Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 56 12 2019 01 22 Adenoid Hyperplasia in a Patient With a Rare Type of Hyper Immunoglobulin M Syndrome Due to CD40 Deficiency 811 814 EN Ahmad Bahrami Division of Allergy and Immunology, Ali-Asghar Hospital, Iran University of Medical Sciences, Tehran, Iran. Zahra Soltani Division of Allergy and Immunology, Ali-Asghar Hospital, Iran University of Medical Sciences, Tehran, Iran. Mohammad Reza Fazlollahi Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran. Farzaneh Rahmani Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. AND Network of Immunology in Infections, Malignancy, and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, Iran. AND NeuroImaging Network (NIN), Universal Scientific Education and Research Network (USERN), Tehran, Iran. Massoud Houshmand Department of Medical Genetics, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran. Marzieh Mazinani Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran. Nima Rezaei Research Center for Immunodeficiencies, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran. AND Network of Immunology in Infections, Malignancy, and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, Iran. AND Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 2018 05 11 2018 06 08 CD40 deficiency yield to an autosomal recessive subtype of hyper-immunoglobulin M syndrome (HGIM type 3), presenting with an almost identical clinical picture to X-linked CD40L deficiency (HIGM type 1) with profound T-cell dysfunction yielding to opportunistic infections as well as neutropenia, autoimmunity, and malignancy. We presented a girl with recurrent upper respiratory tract infections and lymphoid hyperplasia which was diagnosed with type 3 hyper IgM syndrome due to CD40 gene mutation. Otitis media with opportunistic germs and no evidence for an X-linked pattern of inheritance were diagnostic keys to type 3 hyper IgM syndrome in our patient. https://acta.tums.ac.ir/index.php/acta/article/view/7252 https://acta.tums.ac.ir/index.php/acta/article/download/7252/5201