Enteric hyperoxaluria secondary to short bowel syndrome as an indication for combined kidney and intestinal transplantation
Laurens J. Ceulemans1, Yannick Nijs1, Frederiek Nuytens1, Kathleen Claes2, Bert Bammens2, Maarten Naesens2, Pieter Evenepoel2, Dirk Kuypers2, Diethard Monbaliu1, Jacques Pirenne1
1Abdominal Transplant Surgery, University Hospitals Leuven, Leuven, Belgium; 2Nephrology and Renal Transplantation, University Hospitals Leuven, Leuven, Belgium
Introduction:
Reports on combined Kidney Transplantation (KTx) and Intestinal Transplantation (ITx) (cKITx) -not as part of a multivisceral graft- are extremely scarce. We report 2 patients primarily referred for KTx because of end-stage renal disease (ESRD) as a consequence of enteric hyperoxaluria (EH) due to short bowel syndrome (SBS).
Case Reports:
Case1:
A 41-year(y)-old female, TPN-dependent after complete small bowel resection due to volvulus, developed oxalate kidney stone formation and ESRD secondary to EH. An entire small bowel and kidney was transplanted (7y-old donor). The postoperative course was uneventful. Due to non compliance, an acute rejection occurred 46 months (mo) post-Tx, which fully responded to steroids. Currently, 6 y post-Tx she is TPN-/dialysis-free and oxalate urinary excretion is normal (32mg/24h; normal:10-41mg/24h).
Case 2:
A 56y-old female, suffering from Crohn, became TPN-dependent after multiple bowel resections and was dialysis-dependent due to ESRD secondary to EH. An entire small bowel and kidney was transplanted (9y-old donor). Currently, 1y 4mo post-Tx, she is TPN-/dialysis-free and recurrence of EH was excluded showing normal urinary excretion (20mg/24h).
Discussion:
Unlike primary hyperoxaluria -due to hepatic enzyme deficiencies, causing an excessive endogenous production of oxalate- the enteric form of hyperoxaluria is secondary to various gastrointestinal diseases (jejuno-ileal resection, inflammatory bowel disease) that lead to an excessive absorption of calcium oxalate. In primary hyperoxaluria, liver transplantation has been performed in addition to KTx to avoid disease recurrence. In contrast, data on KTx for secondary hyperoxaluria are scarce and to our knowledge no case of cKITx for this indication has been reported. Replacing the intestine in addition to the kidney rendered both our patients not only dialysis-/TPN-free, but also prevented EH recurrence.
On the other hand, based on the fact that post-ITx renal failure will increase the mortality risk by a factor >4, we also believe that patients primarily referred for ITx and who have advanced -but not yet terminal- renal failure should be considered for prophylactic combined KTx, in order to avoid post-Tx evolution towards ESRD and the additional mortality risk that this entails.
Conclusions:
Replacing the intestine in addition to the kidney is a valuable treatment option in KTx candidates with EH secondary to SBS. Alternatively, replacing the kidney in addition to the intestine should be performed in ITx candidates with ESRD or prophylactic in those with advanced -but not yet terminal- renal failure to decrease the mortality risk, entailed by post-ITx renal failure.