Introduction: Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a rare congenital disorder with poor prognosis. It is associated with intestinal pseudo-obstruction and urinary system problems secondary to dilated bladder. MMIHS patients usually have multiple surgical interventions related to pseudo-obstruction episodes and become TPN dependent due to surgical or functional short gut syndrome. We aim to analyze patient and graft characteristics including early and late post-transplant complications in patients with MMIHS with visceral transplantation (VT).

Methods: Data of all patients with MMIHS receiving visceral transplantation between 1990 and 2019 were reviewed retrospectively.

Results: Six MMIHS patients underwent VT at our institution. One had prior isolated small bowel transplantation at another facility and had allograft failure. Transplantation was with multivisceral (MVT) in 5 and modified multivisceral (MMVT) in one patient with good liver function. Pancreaticoduodenal and splenic complex was preserved in MMVT. Allograft included colon and pyloromyotomy was performed in last 4 patients. Thymoglobulin was administered as induction agent and tacrolimus and prednisolone were given as maintenance immunosuppression. Median age at transplantation was 4.3 years (range=1-18.6 years) with a M/F ratio of 5/1.Overall patient and graft survival is 100% at median follow-up of 3.8 years (range=1.2-15.4 years). Acute cellular rejection was the most frequent early post-transplant complication (83%) and 2 patients had EBV associated post-transplant lymphoproliferative disorder during the follow up period. One patient needed kidney transplantation because of IgA nephropathy. Two patients currently have end ileostomy and 3 have end colostomy after closure of loop ileostomy. One patient is awaiting ileostomy closure. Five patients have attained nutritional autonomy and were weaned-off TPN and intravenous fluids. One of these 5 patients is on jejunostomy tube feeds due to oral aversion. One patient is still on tube feeds and TPN due to esophageal stricture caused by perforation after myotomy for achalasia diagnosed at post-transplant 8 months.

Conclusions: Visceral transplantation for MMIHS patients is a lifesaving procedure with excellent patient and allograft survival. Timing, thorough pre-transplant work-up and appropriate allograft selection are keys for good outcomes.