Inflammatory bowel disease and T cell lymphopenia in G6PC3 deficiency

J Clin Immunol. 2013 Apr;33(3):520-5. doi: 10.1007/s10875-012-9833-6. Epub 2012 Nov 20.


Purpose: G6PC3 deficiency presents as a complex and heterogeneous syndrome that classically associates severe congenital neutropenia with cardiac and urogenital developmental defects. Here we investigate the findings of T cell lymphopenia and inflammatory bowel disease in a child with G6PC3 deficiency due to compound heterozygous mutations in intron 3 (c.IVS3-1 G>A) and exon 6 (c.G778G/C; p.Gly260/Arg).

Methods: Histological examination was conducted on all biopsy specimens. Immunophenotyping and lymphocyte proliferation assays were performed. Immunoglobulin levels and vaccine responses were measured.

Results: The patient showed persistent global T cell lymphopenia, with only 8 to 13 % of thymic naive CD31(+)CD45RA(+) cells among CD4 T cells (normal range 27-60 %). Proliferation assays and vaccine responses were within normal limits. The gastrointestinal inflammatory lesions were very closely related to those of glycogen storage disease type 1b, with a Crohn's-like appearance but without granuloma or increased cryptic abscesses. The gastrointestinal disease responded to infliximab therapy. These findings were associated with a polyclonal hypergammaglobuliemia G.

Conclusion: G6PC3 deficiency may present with inflammatory bowel disease and T cell lymphopenia. The diagnosis should thus be considered in a patient with chronic congenital neutropenia and gastrointestinal symptoms. Patients with confirmed disease should also undergo T cell phenotyping to rule out cellular immunodeficiency.

MeSH terms

  • Adolescent
  • Child
  • Gastric Mucosa / pathology
  • Glucose-6-Phosphatase / genetics*
  • Glucose-6-Phosphatase / immunology
  • Humans
  • Inflammatory Bowel Diseases / complications*
  • Inflammatory Bowel Diseases / genetics*
  • Inflammatory Bowel Diseases / immunology
  • Intestinal Mucosa / pathology
  • Lymphocyte Count
  • Lymphopenia / complications*
  • Lymphopenia / genetics*
  • Lymphopenia / immunology
  • Mutation


  • Glucose-6-Phosphatase
  • G6PC3 protein, human

Supplementary concepts

  • T-Lymphocytopenia