title: No evidence of osteopenia 5 to 8 years after ileal orthotopic bladder substitution.
abstract: OBJECTIVE
  The use of bowel segments as bladder substitutes may result in chronic, impaired vitamin D and calcium metabolism, and ultimately in bone demineralization.
  
  
  METHODS
  Bone metabolism was examined in 14 patients who lived for 5 to 8 years with an ileal low pressure bladder substitute after radical cystectomy for bladder cancer. Bone mineral density was measured using dual energy x-ray absorptiometry of the total skeleton, lumbar spine, femoral neck, and tibial epiphysis and diaphysis. Laboratory studies included serum levels of 1,25-dihydroxyvitamin D, 25-hydroxyvitamin D, intact parathyroid hormone, plasma alkaline phosphatase, electrolytes, creatinine and blood gas analysis.
  
  
  RESULTS
  Bone mineral density was normal in all patients. There was no evidence of deficient vitamin D stores. There was a tendency toward slightly elevated serum creatinine values in patients with preexisting impaired renal function, including 1 who also had slight acidosis. No patient had hyperchloremia.
  
  
  CONCLUSIONS
  We found no evidence of osteomalacia, osteoporosis or significant metabolic acidosis in 14 patients with an ileal bladder substitute for 5 to 8 years. However, it is not known whether the absence of osteopenia would also apply to patients with poor renal function, to those not followed meticulously and, thus, at risk for major long-term functional or metabolic disturbances from the ileal bladder substitute or to patients with orthotopic bladder substitutes made from longer or other bowel segments than we used.
mesh_terms: D000138:Acidosis / Q000453:epidemiology / Q000209:etiology; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000378:metabolism; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood; D016022:Case-Control Studies; D003404:Creatinine / Q000097:blood; D015653:Cystectomy; D005500:Follow-Up Studies; D006801:Humans; D007082:Ileum / Q000601:surgery*; D008297:Male; D010281:Parathyroid Hormone / Q000097:blood; D013997:Time Factors; D001749:Urinary Bladder Neoplasms / Q000601:surgery; D016476:Urinary Reservoirs, Continent / Q000009:adverse effects / Q000379:methods
chemical_list: D010281:Parathyroid Hormone; D003404:Creatinine; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002112:Calcifediol; D002118:Calcium