title: Clinical utility of trace proteinuria for microalbuminuria screening in the general population.
abstract: BACKGROUND
  The urine dipstick test that regards > 1+ proteinuria as positive is unsuitable for microalbuminuria screening owing to its low sensitivity in the general population. We conducted a cross-sectional survey to examine whether trace proteinuria could be an indicator of microalbuminuria.
  
  
  METHODS
  The subjects were 2321 participants in a community-based health check-up in Takahata, Japan. Dipstick tests for proteinuria and the urine albumin-creatinine ratio (UACR) measurement were performed with single-spot urine specimens collected early in the morning. The results of the dipstick tests were recorded as (-), trace, (1+), (2+), and (3+). Micro- and macroalbuminuria were defined as UACR 30-300 mg/g and > 300 mg/g, respectively.
  
  
  RESULTS
  Overall, the prevalence and median UACR levels of urine protein (-), trace, (1+), (2+), and (3+) were 92.0% (8.8 mg/g), 3.5% (43 mg/g), 2.6% (81 mg/g), 1.4% (315 mg/g), and 0.5% (1073 mg/g), respectively. Within the trace proteinuria category, the prevalence of microalbuminuria in all subjects, men, subjects >or=60 years, diabetic subjects, and hypertensive subjects was 59.3%, 73.8%, 71.2%, 88.9%, and 68.0%, respectively. By regarding trace proteinuria as positive, the sensitivity of the urine protein dipstick test for micro- and macroalbuminuria was improved (from 23.3% to 37.1%), while its specificity was not significantly changed (from 98.9% to 97.3%).
  
  
  CONCLUSIONS
  Trace proteinuria could be a useful indicator of microalbuminuria in the general population, and especially in subjects at high risk of cardiovascular disease.
authors: Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata 990-9585, Japan. kkonta@med.id.yamagata-u.ac.jp
authors: Tsuneo
authors: T
authors: Konta
authors: Zhimei
authors: Z
authors: Hao
authors: Satoshi
authors: S
authors: Takasaki
authors: Hiroshi
authors: H
authors: Abiko
authors: Mizue
authors: M
authors: Ishikawa
authors: Toshiyuki
authors: T
authors: Takahashi
authors: Ami
authors: A
authors: Ikeda
authors: Kazunobu
authors: K
authors: Ichikawa
authors: Takeo
authors: T
authors: Kato
authors: Sumio
authors: S
authors: Kawata
authors: Isao
authors: I
authors: Kubota
mesh_terms: D000368:Aged; D000419:Albuminuria / Q000175:diagnosis*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011934:Reagent Strips; D016482:Urinalysis
chemical_list: D011934:Reagent Strips