title: Posterior urethral valves: creatinine velocity, a new early predictor of renal insufficiency.
abstract: OBJECTIVE
  Antenatal screening has led to early detection of posterior urethral valves (PUV). However, despite early intervention, a proportion of children will develop chronic renal insufficiency. We studied the trend of serum creatinine following urinary tract decompression during the neonatal period in infants as a possible predictor of chronic renal insufficiency.
  
  
  METHODS
  Patients treated by endoscopic resection of posterior urethral valves between 1993 and 2004 were identified. From these, infants treated within the first 30 days of life were identified. Serum creatinine values taken within the first 5 days following initial drainage were recorded. A creatinine velocity for each patient was calculated by linear regression analysis. Creatinine was considered rising if velocity was >3 μmol/L/day, or falling if velocity was <-3 μmol/L/day. Chronic renal insufficiency was defined as CKD2 or higher.
  
  
  RESULTS
  Sixty-four neonates had decompression of the urinary tract. Of these, 16 had rising creatinine despite drainage, 10 had a plateau in creatinine level, and 36 had falling creatinine following drainage. Insufficient data were available in two to calculate creatinine velocity. Progression to renal insufficiency was significantly higher in patients with an initial rise in creatinine (62.5%) than in those with plateau creatinine (40%) or falling creatinine (8.6%) (P ≤ 0.0005 by Fisher exact test). Mean follow-up was 9.2 years.
  
  
  CONCLUSIONS
  Rising creatinine, even transiently, following urinary tract drainage in neonates with posterior urethral valves is significant and is a new and important indicator of long-term prognosis.
authors: Urology Department, Birmingham Children's Hospital, Birmingham, West Midlands B4 6NH, UK. robcole900@gmail.com
authors: Robert
authors: R
authors: Coleman
authors: Thomas
authors: T
authors: King
authors: Cezar-Doru
authors: CD
authors: Nicoara
authors: Muhammad
authors: M
authors: Bader
authors: Harish
authors: H
authors: Chandran
authors: Andrew
authors: A
authors: Robb
authors: Karan
authors: K
authors: Parashar
mesh_terms: D003404:Creatinine / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology*; D014521:Urethra / Q000002:abnormalities* / Q000601:surgery*
chemical_list: D003404:Creatinine