title: Persistent asymptomatic isolated hematuria in children: clinical and histopathological features and prognosis.
abstract: BACKGROUND
  This study involving 351 children who had undergone kidney biopsy secondary to persistent asymptomatic isolated hematuria was undertaken to assess histological diagnosis of the disease and its natural history and prognosis.
  
  
  METHODS
  The patients were divided into two groups: 215 patients with asymptomatic isolated microhematuria (AIMH; proteinuria <0.1 g/day) and 136 patients with persistent asymptomatic microhematuria, recurrent macrohematuria and/or proteinuria (AMHP; proteinuria 0.1-0.25 g/day). After kidney biopsy, the patients were monitored for 2-10 years.
  
  
  RESULTS
  Normal biopsies or minor abnormalities were more frequent in AIMH patients than those in AMHP patients, who exhibited IgA nephropathy more frequently. During the 2- to 10-year follow-up period, adverse renal events (i.e., development of proteinuria, hypertension, or impaired renal function) were observed in 13/215 (6.0%) patients with AIMH and 31/136 (22.8%) patients with AMHP (χ(2)=15.521, P<0.001).
  
  
  CONCLUSIONS
  Normal biopsies or minor abnormalities were more frequently observed in AIMH patients, whereas IgA nephropathy and adverse renal events were more frequent in AMHP. Microscopic hematuria, especially when accompanied by macroscopic hematuria and proteinuria, may represent an important risk factor for the development of chronic kidney disease.
authors.affiliation: Department of Nephrology, Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
authors.forename: Chun-Yue
authors.initials: CY
authors.lastname: Feng
authors.forename: Yong-Hui
authors.initials: YH
authors.lastname: Xia
authors.forename: Wen-Jin
authors.initials: WJ
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Xia
authors.forename: Hai-Dong
authors.initials: HD
authors.lastname: Fu
authors.forename: Xia
authors.initials: X
authors.lastname: Wang
authors.forename: Hui-Jun
authors.initials: HJ
authors.lastname: Shen
authors.forename: Gu-Ling
authors.initials: GL
authors.lastname: Qian
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Liu
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Mao
mesh_terms: D000293:Adolescent; D058070:Asymptomatic Diseases; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D005260:Female; D006417:Hematuria / Q000473:pathology*; D006801:Humans; D008297:Male; D011379:Prognosis