Fever is a common symptom of many medical conditions:
- Infectious disease, e.g. influenza, common cold, HIV, malaria, infectious mononucleosis, orgastroenteritis
- Various skin inflammations, e.g. boils, pimples, acne, or abscess
- Immunological diseases, e.g. lupus erythematosus, sarcoidosis, inflammatory bowel diseases
- Tissue destruction, which can occur in hemolysis, surgery, infarction, crush syndrome,rhabdomyolysis, cerebral hemorrhage, etc.
- Drug fever
- directly caused by the drug, e.g. lamictal, progesterone, or chemotherapeutics causingtumor necrosis
- as an adverse reaction to drugs, e.g. antibiotics or sulfa drugs.
- after drug discontinuation, e.g. heroin or fentanyl withdrawal
- Reaction to incompatible blood products
- Cancers, most commonly renal cancer and leukemia and lymphomas
- Metabolic disorders, e.g. gout or porphyria
- Thrombo-embolic processes, e.g. pulmonary embolism or deep venous thrombosis
Persistent fever which cannot be explained after repeated routine clinical inquiries, is called fever of unknown origin.