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Tetratricopeptide repeat domain 7A (TTC7A) deficiency is a rare autosomal-recessive disorder characterised by intestinal atresia, congenital enteropathy, inflammatory bowel disease, recurrent stricture formation, and variable immunodeficiency. Reported median survival is 8 – 12 months, though outcomes depend on phenotype and access to interventions such as haematopoietic stem cell transplantation (HSCT) and intestinal or multivisceral transplantation. We describe three male infants dependent on parenteral nutrition, with TTC7A-related intestinal failure–associated liver disease, each illustrating distinct disease trajectories (table 1).Case 1 A neonate with postnatal bowel obstruction required resection of 20 cm of atretic terminal ileum, caecum, and ascending colon with end ileostomy formation on day 2 of life. At 18 months, he required gastroduodenotomy for pyloric stricture and mucous fistula formation for multiple colonic atresias and strictures. Subsequently, he developed portal hypertension with portosystemic shunting, and symptomatic stomal varices requiring embolisation, sclerotherapy, and treatment with carvedilol, and eventually transjugular intrahepatic portosystemic shunt (TIPSS). Whilst awaiting assessment for HSCT for well-controlled primary immunodeficiency, he died aged 2 years 3 months from sepsis and multiorgan failure.Case 2 This infant presented at six weeks with vomiting, secretory diarrhoea, and hypoalbuminaemia. Imaging revealed long segments of left colonic narrowing, and at 3.5 years, he underwent a colonoscopy complicated by colonic perforation requiring ileostomy and mucous fistula formation. He had recurrent, paroxysmal microbiology-negative pyrexia, vomiting, and increased stooling, and multiple endoscopies demonstrated variable mucosal inflammation. Symptoms improved with leflunomide and low-dose prednisolone, but were non-responsive to infliximab. At 4 years, he awaits bone marrow transplantation assessment before consideration of a size-matched modified multivisceral transplant with splenic preservation.Case 3: Infant with multiple intestinal atresias requiring three laparotomies within 4 months of life, including pyloroplasty, loop ileostomy, and mucous fistula formation. Due to symptoms of combined immunodeficiency, he had HSCT at 18 months, which was complicated by multiple episodes of sepsis and chronic Epstein-Barr viraemia. He developed evolving hypersplenism with stomal varices, prominent portosystemic collaterals, and chronic symptoms of per rectal bleeding and haematemesis. After initial multidisciplinary transplant discussion, he was listed for multivisceral transplant (liver, stomach, and small bowel), however following subsequent decompensation with episodes of gastrointestinal bleeding requiring TIPSS, pulmonary haemorrhage, and renal failure requiring haemofiltration, the decision was withdrawn.There is no established standard of care for patients with TTC7A deficiency. Surgery for intestinal atresias does not prevent recurrent stricture formation, and intestinal inflammation often remains refractory to immunosuppressive therapy, as demonstrated in all three infants reported. Although HSCT may be considered to correct immunological defects, patients are likely to continue to experience gastrointestinal symptoms without definitive treatment such as intestinal or multivisceral transplantation. Both interventions should be considered in select cases depending on phenotype, although optimal timing and sequence remain unknown.Abstract OC52 Table 1Summary of clinical features of infants with TTC7A deficiency