Acute pyelonephritis in pregnancy: an 18-year retrospective analysis

• Published in: American journal of obstetrics and gynecology Vol. 210; no. 3; pp. 219.e1 - 219.e6
• Main Authors: Wing, Deborah Ann, MD, Fassett, Michael John, MD, Getahun, Darios, MD, PhD
• Format: Journal Article
• Language: English
• Published: United States Mosby, Inc 01.03.2014
• Subjects: Acute Disease; Adolescent; Adult; Age Factors; California - epidemiology; Female; Humans; Incidence; Obstetrics and Gynecology; perinatal outcomes; Pregnancy; Pregnancy Complications - diagnosis; Pregnancy Complications - epidemiology; Pregnancy Outcome; preterm labor; pyelonephritis; Pyelonephritis - diagnosis; Pyelonephritis - epidemiology; Retrospective Studies; Risk Factors; California; preterm labor; pyelonephritis; perinatal outcomes; pregnancy
• ISSN: 0002-9378; 1097-6868
• DOI: 10.1016/j.ajog.2013.10.006

Objective We sought to describe the incidence of acute pyelonephritis in pregnancy, and to assess its association with perinatal outcomes in an integrated health care system. Study Design A retrospective cohort study was performed using medical records on 546,092 singleton pregnancies delivered in all Kaiser Permanente Southern California hospitals from 1993 through 2010. These medical records include the perinatal service system along with inpatient and outpatient encounter files. Adjusted odd ratios (ORs) and 95% confidence intervals (CIs) were used to estimate associations. Results The incidence of acute antepartum pyelonephritis was 0.5% (2894/543,430). Women with pyelonephritis in pregnancy were more likely to be black or Hispanic, young, less educated, nulliparous, initiate prenatal care late, and smoke during pregnancy. Pregnancies of women with pyelonephritis compared to those without were more likely to be complicated by anemia (26.3% vs 11.4%; OR, 2.6; 95% CI, 2.4–2.9), septicemia (1.9% vs 0.03%; OR, 56.5; 95% CI, 41.3–77.4), acute pulmonary insufficiency (0.5% vs 0.04%; OR, 12.5; 95% CI, 7.2–21.6), acute renal dysfunction (0.4% vs 0.03%; OR, 16.5; 95% CI, 8.8–30.7), and spontaneous preterm birth (10.3% vs 7.9%; OR, 1.3; 95% CI, 1.2–1.5). Most of the preterm births occurred between 33-36 weeks (9.1%). Conclusion We characterize the incidence of pyelonephritis in an integrated health care system where routine prenatal screening for asymptomatic bacteriuria is employed. Maternal complications are commonly encountered and the risk of preterm birth is higher than the baseline obstetric population.