5 | Page Available online at http:/ / www.ijmb.bret.ac.in ASYMPTOMATIC BACTERIURIA AND ANTIMICROBIAL SUSCEPTIBILITY OF STAPHYLOCOCCUSAUREUSFROM UNIVERSITY STUDENTS IN KEFFI, NIGERIA Ngwai YB and Bakare OR Microbiology Unit, Nasarawa State University, P.M.B. 1022, Keffi, Nasarawa State, Nigeria ARTICLE INFO ABSTRACT Article History: Received, 10th ,Novemer,2011 Received i n r evi sed for m, 10 th ,December ,2011 Accepted, 30 th ,Dcember ,2011 Published online, 30 th ,Januar y ,2012 Asymptomatic bacteriuria occurs frequently and it is a major criterion of urinary tract infection. This study investigates bacteriuria and the antimicrobial susceptibility of Staphylococcus aureus isolates from urine of asymptomatic students of Nasarawa State University, Keffi, Nigeria. In this study, three hundred mid-stream urine samples were collected from consenting asymptomatic male and female students of Nasarawa State University, Keffi. Bacterial load of each urine sample was determined by spread plate count; and S. aureus was isolated from the urine on mannitol salt agar and identified by biochemical tests. Antimicrobial susceptibility of the isolates was tested to commonly used antibiotics by standard procedures. Sixty (60, 20%) urine samples showed significant S. aureus bacteriuria, with higher prevalence in males (35, 23.3%) than in females (25, 16.7%). The isolates were most susceptible to gentamicin (36.7%), chloramphenicol (33.3%) and streptomycin (33.3%); and least to amoxicillin-clavulanic acid (13.3%). Most (91.7%) of the isolates were multiply resistant to antimicrobial agents, with joint resistance to six drugs being the most common (29.1%). All multiple antibiotic resistance indices were above 0.2 suggesting isolates to have originated from environment where antibiotics are freely available and misused. In conclusion, the outcome of this study highlights the need to investigate the bacteriuria status of students, particularly new entrants, and treat cases detected to avoid such students incubating asymptomatic infection that degenerate into symptomatic urinary tract infection. © Copy Right, IJMBS, 2011, Bret Research Journals. All rights reserved. Key words: Asymptomatic, Bacteriuria, Staphylococcus aureus, Susceptibility INTRODUCTION The presence of bacteria in urine without symptoms normally associated with urinary tract infection (such as pain, frequency and urgency) is called asymptomatic bacteriuria. It may result from contamination during or after collection of urine, or it may indicate the presence of bacteria in the urinary bladder. Forbes et al, (2002) defines significant bacteriuria as urine containing bacteria count of 10 5 cfu /mL of voided midstream urine aseptically collected in an individual without symptoms of urinary tract infections. Asymptomatic bacteriuria occurred more frequently in females as compared with males and it is a major criterion of urinary tract infection (Nurullaev, 2004). Reasons adduced to this include shorter and wider urethra and its proximity to the anus in the females (Sheffield and Cunningham, 2005). Bacteria may invade the urinary tract and multiply resulting in infection known as urinary tract infection (UTI). Stamm (2002) defines UTI as a clinical (symptomatic) or sub-clinical (asymptomatic) disease that may involve just the lower tract or both the lower and the upper tracts. Infection may involve single site such as urethra (as in urethritis), prostate (as in prostitis), bladder (as in cystitis), and kidney (as in pyelonephritis); but the whole urinary system is always at a risk of invasion by bacteria once any part is infected (Atlas, 1986). UTI are among the most common bacterial infections acquired in the community and in hospitals (Foxman, 2010); and are frequently caused by Escherichia coli, Staphylococcus aureus, Proteus spp, Klebsiella spp and Pseudomonas aeruginosa (Todar, 2008; Mbata, 2007; Ebie et al., 2001; Eva et al., 1990; Foxman, 1990; Burbige et al., 1984). In Nigeria, E. coli, Proteus spp and Klebsiella spp have been isolated in 90% of UTI reposted cases (Ehinmidu, 2003; Obaseiki-Ebor, 1988; Sever et al., 1985); Olanipekun and Montefiore, 1978). UTI affects all age groups from neonates to geriatrics; with some predisposing factors such as sex, age, pregnancy, obstruction of urinary flow and underlying diseases International Journal of Microbiology and Bioinformatics - Vol. 2, Issue, 1, pp. 5 - 8, January, 2012 INTERNATIONAL JOURNAL OF MICROBIOLOGY AND BI OINFORMATICS RESEARCH ARTI CLE