%0 Journal Article %A Mokhantar, Khaoula %A Allaoui, Abir %A Ailal, Fatima %A Bakkouri, Jalila El %A Ouazahrou, Kaoutar %A Errami, Abderrahmane %A Bousfiha, Ahmed Aziz %A Moudatir, Mina %T Classification of common variable immunodeficiency through immunological and clinical phenotyping in Moroccan patients %D 2023 %J Qatar Medical Journal, %V 2023 %N 2 - Second Qatar Allergy Conference %@ 2227-0426 %C 23 %R https://doi.org/10.5339/qmj.2023.sqac.23 %K hypogammaglobulinemia %K B-cell subsets %K common variable immunodeficiency %K flow cytometry %K classification %I Hamad bin Khalifa University Press (HBKU Press), %X Objective: Common variable immunodeficiency (CVID) is a complex inborn error of humoral immunity with complications of both infectious and non-infectious origins. Classifications of CVID patients provide a clearer understanding of the pathogenesis, prediction, and management of non-infectious complications. This study aims to classify Moroccan CVID patients based on the European classification (EUROclass). Materials and Methods: We recruited 20 CVID patients meeting standard diagnostic criteria (5-6). After collecting clinical and demographic data, we used flow cytometry to analyze B-cell subsets and group patients and assess the relation of each group with clinical manifestations. Results: 90% of the patients in our cohort study had a history of respiratory infections. The non-infectious manifestations included splenomegaly, autoimmunity, lymphadenopathy, and granulomatous diseases diagnosed in 50%, 45%, 40%, and 25% of patients, respectively. We observed significant co-occurrence of splenomegaly with autoimmunity and granulomatous diseases to a lesser extent. Patients had a significant reduction in total, switched memory, marginal zone-like, plasma blasts, and a substantial increase in the percentage of activated B cells, suggesting a defect in the late phases of B-cell differentiation. This condition was linked with an increased occurrence of splenomegaly and granulomatous affections. Besides, patients also had an expansion of CD21low B-cells, which was strongly associated with splenomegaly. Conclusion: The classification of the first Moroccan cohort of CVID patients showed agreement with previous results. It suggests the possibility of adopting this approach on a global scale for better diagnosis and follow-up of CVID patients. %U https://www.qscience.com/content/journals/10.5339/qmj.2023.sqac.23