STAT3 proteins are critical transcription factors which regulates transcription of the genes that play roles in prolifration, apoptosis, differentiation, inflammation and
survival. STAT3 genes can be affected by mutations related to the both Los of Function (LOS) and Gain of Function (GOF). STAT3 GOF have a wide range of phenotype consisting of recurrent infection, lymphoprolifration, autoimmunity, short stature and malignancy.
In this article we describe an 8 years old patient which his first presentation was an autoimmune anemia at age 3. he was referred to our immunolgy office at age 5 with previous history of hyper reactive airway disease, coombs positive autoimmune hemolytic anemia, refractory seizure, Pneumocystis Carinii Pnemonia (PCP) infection, recurrent sinopulmonary infections and otitis media, intermittent fever and neutropenia.His immunologic evaluation showed inadequate increase in IgG level despite of receiving IVIG due to hemolytic anemia, low levels of IgA and IgE and normal level of IgM wich were suggestive Hyper IgM Syndrome (HIGM). at age 8 his biopsy of mediastinum showed large B-cell lymphoma (CD20 positive).furthur evaluations showed decreased level of CD4 T cells in peripheral blood flow cytometry with decreased antibody titers to tetanus toxin.
Patient was referred to our office, he provided us with his dossier wich is involving all his ducuments since he was only 3 years old.
Screening of primary immunodeficiency related genes showed Somatic STAT3 GOF mutation.what is patricular is mutation was found within somatic cells.
Contrary to our patient,all cases which were reported in three previous studies carried germline STAT3 GOF mutation.