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).Design Prospective exploratory study.Setting Antenatal clinic in a tertiary teaching hospital, Victoria, Australia.Population 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.Outcome measures 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.

The 46^th International Congress of Pathophysiology of Pregnancy and the 35^th Meeting of Japan Society for the Study of Hypertension in Pregnancy

“…We and others have shown both intact and nonimmune albumin excretion is altered in pre-eclampsia and the proportion of albumin fragments in the urine is reduced. 14,15) This is in keeping with long held concepts that pre-eclampsia is associated with both altered glomerular and tubular functions. In the future we may move from measuring proteinuria to measuring podocytes in the urine as an early diagnostic marker of pre-eclampsia.…”

Microalbuminuria as a Predictor of Pregnancy Induced Hypertension

“…17 Another study from Africa revealed that a single sample of urine for microalbuminuria at booking shows good prediction for the subsequent development of preeclampsia or eclampsia. There was increase in incidence of preeclampsia with increasing levels of proteinuria.…”

“…18 These studies showed that proteinuria in early trimester were a predictor of development of pregnancy induced hypertension on follow up. 14,17,18 Additionally we tried to look for the maternal and fetal outcome in patients. Patients with microalbuminuria KDG VLJQL¿FDQWO\ PRUH PDWHUQDO DQG IHWDO FRPSOLFDWLRQV and the APGAR score in this group of patients was low as compared to patients who were negative for microalbuminuria.…”

Is the First Urinary Albumin Creatinine Ratio (ACR) in Women With Suspected Preeclampsia a Prognostic Factor for Maternal and Neonatal Adverse Outcome? A Retrospective Cohort Study

“…As well as being useful in the diagnosis of preeclampsia (4,6), ACR has potential to be useful in predicting adverse pregnancy outcomes (7,8). New prognostic factors are needed in this area (9)(10)(11)(12).…”