title: Acute pyelonephritis in pregnancy.
abstract: OBJECTIVE
  To examine the incidence of pyelonephritis and the incidence of risk factors, microbial pathogens, and obstetric complications in women with acute antepartum pyelonephritis.
  
  
  METHODS
  For 2 years, information on pregnant women with acute pyelonephritis was collected in a longitudinal study. All women were admitted to the hospital and treated with intravenous antimicrobial agents. We compared the pregnancy outcomes of these women with those of the general obstetric population received at our hospital during the same time period.
  
  
  RESULTS
  Four hundred forty cases of acute antepartum pyelonephritis were identified during the study period (incidence 1.4%). Although there were no significant differences in ethnicity, pyelonephritis was associated with nulliparity (44% versus 37%, P = .003) and young age (P = .003). Thirteen percent of the women had a known risk factor for pyelonephritis. Acute pyelonephritis occurred more often in the second trimester (53%), and the predominant uropathogens were Escherichia coli (70%) and gram-positive organisms, including group B beta Streptococcus (10%). Complications included anemia (23%), septicemia (17%), transient renal dysfunction (2%), and pulmonary insufficiency (7%).
  
  
  CONCLUSIONS
  The incidence of pyelonephritis has remained low in the era of routine prenatal screening for asymptomatic bacteriuria. First-trimester pyelonephritis accounts for over 1 in 5 antepartum cases. Gram-positive uropathogens are found more commonly as pregnancy progresses. Maternal complications continue, but poor obstetrical outcomes are rare.
authors.affiliation: Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390-9032, USA.
authors.forename: James B
authors.initials: JB
authors.lastname: Hill
authors.forename: Jeanne S
authors.initials: JS
authors.lastname: Sheffield
authors.forename: Donald D
authors.initials: DD
authors.lastname: McIntire
authors.forename: George D
authors.initials: GD
authors.lastname: Wendel
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D015994:Incidence; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology / Q000628:therapy; D011704:Pyelonephritis / Q000453:epidemiology / Q000209:etiology / Q000382:microbiology / Q000628:therapy; D012307:Risk Factors