Human body temperature normally follows a rhythm, being lower in the morning and higher in the afternoon. An unusual increase in body temperature is called hyperthermia or fever. Fever in a person with cancer may be a sign of a serious infection and should be reported to the doctor immediately. This brief summary describes fever, its causes, and its treatment. An abnormal increase in body temperature is called fever.
Fever occurs due to a failure in the body's heat regulating system.
Fever is most likely to harm the elderly or the very young. In the elderly, the body's heat regulating system may not work as well, which may cause an irregular heartbeat, poor blood flow, mental changes, or heart failure. Children between the ages of 6 months and 6 years may have a seizure due to a fever. In patients who have had neutropenia for a long time, nearly two-thirds of the cases of fever are caused by infection. Fever can be uncomfortable for patients and may be followed by chills and sweats as the body tries to control its temperature.