Common causes

• Infection
  • Bacterial, viral, rickettsial, fungal, parasitic
  • CNS, sinuses, dental, endocarditis, pneumonia, liver, biliary system, gastrointestinal, peritonitis, abdominal abscess, urinary tract infection, prostate, sexually transmitted disease, skin, soft tissues, bone, joints
• Autoimmune disease
• CNS disease including head trauma, mass lesion
• Malignancy, especially lymphoma, leukemia, renal cell carcinoma, primary or metastatic liver cancer

Less common causes

• Cardiovascular disease, eg, myocardial infarction, thrombophlebitis, pulmonary embolism
• Gastrointestinal disease, eg, inflammatory bowel disease, alcoholic hepatitis, granulomatous hepatitis
• Miscellaneous, eg, drug fever, sarcoidosis, familial Mediterranean fever, tissue injury, hematoma, factitious fever

Hyperthermia

• Heat stroke, neuroleptic malignant syndrome, malignant hyperthermia

• Fever of unknown origin
• FUO in HIV/AIDS
• Hyperthermia
• Nosocomial fever
• Fever in returning traveler
• IVDU and fever
• Relapsing or recurrent fever
• Postoperative fever
• Fever in immunocompromised
• Postpartum fever