Prevalence of Placental Bed Bacterial Infections Among Preterm Births at Kenyatta National Hospital

Abstract

Introduction: Major cause of cause of death globally in children below the age of 5 years is attributed to prematurity. Intrauterine infection during pregnancy contributes significantly to preterm labor, PPROM and finally preterm birth. Approximately 40% cases of spontaneous preterm labor and birth are attributed to infections. The bacteria infecting the placental bed thus have the potential of causing adverse pregnancy outcomes like preterm premature rupture of membranes, chorioamnionitis, preterm labor and birth with resultant neonatal morbidity and mortality. Study Objective: To determine the prevalence of bacterial infections at the placental bed in patients with preterm births at KNH through placental bed bacterial culture and histopathology. Methodology: It was a descriptive cross-sectional study, that involved 116 pregnant women who presented for delivery between 28 and 37weeks‟ gestation at KNH obstetric unit. Informed consent was obtained. Pretested questionnaire was used to collect demographic and obstetric data. Immediately upon delivery, the placenta was placed in a sterilized container and refrigerated at a temperature of 2-8 0C at KNH Morgue. Using CHAMPS protocol for minimally invasive tissue sampling (MITS) Standard Operating Procedure (SOP) protocol v1.1 November 2017, placental cuts were made within 24 hours of specimen collection and submitted to microbiology laboratory for culture and sensitivity analysis. The rest of the placenta was fixed in 10% formalin, standard cuts made into cassettes and submitted to histology laboratory where they were processed into slides. Histological diagnosis was then made using Amsterdam Criteria. Results: From a sample of 116 placentas, the prevalence of placental bed bacterial infection was found to be 47.4%. The most commonly isolated microbes include E.coli(27.3%), Staphylococcus haemolyticus(7.3%),Klebsiella pneumonia(10.9%), Enterococcus faecalis(9.1%) and Acinetobacter baumanni(7.3%). Nitrofurantoin and ciprofloxacin were the most sensitive antibiotics. Histological chorioamnionitis was present in 40.5% of placentas. However, it was found in 40% of placentas that also had positive bacteria culture compared to 41% of placentas that had negative bacteria culture and was negative in 60% of placentas that had positive bacteria culture. There was absent bacterial culture growth and histological chorioamnionitis in 59% of the placentas. Other histological profiles identified include maternal vascular malperfusion, funisitis, fetal vascular malperfusion, Chorangiosis, fetal thrombotic vasculopathy and delayed villous maturation. Conclusion and Recommendations: There is need to update our guidelines to culture sensitive antimicrobials for treatment of patients presenting with preterm labor and PPROM. Molecular techniques of microbe isolation are recommended to supplement culture.