Infection

Bacterial

Meningitis, upper/lower respiratory infections (e.g., pneumonia, tuberculosis), endocarditis, cholecystitis, appendicitis, cellulitis, diverticulitis, upper and lower genitourinary infections

Viral

Common cold, HIV, mononucleosis, hepatitis

Fungal, rickettsial, parasitic

Collagen vascular disease

Rheumatoid arthritis, rheumatic fever, lupus, polyarteritis nodosa, sarcoidosis, temporal arteritis, vasculitis

Malignancy

Leukemia, lymphoma, renal cell carcinoma, hepatocellular carcinoma, lung cancer, pancreatic cancer

Medications

Anesthetics, antibiotics, anticholinergics, antipsychotics, lithium, steroids, tricyclic antidepressants, thyroid hormone, alcohol withdrawal

Central nervous system

Head trauma, mass lesions

Cardiovascular

Myocardial infarction, deep venous thrombosis, thrombophlebitis, pulmonary embolism

Gastrointestinal

Hepatitis, inflammatory bowel disease

Endocrine

Acute adrenal insufficiency, gout, thyroid storm, pheochromocytoma

Hyperthermia

Neuroleptic malignant syndrome, heat stroke, anesthetic hyperthermia

Psychiatric

Serotonin syndrome, factitious fever

Miscellaneous

Atelectasis, transfusion reaction, transplant rejection, tissue injury, hematoma, IV lines