Prevalence, Risk Factors and Antimicrobial Resistance of Asymptomatic Bacteriuria Among Antenatal Women

Abstract

Background: Asymptomatic bacteriuria (ABU) in antenatal women is microbiological diagnosis and if untreated have 20-30 fold increased risk of developing pyelonephritis during pregnancy.

Aim: The prospective study was conducted to determine the prevalence, risk factors and antibiotic resistance related to ABU in antenatal women.

Subjects and Methods: A total of 287 asymptomatic pregnant women who attended the antenatal clinic at a tertiary care hospital, Odisha, India from July 2012 to December 2012 were enrolled. Two consecutively voided urine specimens were collected by clean-catch midstream urine technique for culture. The urine samples were processed and microbial isolates were identifi ed by conventional methods. Antimicrobial susceptibility testing was performed on all bacterial isolates by Kirby Bauer’s disc diff usion method. Data were analyzed using GraphPad Quick Calcs Statistical Software Inc., USA. Inferential statistics was done by Chi-square (2) test and a P < 0.05 was considered signifi cant. 

Results: The prevalence of ABU in antenatal women was 11.5% (33/287). Lower socio-economic status and low level of education were signifi cant risk factors related to ABU (P=0.02). Parity, maternal and gestational age was not signifi cantly associated with ABU. Escherichia coli (54.5%, 18/33) were the most prevalent isolate followed by Enterococcus faecalis (15.2%, 5/33). Nitrofurantoin was the most eff ective antibiotic, showed resistance rate of 3% (1/33) for both Gram-negative and Gram-positive bacteria.

Conclusion: Routine screening using urine culture method should be performed for ABU in early pregnancy. Specifi c guidelines should be issued and followed for testing antimicrobial susceptibility with safe drugs in antenatal women. Empirical treatment with nitrofurantoin can be recommended, which is a safe drug and active for both Gram-negative and Gram-positive bacteria.

Keywords: Antenatal women, antibiotic resistance, asymptomatic bacteriuria, prevalence, risk factors