Bolton, ChrissyPandey, SumeetPagnamenta, Alistair TTaylor, Jenny CTaylor, John MMarsh, Judith C WPotter, VictoriaTravis, SimonUhlig, Holm HBurch, NicolaHarrison, BethMorgan, James2023-07-282023-07-282020-01J Crohns Colitis . 2020 Jan 1;14(1):142-1471876-447910.1093/ecco-jcc/jjz11231157858http://hdl.handle.net/20.500.14200/1438Mendelian disorders in glucose-6-phosphate metabolism can present with inflammatory bowel disease [IBD]. Using whole genome sequencing we identified a homozygous variant in the glucose-6-phosphatase G6PC3 gene [c.911dupC; p.Q305fs*82] in an adult patient with congenital neutropenia, lymphopenia and childhood-onset, therapy-refractory Crohn's disease. Because G6PC3 is expressed in several haematopoietic and non-haematopoietic cells it was unclear whether allogeneic stem cell transplantation [HSCT] would benefit this patient with intestinal inflammation. We show that HSCT resolves G6PC3-associated immunodeficiency and the Crohn's disease phenotype. It illustrates how even in adulthood, next-generation sequencing can have a significant impact on clinical practice and healthcare utilization in patients with immunodeficiency and monogenic IBD.en© European Crohn’s and Colitis Organisation 2019.HaematologyGastroenterologyArticle