what causes fever?
“Look, my husband has had a fever for two weeks now. One by one tests are done. I still couldn’t find the disease.” This may be an experience for you. Although fever is a common symptom, suffering from fever for a long time without finding a specific cause has taken an important place in medicine.
When a person’s oral temperature is more than 37.60C or rectal temperature is more than 38.0C, it can be said that he is suffering from fever.
Let us first examine how fever occurs.
Fever occurs due to the effect of microorganisms that have entered the body, their toxins and the chemicals released by them, and because some of our body cells work to release components such as cytokines into the blood. These ingredients affect the hypothalamus in our brain, which causes the hormone prostaglandin to be released. This changes the body’s temperature control. Body temperature rises and fever occurs.
Usually the fever symptom subsides in two to three days. But these fevers are sometimes continuous, sometimes showing ups and downs in temperature at different times of the day. Intermittent or persistent fever with no known cause and lasting for more than three weeks is called pyrexia of unknown origin – PUO.
Unexplained fever can be classified into several forms of PUO. The first part is the patients who meet the above definition. The second category is patients who develop fever after hospitalization, but the fever persists for more than three weeks. The third category is patients who have very low blood phagocytic cell counts, but continue to have fever. Having been infected with fever for more than three weeks but belongs to the fourth category. In this way, when the fever lasts for more than three weeks, it is important to pay attention to it because there are many reasons for it.
The main causes of unexplained fever are:-
- Infectious diseases
- Cancer diseases
- Antibodies/immune reactions
- Various other causes
- Mistakes by hospital staff or patient misleading health workers
- Unexplained fever.
There are a number of infectious diseases that cause prolonged fever symptoms. Among these, the presence of pus cysts in the tissues of the abdominal cavity, liver or pelvis is the main one. Intramuscular infections of the heart as well as bone infections or osteomyelitis should be considered here.
In addition, diseases caused by specific pathogens are also responsible for prolonged fever. Tuberculosis, typhoid fever, brucellosis (Brucellosis), rat fever, syphilis are the main bacterial diseases. Epstein Barr (EBV), infectious mononucleosis (IMN), hepatitis and HIV are viruses that cause fever in this way. Fungal diseases like typhus, malaria, amoeba disease and Candida also cause prolonged fever in this way.
Among cancer diseases, lymphoma or lymph node-related cancer, leukemia, liver, pancreas, kidney, and related cancers also cause the symptom of prolonged fever. Diseases like Rheumatoid and certain medications can cause fever symptoms, as well as increased thyroid hormone levels, liver disease, and colon related infections. Incorrect use of the fever needle used to measure fever, errors in the fever needle, as well as some people deceiving health workers by ingesting substances that raise the body temperature, also lead to long-lasting fever.
Thus, when suffering from an unknown disease, it is important to keep the above points in mind and conduct tests. By examining the patient’s medical history, conducting physical examinations, laboratory tests, and systematically observing the temperature changes with a fever chart, the cause of PUO will be revealed. Blood, urine, saliva, cerebrospinal fluid, bone marrow tests, serum tests specific to various pathogens also come to help here.