A Study on Microbiology of Urinary Tract Infection at Tribhuvan University Teaching Hospital Kathmandu Nepal

Abstract

A study was conducted among patients suspected of UTI attending outpatients departmentand hospitalized patients of Tribhuvan University Teaching Hospital, Katmandu, Nepal.The study was conducted for three months from June 2006 to August 2006. The objectivesof the study were to isolate bacteria causing UTI, to correlate bacteriuria with pyuria, todetermine antibiotic susceptibility pattern of isolated organisms and to analyze the MDRstrains. One hundred and eighty five midstream urine samples collected were investigated byconventional semi-quantitative culture technique, microscopy and antibiotic susceptibilitytest. Only 22.16% (41/185) of the samples showed significant bacterial growth. Slightly greaterprevalence of bacteriuria was found in males (24.67%) than in females (20.37%) and higherin inpatients (29.09%) than in outpatients (19.23%).Statistically it was found that there wasno significant association of significant bacteriuria in males and females (P>0.05). Similarlyassociation of presence of bacteriuria and hospitalization of patients was also found out tobe statistically insignificant (P>0.05). Status of bacteriuria was found higher in age group20-30 (19.51%) followed by 30-40 (17.07%) in female and 9.75% in 20-30 and 50-60 yearsin male patients. Eight different species of bacteria were isolated among whichEscherichia coli (65.85%)was the most predominant isolate followed byKlebsiellaspecies(K. pneumoniaeandK.oxytoca) (12.19%), Staphylococcus aureus(7.32%),Pseudomonas aeruginosa(4.88%),Streptococcus faecalis (4.88%). The other organisms isolated were Proteus vulgaris(2.44%) andEnterobacterspecies(2.44%). Predictors concerning pus cell count (5/HPF) and erythrocytes count (3/HPF) wereanalyzed to determine the positive predictive value (PPV) relation to the significantbacteriuria. PPV for pus cell count was found to be higher (54.38%) than that of RBCcount(27.27%). Gram-negative bacilli (excludingPseudomonas aeruginosa,Klebsiella oxytoca, Klebsielllapneumoniae) showed best susceptibility towards Nitrofurantoin(58.33%) followed byCeftriazone (50%) . Amikacin was also effective as Nitrofurantoin against Pseudomonasaeruginosa, K. oxytoca,andK. pneumoniae.The most effective antibiotic to overall gram-positive bacteria was found to be Novobiocin (100%) and Erythromycin (60%). Multidrug resistance was observed in 56.09% (23/41) bacterial isolates ofwhich the mostpredominant wasEcherichia coli 62.96% ( 17/27) and that inKlebsiella pneumoniaewas50%(2/4) .