It is often classified into 3 categories: Classical Cancer-associated Drug-induced Table Disorders and Drugs Associated with Acute Febrile Neutrophilic Dermatosis Classification Disorder / Drug Classical Acute respiratory illness Gastrointestinal infection Inflammatory and autoimmune disorders Pregnancy Cancer-associated Acute myeloid leukemia Myelodysplastic syndromes Drug-induced Granulocyte colony-stimulating factor (G-CSF, the most common drug cause) Antibiotics (such as minocycline and trimethoprim / sulfamethoxazole) Anticancer drugs Antiseizure drugs Others (eg, abacavir, furosemide, hydralazine, nonsteroidal anti-inflammatory drugs, oral contraceptives, retinoids) About 25% of patients have an underlying cancer, 75% of which are hematologic cancers, especially myelodysplastic syndromes and acute myelogenous leukemia.