(994) Prevalence and Screening Methods for Asymptomatic Bacteriuria in Pregnancy in Low Resource Settings

Objective: Screening for asymptomatic bacteriuria (AB) has been recommended to reduce the risk of pregnancy complications. The evidence for this practice is outdated and of low quality, and global implementation is inconsistent. We conducted a prospective study in a rural Bangladeshi population to ascertain the prevalence of AB, assess the utility of point of care screening methods, determine antimicrobial sensitivity patterns, and report the prevalence of low birth weight (LBW) in pregnancies with AB.

Study Design: We obtained urine samples from 600 asymptomatic pregnant women (1150 samples) being enrolled in a prospective registry of women in antenatal care. Samples were cultured on blood and MacConkey agar plates. AB was defined as presence of a single organism ≥105 CFU/mL. Antimicrobial sensitivity testing was performed. Samples were inoculated on urine dipslides and analyzed for nitrite and leukocyte esterase (LE) using urine dipsticks (positive dipstick = presence of both nitrite and LE). The performance of dipslide and dipstick were calculated using culture as the reference.

Results: A positive culture was found in 37/1150 samples (3.2%); the overall prevalence of AB during pregnancy was 5.2% (31/600 subjects positive on at least one sample). E. coli was most common (65% of total) followed by Enterococcus and Enterobacter. 90% of all isolates were sensitive to nitrofurantoin, including 100% of E. coli (Table). When compared to culture, the sensitivity of dipslide and dipstick for AB were 65% and 14%. 26% of pregnancies with AB resulted in a LBW newborn vs 21% of pregnancies with negative culture (p=0.56).

Conclusion: AB was present in 1 in 20 pregnant subjects in this cohort. The sensitivity of dipstick and dipslide were poor, indicating lack of suitability to serve as a primary method of screening for AB in this population. Future trials assessing the impact of screening and treating AB in pregnancy on the incidence of adverse outcomes in low resource settings must address logistics and cost of widespread implementation of urine culture capacity given the low sensitivity of point of care screening tests.