title: Early changes of oxalate and calcium urine excretion in those with calcium oxalate stone formation after extracorporeal shock wave lithotripsy.
abstract: OBJECTIVE
  To determine the extent of transient changes of tubular function in idiopathic calcium-oxalate (CaOx) stone-bearing patients after extracorporeal shock wave lithotripsy (ESWL), calcium and oxalate excretion were measured before and after ESWL.
  
  
  METHODS
  In 22 patients with renal CaOx stones, the plasma values and urine excretion of creatinine, calcium, oxalate, magnesium, and citrate were measured before and on days 1 and 2 after ESWL under conditions of a standardized diet. Overnight urine collection for an 8-hour period was used to measure the urine excretion, and the values were extrapolated to a 24-hour period. For calculation of the urine ion activity, the AP(CaOx) index EQ(s) and the CaOx risk index were used.
  
  
  RESULTS
  After ESWL, hyperoxaluria was noted in 10 patients compared with 2 before ESWL. Hypercalciuria was seen in 11 patients after ESWL compared with 3 before. Combined hyperoxaluria and hypercalciuria was found in 7 patients after ESWL compared with 1 before. Both the oxalate/creatinine and calcium/creatinine ratios were significantly increased after ESWL. The AP(CaOx) index EQ(s) and the CaOx risk index were significantly increased after ESWL in patients with increased post-ESWL calcium and/or oxalate excretion.
  
  
  CONCLUSIONS
  Increased calcium and/or oxalate excretion can be seen in patients with CaOx stones early after ESWL. This increased excretion of lithogenic substances represents an increased risk of fragment apposition after ESWL for the group with a significantly increased AP(CaOx) index EQ(s) and CaOx risk index. Therefore, prophylactic measures in patients at risk early after ESWL might be warranted to prevent possible recurrent stone formation.
authors.affiliation: Department of Urology, Technical University Dresden, Dresden, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Oehlschläger
authors.forename: S
authors.initials: S
authors.lastname: Albrecht
authors.forename: O W
authors.initials: OW
authors.lastname: Hakenberg
authors.forename: S
authors.initials: S
authors.lastname: Schrödter
authors.forename: M
authors.initials: M
authors.lastname: Froehner
authors.forename: A
authors.initials: A
authors.lastname: Manseck
authors.forename: M P
authors.initials: MP
authors.lastname: Wirth
mesh_terms: D000328:Adult; D000368:Aged; D002118:Calcium / Q000097:blood / Q000652:urine*; D002129:Calcium Oxalate / Q000032:analysis; D002951:Citrates / Q000097:blood / Q000652:urine; D003404:Creatinine / Q000097:blood / Q000652:urine; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000737:chemistry / Q000378:metabolism* / Q000628:therapy; D007684:Kidney Tubules / Q000378:metabolism; D008096:Lithotripsy; D008274:Magnesium / Q000097:blood / Q000652:urine; D008297:Male; D008875:Middle Aged; D010070:Oxalates / Q000097:blood / Q000652:urine*; D011446:Prospective Studies; D012008:Recurrence; D012306:Risk
chemical_list: D002951:Citrates; D010070:Oxalates; D002129:Calcium Oxalate; D003404:Creatinine; D008274:Magnesium; D002118:Calcium