Biochemical and bacteriological profiles of asymptomatic bacteriuria among school children in Ago-Iwoye, Nigeria

Abstract

Background: Asymptomatic bacteriuria (ASB) in children is a predisposing factor to symptomatic urinary tract infection (UTI) that may be complicated by blood stream infections if not appropriately treated with resultant mortality or morbidity. The objectives of this study are to determine the prevalence of ASB, and evaluate both biochemical and bacteriological characteristics of urine samples of primary school pupils in Ago-Iwoye, Ijebu North Local Government Area (LGA), Ogun State, Nigeria.

Methodology: Three hundred and seventy-two (186 males and 186 females) apparently healthy (asymptomatic) pupils aged 2-16 years from four randomly selected primary schools in the LGA were screened for ASB. Clean catch specimen of midstream urine was collected from each subject. Biochemical analysis of the urine was performed with Combi 10 reagent strip. MacConkey and Cysteine Lactose Electrolyte Deficient (CLED) agar plates were inoculated with calibrated wireloop delivering 0.01 ml of urine for aerobic culture at 37^oC for 24 hours. Identification of significant bacteria on culture plates was done using conventional biochemical tests.

Results: The frequency of clear, slightly turbid and turbid urine were 31 (8.3%), 99 (26.6%) and 56 (15.1%) respectively. All analyzed urine samples were alkaline and negative for ketone, glucose and blood, but contained protein in 230 (61.8%), bilirubin in 184 (49.5%), nitrites in 64 (17.2%) and urobilinogen in 14 (3.7%) subjects. The prevalence of significant bacteriuria was 11.8% (44 of 372) with 7.0% in males and 16.7% in females (p = 0.0063). The frequency of bacteria isolated in descending order were Escherichia coli 61.4%, Staphylococcus saprophyticus 61.4%, Staphylococcus aureus 45.5%, Bacillus subtilis 45.5%, Enterococcus faecalis 43.2%, Enterobacter spp 36.4%, Serratia marscencen 31.8%, Klebsiella pneumoniae 22.7%, Proteus mirabilis 22.7% and Pseudomonas aeruginosa 20.5%.

Conclusion: This result highlights the presence of significant bacteriuria among apparently healthy pupils in the study area, with higher prevalence in the female pupils. The apparent risk of developing symptomatic UTI with the attendant complications in these pupils should spur preventive education of parents/guardians and the general populace about this entity.

Keywords: Asymptomatic bacteriuria, S. saprophyticus, morbidity, prevalence, primary school pupils