Cernunnos defect in an Iranian patient with T

Defective Cernunnos gene in nonhomologous end-joining (NHEJ) pathway of the DNA repair is responsible for radiosensitive severe combined immunodeficiency (SCID). Herein, presented a new patient with Cernunnos deficiency and summarized the clinical, immunological, and molecular features of reported patients in the literature.The patient was a 6-month-old female born to consanguineous parents. She presented with long-lasting fever, diarrhea, poor feeding, and restlessness. She had suffered from recurrent fever of unknown origin and multiple episodes of oral candidiasis. In the physical examination, microcephaly, failure to thrive, oral candidiasis, pustular rash on fingers, and perianal ulcers, but no dysmorphic feature were observed. The immunologic workup revealed lymphopenia, neutropenia, normocytic anemia, low T- but normal B- and natural killer (NK)- cells, low immunoglobulin (Ig)G, and normal IgA, IgM, and IgE. The T-cell receptor excision circle (TREC) was low and the lymphocyte transformation test (LTT) was abnormal to mitogens and antigens. She was diagnosed with TCernunnos deficiency should be considered as a differential diagnosis in patients with microcephaly, growth retardation, recurrent infections, T-cell defects, and hypogammaglobulinemia. The normal B-cell level in the index patient is an unexpected finding in Cernunnos deficiency which requires further evaluation.