PEDIATRIC UROLOGY

One hundred percent patient and kidney allograft survival with simultaneous liver and kidney transplantation in infants with primary hyperoxaluria: a single-center experience
Millan MT, Berquist WE, So SK, Sarwal MM, Wayman KI, Cox KL, Filler G, Salvatierra O Jr, Esquivel CO
Stanford University School of Medicine, Palo Alto, CA 94304, USA
Transplantation 2003; 76: 1458-63

• Background: Combined liver-kidney transplantation is the definitive treatment for end-stage renal disease caused by primary hyperoxaluria type I (PH1). The infantile form is characterized by renal failure early in life, advanced systemic oxalosis, and a formidable mortality rate. Although others have reported on overall results of transplantation for PH1 covering a wide age spectrum, none has specifically addressed the high-risk infantile form of the disease.
• Methods: Six infants with PH1 underwent simultaneous liver-kidney transplantation at our center between May 1994 and August 1998. Diagnosis was made at 5.2 +/- 3.3 months of age, they were on dialysis for 11.8 +/- 2.3 months, and they underwent transplantation at 14.8 +/- 3.0 months of age when they weighed 10.6 +/- 1.7 kg.
• Results: At a mean follow-up of 6.4 +/- 1.7 years (range, 3.9 - 8.1 years), we report 100% patient and kidney allograft survival. There were no cases of acute tubular necrosis. Long-term kidney allograft function remained stable in all patients, with serum creatinine values of less than 1.1 mg/dL and a mean creatinine clearance of 99 mL/min/1.73 m2 at follow-up. Those who received combined hemodialysis and peritoneal dialysis pretransplant had lower posttransplant urinary oxalate values than those receiving peritoneal dialysis alone. There was improvement in growth and psychomotor and mental developmental scores after transplantation.
• Conclusions: Combined liver-kidney transplantation for the infantile presentation of PH1 is associated with excellent outcome when the approach includes early diagnosis and early combined transplantation, aggressive pretransplant dialysis, and avoidance of posttransplant renal dysfunction.
  
  
• Editorial Comment
  The authors report their experience with a rare but physiologically important disease. Primary hyperoxaluria is a severe, life-threatening disease that results in systemic oxalosis and early renal failure. Treatment of the neonatal renal failure has involved various regimens of “hyperdialysis” along with renal transplantation, as the total body oxalate stores are so high that immediately after successful renal transplantation, severe hyperoxaluria results. Because the enzyme deficiency responsible for the condition is in the liver primarily, renal transplantation alone does not solve the basic problem long-term. Hence, some have advocated combined liver and kidney transplantation, that, when combined with a regimen of “hyperdialysis” preoperatively should be curative.
  The authors present their experience with 6 cases in which the infants underwent liver-kidney transplant at a mean age of 15 months. All patients have survived with good renal function at a mean follow-up of 6.4 years. Though this approach is still experimental, the authors demonstrate a remarkable result in children who otherwise would have an extremely high mortality.

Dr. Barry A. Kogan
Chief and Professor of Urology and Pediatrics
Albany Medical College
Albany, New York, USA