title: Prediction of pre-eclampsia in early pregnancy by estimating the spot urinary albumin: creatinine ratio using high-performance liquid chromatography.
abstract: OBJECTIVE
  To establish whether a spot urinary albumin: creatinine ratio (ACR) measured before 20 weeks of gestation can predict subsequent pre-eclampsia when urinary albumin is measured by high-performance liquid chromatography (HPLC).
  
  
  METHODS
  Prospective exploratory study.
  
  
  METHODS
  Antenatal clinic in a tertiary teaching hospital, Victoria, Australia.
  
  
  METHODS
  A cohort of 265 women with a singleton pregnancy, normal renal function, and no evident proteinuria, attending antenatal clinics between 12 and 20 weeks of gestation.
  
  
  METHODS
  The ACR was determined from a mid-stream urine (MSU) sample taken between 17 and 20 weeks of gestation. Intact urinary albumin was determined by HPLC; creatinine was measured by modified Jaffe's method.
  
  
  METHODS
  Pre-eclampsia (primary); gestational hypertension, small for gestational age (SGA), gestational diabetes mellitus, gestational age at delivery, and prematurity (secondary).
  
  
  RESULTS
  The median ACR was 28 mg/mmol (IQR 16-46 mg/mmol). Women who subsequently developed pre-eclampsia had a significantly higher ACR (median 50 mg/mmol; IQR 33-90 mg/mmol) compared with women suffering from gestational hypertension (median 27 mg/mmol; IQR 8-35 mg/mmol), and compared with unaffected women (median 28 mg/mmol; IQR 16-46 mg/mmol). Mothers of SGA infants also had a significantly higher median ACR. By ROC analysis, the optimum ACR to predict pre-eclampsia was 35.5 mg/mmol: the relative risk of developing pre-eclampsia in women with a urinary ACR ≥ 35.5 mg/mmol was 7.8 times more than in those with a urinary ACR < 35.5 mg/mmol.
  
  
  CONCLUSIONS
  When urinary albumin is measured by HPLC, spot urinary ACR values are higher in early uncomplicated pregnancy compared with previously reported conventional methods. When measured early in the second trimester, an ACR ≥ 35.5 mg/mmol predicted pre-eclampsia well before the onset of clinical manifestations.
authors.affiliation: Department of Renal Medicine, Monash University, Box Hill, Victoria, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Baweja
authors.forename: A
authors.initials: A
authors.lastname: Kent
authors.forename: R
authors.initials: R
authors.lastname: Masterson
authors.forename: S
authors.initials: S
authors.lastname: Roberts
authors.forename: L P
authors.initials: LP
authors.lastname: McMahon
mesh_terms: D000328:Adult; D000419:Albuminuria / Q000175:diagnosis*; D002851:Chromatography, High Pressure Liquid; D003404:Creatinine / Q000652:urine*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007236:Infant, Small for Gestational Age; D011225:Pre-Eclampsia / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D003404:Creatinine