Activated PI3K-Delta Syndrome: Pathogenesis, Clinical Manifestations, Diagnosis, Classification, and Management

Document Type : Review


Department of Immunology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran



Activated PI3 kinase delta syndrome (APDS) is a newly recognized primary immunodeficiency that was firstly discovered in 2013. APDS can result from gain-of-function mutations in PI3Kδ catalytic p110δ (PIK3CD known as APDS1) and regulatory p85α (PIK3R1 known as APDS2). Patients with APDS syndrome mostly present some major manifestations such as lymphadenopathy and autoimmune diseases like cytopenia and Immune thrombocytopenic purpura (ITP). Distinguishing APDS from the other antibody deficiencies such as the common variable immunodeficiency (CVID) and hyper IgM disorders is very important to use appropriate and targeted treatment strategies. In this review article, we attempted to discuss the pathogenesis, cell abnormality, clinical manifestations, diagnosis, and treatment of APDS disorder.


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