Selective IgA Deficiency By James Fernandez, MD, PhD, Cleveland Clinic Lerner College of Medicine at Case Western Reserve University Reviewed / Revised Jan 2023 View Patient Education Symptoms and Signs Diagnosis Prognosis Treatment Key Points Selective IgA deficiency is an IgA level < 7 mg / dL (< 70 mg / L, < 0.4375 micromol / liter) with normal IgG and IgM levels.