Immunology and Host ResponseDiagnosis of Hyper IgM syndrome in a Previously Healthy Adolescent Boy Presented with Cutaneous and Cerebral CryptococcosisAthipongarporn, Athipat MD*; Ittiwut, Chupong PhD†,‡; Manuyakorn, Wiparat MD, PhD§; Assawawiroonhakarn, Surapat MD§; Larbcharoensub, Noppadol MD¶; Shotelersuk, Vorasuk MD†,‡Author Information From the *Department of Pediatrics, Phra Nakhon Si Ayutthaya Hospital, Phra Nakhon Si Ayutthaya †Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University ‡Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society; Departments of §Pediatrics ¶Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. Accepted for publication September 22, 2020. This study was supported by Health System Research Institute and Thailand Research Fund (DPG618000). The authors have no funding or conflicts of interest to disclose. A.A. and C.I. contributed equally to this work. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (www.pidj.com) Address for correspondence: Wiparat Manuyakorn, MD, PhD, Division of Allergy and Immunology, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Rama 6 Rd, Ratchathewi, Bangkok 10400, Thailand. E-mail: [email protected]. The Pediatric Infectious Disease Journal: January 2021 - Volume 40 - Issue 1 - p e18-e20 doi: 10.1097/INF.0000000000002945 Buy SDC Metrics Abstract X-linked hyper IgM (X-HIGM) syndrome is a combined immunodeficiency disease caused by mutations in the CD40LG gene, leading to a defect in immunoglobulin (Ig) class switching recombination and effector T-cell responses. X-HIGM patients usually present in early life with pyogenic bacterial and opportunistic infections. Herein, we report a previously healthy 13-year-old Thai boy who first presented with cutaneous and meningoencephalitis cryptococcosis. Whole-exome sequencing revealed that he was hemizygous for a missense c.514T>C (p.Tyr172His) in CD40LG, confirming a diagnosis of X-HIGM. This report demonstrates that X-HIGM could have an age of onset in teens and systemic cryptococcosis could be its presenting symptoms. Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.