of E. sakazakii was as follows; ceftazidime, amoxicillin, amoxyclav (100% each), co-trimoxazole, ticarcyline (83.3% each), chloramphenicol, tetracycline, ceftriaxone, nitrofuratoin, cephotaxime, tobramycin (66.7% each), ciprofloxacin, amikacin and nalidixic acid (16.7% each). None of the isolates were found to be resistant to gentamicin. In addition to that, the result indicated that the MIC, MIC₅₀ and MIC₉₀ of different antimicrobial agents range from 0.001 to > 240, 0.1 to > 240 and 0.5 to > 240 µg/ml respectively. The results indicated for the first time the presence of E. sakazakii in the examined clinical specimens in Sudan. The occurrence was high and the antimicrobial resistance of the isolated E. sakazakii was also high.

Key words: Enterobacter sakazakii, API 20E, E-Test, Khartoum, Sudan.