Urine culture contamination: a one-year retrospective study at the national hospital, abuja

Abstract

Background: Urine culture contamination is a significant cause of delay in treatment of patients being investigated for urinary tract
infection. Though contamination is not completely avoidable, several measures have been proven to decrease contamination rates.
There are few studies detailing urine contamination rates in laboratories in Nigeria.
Aim: To determine the frequency and factors associated with urine culture contamination in samples submitted to the Medical
Microbiology Laboratory in National Hospital Abuja (NHA).
Method: Retrospective study of urine culture contamination in which data from Medical Microbiology Laboratory from January 1 to
December 31 2012 at National Hospital Abuja were reviewed. Patients’ age, gender, location and urine culture result were assessed.
Contamination rates for different genders, age groups and departments were assessed and results presented in simple averages and
percentages.
Results: Overall contamination rate was 13.1%. Females had a contamination rate of 16.9%, which was significantly higher than the
contamination rate of 6.8% in males. The Gynaecology and Antenatal clinics had the highest contamination rates amongst departments
with 22.5% and 21.3% respectively. Lowest contamination rates were in Emergency Paediatric Unit (EPU) and intensive Care Unit (ICU)
with rates of 5.9%and 9.5% respectively. The female gender was found to be the most significant predictor of higher contamination rate.
Conclusion: Contamination rate of urine cultures in this study is unacceptably high. Appropriate interventions need to be instituted to
reduce the current urine culture contamination rate in National Hospital Abuja.

Key Words: Urine, Contamination, National Hospital, Abuja.