Comparison between Chromogenic Colour Agar and Biochemical Tests in the Identification of Causative Organism of Bacteriuria Associated with Urinary Schistosomiasis, in Abu Rukba Village, White Nile State (Sudan)

Abstract

Chromogenic medium is culture media for simple and fast detection of bacteria using chromogenic substrates, resulting in the different coloration of certain bacteria colonies. Have several advantages over traditional media, such as cysteine-lactose-electrolyte deficient (CLED) medium, allow for easier recognition of mixed growth, save time, reduce workload and provides higher detection rates. To compare between chromogenic colour agar and biochemical tests in identification of organisms causing bacteriuria that associated with urinary Schistosomiasis. The study was conducted in Abu Rukba village in the White Nile State, Sudan. The study was carried out on the entire population of the village (1029 individuals) during the period of November 2011 and November 2013. Urine samples were collected from study population after having their informed consent, school staff and local administrators. A total of 1029 Mid-stream urine specimens were collected aseptically as possible, in a sterile wide mouth container in the morning and processed by the laboratory within 2 hours of collection, or were kept refrigerated at 4ºC until delivery to the laboratory and were processed no longer than 4 hours after collection. Each specimen was routinely processed using the centrifugation technique to detect Schistosoma and cultivated by using chromogenic agar and Cystine Lactose Electrolyte Deficient agar plate (CLED) then identified by biochemical tests. Antibiotic susceptibility also was done. Bacterial culture for those who were positive for S. haematobium infection (594) revealed growth of Staphylococcus aureus in 116 urine samples (19.5%), Enterococcus faecalis in 57 (9.6%), Escherichia coli in 28 (4.7%), Klebsiella pneumoniae in 20 (3.4%), Proteus species in 2 (0.4%) and mixed infection in 71 (11.9%). Comparing the chromogenic media results with the biochemical reaction results, 95.5% of all isolates were recovered on both. The remaining 4.5% of isolates were different by both tests. Chromogenic medium provided a reliable alternative to CLED medium and biochemical tests for the routine culture of urine specimens.