Introduction: 1 in nearly 4000 infants are born with Hypoplastic Left Heart Syndrome (HLHS) yearly (1).  Staged reconstructive palliative surgeries are the only viable options for these patients. However, circulatory failure and ischemia often leads to Fontan failure (1). The prevalence of fail Fontan is 26- 30% over 20 years.  Subsequently, long term fontan failure results in liver failure requiring combined heart-liver transplant (CHLTx) for survival. Pediatric CHLTx is rarely performed in the US. In a study conducted in 2020 only 20 patients were identified. Within this institution only 1pediartic and 15 adults have been performed since 2011.  Complications associated with CHLTx included stroke, cirrhotic nodularity and acute kidney injury requiring renal replacement therapy. All patients experienced the latter two (2). 
Case: KS was a 16-year-old female with complex CHD to include heterotaxy, interrupted IVC with azygos continuation, TAPVR to the RA, hypoplastic MV and LV with VSD, with normal cardiac systolic function without significant pulmonary congestion. She ultimately developed Fontan circulation resulting in Fontan associated liver disease. She was listed status 1A for combined heart/liver transplant. On evaluation her renal function was normal as evidence by a BUN/creatinine of 11/0.81 and cystatin C of 0.6 at listing and BUN/ Cr. 12/0.66 on day of surgery. Intraoperatively she developed bleeding and vasoplegia requiring replacement of blood product was placed on CRRT for fluid removal. Post operatively she became hemodynamically unstable secondary to extended ischemic time the donor liver required for en-bloc transplantation. She continued to require CRRT subsequently she was transitioned to single pass hemodialysis. Three months post-transplant, KS continued to have abnormal BUN and creatinine 87/5 and remained anuric. She was referred for kidney transplant evaluation for chronic renal failure and listed for kidney transplant on 4/16/2024, subsequently transplanted on 6/20/2024.  
Summary: KS presented with normal renal function at time of transplantation and acquired acute renal failure immediately post operatively, developing chronic renal failure requiring renal transplantation. No previous patients were reported to have chronic failure leading renal transplantation in recent studies. KS was one of 16 patients requiring CHLTx within this institution and the only one requiring kidney transplant secondary to renal failure post CHLTx.  More research is needed in pediatric patients receiving CHLTx requiring renal transplant.