Name: T-cell immunodeficiency with thymic aplasia | Acronym: TIDTA
Alt. names: Nezelof syndrome

Gene: FOXN1 | MOI: Autosomal recessive | Mechanism of action: Loss of Function

No. of cases in DB: 3 | First reported in: 2019

Last updated on: 2023-04-01 by Xiao P. Peng

OMIM: 242700

Orphanet: 83471

MONDO: -

DOID: -

ClinGen:

Description

To date, thirteen patients from nine families have been described with this condition (PMID: 8911612, 10206641, 20864124, 20978268, 21507891, 25173801, 28636882, 30903456, 35064468). The predominant findings are nail dystrophy, varying degrees of alopecia, thymic aplasia, erythroderma and skin rashes, along with severe T-cell immunodeficiency and recurrent viral, fungal, and opportunistic infections either disseminated or largely involving the sinopulmonary and GI tracts. Some patients also have chronic diarrhea, hepatosplenomegaly and/or lymphadenopathy, structural neurological abnormalities, developmental delays, and failure to thrive. Typically seen laboratory abnormalities include significantly skewed predominance of CD45RO+ memory over CD45RA+ naïve T cell populations and abnormal lymphocyte proliferative responses to mitogen or antigen stimulation, as well as hypogammaglobulinemia, increased IgE levels, eosinophilia, cytopenias, and sometimes reduced B and NK cell counts.

Management

Thymus transplantation has been shown to be curative for this condition, leading to functional T- and B-cell reconstitution (PMID: 20978268). One subject developed autoimmunity after transplantation.