TITLE:
Rate of Asymptomatic Bacteriuria in Pregnancy, Associated Risk Factors, Causative Organisms, Antibiotic Sensitivity Pattern, and Cure Rate among Mothers Attending Antenatal Clinic in Teaching Hospital Peradeniya, Sri Lanka
AUTHORS:
Tharunya Rajayohan, Chaminda Kandauda, Devinda Madugalle, Asanka Tennegedara, Veranja Liyanapathirana
KEYWORDS:
Asymptomatic Bacteriuria, Pregnancy, Antenatal Screening, Antibiotic Sensitivity, Sri Lanka
JOURNAL NAME:
Open Journal of Obstetrics and Gynecology,
Vol.16 No.7,
July
23,
2026
ABSTRACT: Background: Asymptomatic bacteriuria (ABU) in pregnancy can progress to pyelonephritis and adverse maternal and perinatal outcomes if untreated. Contemporary data on ABU burden, risk factors, and antimicrobial susceptibility in Sri Lanka remain scarce. Objectives: To determine the prevalence of ABU in pregnancy, describe associated risk factors, compare urine full report (UFR) against urine culture diagnostically, identify causative organisms and antibiotic sensitivity patterns, and estimate the cure rate following culture-guided treatment. Methods: A longitudinal descriptive study was conducted at the Professorial Unit Antenatal Clinic, Teaching Hospital Peradeniya, Sri Lanka among 411 pregnant women. Midstream clean-catch urine samples were collected for UFR and culture on CLED agar; significant bacteriuria was defined as ≥105 CFU/mL of a single organism. Culture-positive women received seven days of culture-guided antibiotics followed by a test-of-cure culture. Analysis used descriptive statistics, Fisher’s exact test, and chi-square with Monte Carlo p-values (p Results: Among 411 women enrolled, 12 (2.9%; 95% CI: 1.5% - 5.0%) had culture-confirmed ABU. Predominant organisms were Staphylococci (41.7%), Streptococci (33.3%), and Coliforms (25.0%); Group B Streptococcus accounted for 25% of positive cultures. Nitrofurantoin was highly effective against Coliforms and Staphylococci; all Streptococcal isolates were sensitive to ampicillin/amoxicillin. Two-thirds of Coliform isolates showed cephalosporin resistance. UFR pyuria demonstrated 100% sensitivity, 29.2% specificity, and 100% negative predictive value for ABU. Significant associations were identified with current gestational diabetes mellitus (OR = 13.13; p = 0.03), prior ABU history (OR = 53.33; p = 0.04), and significant pyuria (p = 0.04). Among 12 culture-positive women, 9 (75%) completed a test of cure, achieved microbiological cure and three (25%) defaulted follow up. Conclusion: ABU prevalence was relatively low but featured a distinctive pathogen profile with Staphylococcal predominance and notable Group B Streptococcus isolation. Cephalosporin resistance underscores the need for culture-guided treatment and ongoing antimicrobial surveillance. UFR pyuria is a useful screen but cannot replace urine culture as the diagnostic gold standard.