Primary hyperoxaluria type I (PHI) is a cause of
end-stage renal disease in young people. It is caused by deficient activity of hepatic peroxisomal
alanine:glyoxylate aminotransferase (AGT), which results in hyperoxalemia and
hyperoxaluria. The consequent
urolithiasis and
nephrocalcinosis result in renal impairment, with further reduction in
oxalate excretion and eventual systemic
oxalosis. Historically,
renal transplantation has yielded very poor results in these patients because of recurrent
oxalosis of the graft. Within the last 10 years, combined hepatorenal
transplantation has been successfully applied, simultaneously correcting the metabolic lesion in the liver and replacing the damaged kidneys. It has, however, become apparent that medical
therapy with vigorous hydration, inhibitors of stone formation and
pyridoxine (AGT co-factor), may be successful at delaying, and occasionally in preventing,
urolithiasis in some hyperoxaluric patients, particularly those whose
hyperoxaluria is reduced by
pyridoxine. This, together with intensive perioperative management and modern surgical methods of stone management such as
lithotripsy, laser or ultrasound stone fragmentation, and
percutaneous nephrolithotomy, means that
renal transplantation alone may be feasible in selected patients. We describe a patient with PHI with clinical and biochemical evidence of significant residual AGT activity who underwent a successful live-related
renal transplantation with excellent renal function and no stone recurrence 1 year posttransplantation. The appropriate
transplantation strategies for these complex patients are discussed and include isolated
renal transplantation for those patients who are without significant systemic
oxalosis and have evidence of residual AGT activity.