Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 22 1 2023 02 20 110 118 EN Zahra Golchehre Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Samin Sharafian Department of Immunology and Allergy, Mofid Children's Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Nader Momtazmanesh Pediatric Congenital Hematologic Disorders Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Zahra Chavoshzadeh Department of Immunology and Allergy, Mofid Children's Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Abdollah Karimi Pediatric Infections Research Center (PIRC), Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Hassan Abolhassani Research Center for Immunodeficiencies, Children's Medical Center Hospital, Tehran University of Medical Sciences, Tehran, Iran AND Division of Clinical Immunology, Department of Biosciences and Nutrition, Karolinska Institute, Huddinge, Sweden Maryam Kazemi Aghdam Pediatric Pathology Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Koroush Vahidshahi Pediatric Cardiology, Shahid Modarres Hospital, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Seyedehatefeh Hashemimoghaddam Department of Immunology and Allergy, Mofid Children's Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Farid Kosari Department of Pathology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Zahra Khafafpour Pediatric Congenital Hematologic Disorders Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Bibi Shahin Shamsian Pediatric Congenital Hematologic Disorders Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mohammad Keramatipour Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 2022 06 16 2022 11 22 CD27 is a costimulatory receptor involved in the maturation of the innate and adaptive immunity. CD27, through interaction with CD70, plays a role in the control of Epstein-Barr virus (EBV) infection. CD27 deficiency leads to an immune dysregulation disease characterized by EBV susceptibility. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) might put patients with primary immunodeficiency at risk for adverse outcomes. Chromogenic in situ hybridization (CISH) study was performed to detect EBV in the lymphoma tissue. Genetic analysis of the patient was done with Whole Exome Sequencing and detected variant was confirmed with PCR-Sanger sequencing. Here we report a 20-month-old boy with CD27 deficiency who developed lymphoma and coronary artery ectasia and had been infected with SARS-CoV-2. Clinical and laboratory findings were incompatible with atypical Kawasaki syndrome or multisystem inflammatory syndrome in children (MIS-C). As CD27 deficiency is a rare immune defect, publishing clinical data about the identified patient(s) can shed light on our knowledge about the related phenotype and the spectrum of clinical manifestations associated with CD27 deficiency. Thus, our findings expanded the spectrum of manifestations beyond EBV infection, highlighting this unusual cardiac sequela that could be related to EBV infection, lymphoma, or an underlying disease.  https://ijaai.tums.ac.ir/index.php/ijaai/article/view/3580 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/3580/1928