Overview of Immunodeficiency Disorders By James Fernandez, MD, PhD, Cleveland Clinic Lerner College of Medicine at Case Western Reserve University Reviewed / Revised Jan 2023 View Patient Education Primary Immunodeficiencies Secondary Immunodeficiencies Geriatrics Essentials: Immunodeficiency Key Points Topic Resources Humoral Immunity Deficiencies Cellular Immunity Deficiencies Combined Humoral and Cellular... Phagocytic Cell Defects Complement Deficiencies Some Disorders That Cause... Some Drugs That Cause Immunosuppr... Immunodeficiency disorders are associated with or predispose patients to various complications, including infections, autoimmune disorders, and lymphomas and other cancers.