Neutropenia in adults is usually due to either decreased granulocyte production (in the bone marrow) or increased destruction (in the periphery).
Decreased Granulocyte production caused by bone marrow disorders
- Drug-induced neutropenia. Common culprits are antithyroid drugs (e.g. Methimazole), sulfasalazine, Bactrim (trimethoprim-sulfamethoxazole), dipyrone combined with analgesics, clomipramine, and carbimazole.
- Chemotherapy
- Aplastic anemia
- Cyclic neutropenia
- Pure white cell aplasia
- “Chronic benign neutropenia” in African-American and other populations
- Congenital (rare)
Increased destruction caused by peripheral disorders
- Autoimmune disease leading to immune destruction, eg, systemic lupus erythematosus (SLE)
- Hypersplenism
- Sepsis
- Felty’s syndrome (with rheumatoid arthritis and splenomegaly)
- HIV infection
- Acute viral infection
- Large granular lymphocytosis
**One of the first things you must do in a patient with neutropenia is to check medications they are taken, have recently taken and stopped. Make sure you ask for OTC meds and any supplements.