Case#:1/M. 1.5 y.o. (onset) and 14 y.o. (at assessment), male

DiseaseAssertion: Patient had arthritis, neutropenia and thrombocytopenia, lymphadenopathy, and abdominal pain. The diagnosis of CTLA4 haploinsufficiency was made retrospectively in 7 patients who underwent HSCT for life-threatening, treatment-resistant immune dysregulation and in 1 patient prospectively (unclear which patients were identified retrospectively and prospectively).

FamilyInfo: Father was noted to have Immune dysregulation, Cytopenias and Lymphoma. The patient's father was also noted to have a complex autoimmune disease and died after autologous HSCT for non-Hodgkin lymphoma.

CasePresentingHPOs: HP:0001369 (Arthritis), HP:0001875 (Neutropenia), HP:0001873 (Thrombocytopenia), HP:0002716 (Lymphadenopathy), HP:0002027 (Abdominal pain), HP:0002720 (Decreased circulating IgA level).

CaseHPOFreeText: Autoimmune pancytopenia, Recurrent abdominal pain, Arthritis

This patient was offered HSCT because of ongoing autoimmunity and risk of lymphoma because his father had complex autoimmune disease and died after autologous HSCT for non-Hodgkin lymphoma.

All 8 patients received steroids and a calcineurin inhibitor before transplant

Five patients (including this patient) had peripheral blood HSC grafts and received cyclosporine and mycophenolate mofetil (MMF) for graft versus host disease (GvHD) prophylaxis.

Patient had cytomegalovirus reactivation early post-HSCT and autoimmune hemolytic anemia 6 months post-HSCT, which responded to steroids; he is now off all medication.

CaseNotHPOs: N/A

CaseNotHPOFreeText: Patient has low levels of IgA but IgG and IgM levels appear to be within normal range. See Table I.

CasePreviousTesting: Not found

GenotypingMethod: Not found

PreviouslyPublished: Yes, Schwab et al. PMID: 29729943

Variant: c.518G>A, p.G173E

ClinVarID: N/A

CAID: CA350138990

gnomAD: Not found

SupplementalData: More information regarding Lymphocyte subsets and Immunoglobulins in Table I. Table II contains variant information and Table III contains further details about HSCT and a breakdown of each patient's transplant procedure.

Note: No mention of whether or not the patient was tested using transendocytosis.