Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 20 6 2021 12 08 693 699 EN Mitra Khalili Department of Radiology, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Hossein Farzi Department of Radiology, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Sepideh Darougar Department of Pediatrics, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran Fatemeh Hajijoo Department of Radiology, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mehrnaz Mesdaghi Department of Immunology, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mahboubeh Mansouri Department of Immunology and Allergy, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Delara Babaie Department of Immunology and Allergy, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Amir Hashemitari East London NHS Foundation Trust, London, United Kingdom Narges Eslami Department of Immunology and Allergy, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran Zahra Chavoshzadeh Pediatric Infections Research Center, Mofid Children’s Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2020 11 09 2021 07 17 Respiratory diseases are considered as significant causes of morbidity and mortality in primary immunodeficiencies. This study aimed to reveal the radiologic patterns of thoracic involvement in these disorders. A total of 58 patients, including 38 cases with combined cellular-humoral and 20 cases with humoral immunodeficiencies, were enrolled in this study. The “combined” group consisted of 12 cases with severe combined immunodeficiency (SCID) and 26 cases with combined immunodeficiency. The “humoral” group included seven patients with Hyper IgM syndrome (HIGMs), seven cases with common variable immunodeficiency (CVID), three patients with X-linked agammaglobulinemia, and three patients with other types of humoral primary immunodeficiencies (PIDs). The mean age of patients at the time of evaluation was 3.3±3.8 and 5.3±3.9 years in combined and humoral groups, respectively. The findings of chest X-rays and CT scans were interpreted and compared. There was a significant difference for alveolar opacification between combined and humoral immunodeficiencies (58% vs. 30%). The bronchopneumonia-like pattern was detected as a significant finding in patients with SCID (42%) and HIGMs (43%). Atrophy of the thymus was detected significantly often in cases of SCID (67%). Two patients with CVID and lipopolysaccharide-responsive and beige-like anchor protein deficiency showed parenchymal changes of granulomatous lymphocytic interstitial lung disease. No significant difference was detected for bronchiectasis, bronchitis/bronchiolitis patterns, pleural effusion, and thoracic lymphadenopathy. Distinct subtypes of primary immunodeficiency may provoke differing and comparable radiological patterns of thoracic involvement; which can clue the clinician and radiologist to the diagnosis of the disease. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/3029 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/3029/1755