Management of oxalosis

Oxalosis is the final stage of primary hyperoxaluria type I (PHI) when reduction of GFR produces oxalate accumulation. It involves bones, arteries, eyes, heart, nerves, etc. The management of oxalosis starts with prevention of nephrocalcinosis and renal failure by diluting urine and by inhibiting oxalate crystal formation either by increasing the urinary citrate or the urinary pyrophosphate. At endstage renal disease (ESRD) there is no dialysis modality for avoiding the progression of oxalosis. Combined liver/kidney transplantation (LKT) represents the most effective approach. The European PHI transplant registry recently reported 64 LKT with a five-year patient survival of 80% and progressive healing of oxalosis. Four children who received LKT in our unit are reported, all of whom are alive with a follow-up of three months to five years. Bone disease completely healed in one case after three years, but retinal deposits persisted despite improvement of visual acuity. A special perioperative protocol must be applied for protecting the graft from oxalate released from the stores. Laboratory follow-up including oxalemia and urinary crystal volume helps to adjust the individual prescriptions. This intensive management must be continued as long as oxalate stores persist.