Autosomal recessive complete interferon- gamma receptor-2 (IFN-γR2) deficiency is a rare potentially fatal primary immune deficiency that predisposes to disseminated mycobacterial disease.Hematopoietic stem cell transplantation (HSCT) is currently the only curative treatment. Few patients had been reported so far.
To report on the outcome of hematopoietic stem cell transplantation (HSCT) in patients with IFNγR2 deficiency transplanted in Sultan Qaboos University Hospital (SQUH), Oman.
A retrospective report that included seven patients with IFNγR2 deficiency from three Omani families. All patients were homozygous for the same mutation (c.-175_+102del) INFGR2. Four patients underwent HLA- matched related donor (MRD) HSCT (3 siblings and 1 parent), while the other 3 received T- cell depleted (TCD) haploidentical HSCT from family donors. The stem cell source was peripheral blood stem cells in five patients and bone marrow in two. Five patients received myeloablative (MAC), and two had reduced intensity conditioning (RIC).
The overall survival rate was 85.7%; while event-free survival was 71.4%. One out of seven patients died on Day+31 with Gram-negative sepsis, while the other six patients were cured from their original disease (median follow up of 78.5 months). One patient had primary graft failure following a TCD-haploidentical transplant and was successfully re-transplanted from another haploidentical relative. Three patients received Donor lymphocyte infusion (DLI) for mixed chimerism.
HSCT is curative for complete IFN-γR2 deficiency. In the current cohort from Oman, 85.7% of our patients have been cured with either a MRD or a TCD haploidentical transplant. Genetic analysis at birth in children of high risk couples permits early diagnosis, prevents the morbidity of BCG vaccination and can enable safer and more successful transplant outcomes.

Copyright © 2021. Published by Elsevier Inc.