Causes of Neutropenia - Acquired • Infection e.g. hepatitis, sepsis, tuberculosis • Drug and Chemical e.g. chemotherapy, antibiotics, drugs for hypertension • Nutritional deficiency e.g. Vitamin B12, folate, copper • Autoimmune diseases e.g. Lupus, rheumatoid arthritis, Crohn’s disease • Complement activation - Congenital • Kostmann syndrome