Novel variants in CIITA caused type II bare lymphocyte syndrome: A case report.

Background: Type II bare lymphocyte syndrome (BLS II) group A is a rare primary severe immunodeficiency caused by defects in CIITA, one of genes encoding transcriptional regulatory factors for MHC II molecules.

Objective: To report a Chinese boy with mutation of CIITA.

Methods: By reviewing the clinical data of the child and performing a literature search of BLS II group A.

Results: The patient was presented with persistent pneumonia, chronic diarrhea, urinary tract infection, rash, failure to thrive and special facial characteristics. The patient carried novel mutations in CIITA (c.1243delC, p.R415fs*2 and c.3226C>T, p.R1076W) which were identified by next-generation sequencing and confirmed by Sanger sequencing.

Conclusions: This study found novel mutations in the CIITA gene of BLS II, which complemented the mutation spectrum and contributed to the diagnosis, treatment, genetic counseling and prenatal diagnosis of BLS II.