title: Urinary spot albumin:creatinine ratio for documenting proteinuria in women with preeclampsia.
abstract: OBJECTIVE
  To assess whether a single urinary spot urinary albumin:creatinine ratio (ACR) can be used to estimate 24-hour urinary protein excretion in women with preeclampsia.
  
  
  METHODS
  ACR and 24-hour urinary protein excretion were measured in 50 consecutive patients with preeclampsia. ACR was determined in a spot midstream urine sample and the amount of protein excretion was quantified in a 24-hour urine collection performed the following day. The correlation between the spot ACR and 24-hour urine protein excretion was assessed, and the diagnostic value of ACR was expressed in terms of specificity and sensitivity. Receiver operating characteristic curve analysis was used to determine the best cutoff values of the spot ACR for mild preeclampsia (proteinuria ≥ 0.3 g/24 h) and severe preeclampsia (defined in China as proteinuria ≥ 2 g/24 h).
  
  
  RESULTS
  A strong correlation was evident between the spot ACR and 24-hour urinary protein excretion (r = .938; P < .001). The optimal spot ACR cutoff point was 22.8 mg/mmol for 0.3 g/24 h of protein excretion (mild preeclampsia) with a sensitivity and specificity of 82.4% and 99.4%, respectively, and 155.6 mg/mmol for 2 g/24 h of protein excretion (severe preeclampsia) with a sensitivity and specificity of 90.6% and 99.6%, respectively.
  
  
  CONCLUSIONS
  Compared with 24-hour urinary protein excretion, the spot urinary ACR may be a simple, convenient, and accurate indicator of significant proteinuria in women with preeclampsia.
authors.affiliation: Department of Obstetrics and Gynecology, Nanfang Hospital, Southern Medical University Guangzhou, Guangdong Province, China.
authors.forename: Qitao
authors.initials: Q
authors.lastname: Huang
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Gao
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Yu
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Shuoshi
authors.initials: S
authors.lastname: Wang
authors.forename: Mei
authors.initials: M
authors.lastname: Zhong