What is fever without symptoms?
Fever occurs when the immune system is working harder. This is usually the case when the body wants to protect itself against pathogens. However, fever can also be caused in very stressful phases of life, for example when the immune system is working harder due to increased cortisol secretion.
However, if the fever occurs repeatedly over a longer period of time without further symptoms, a diagnostic clarification should be carried out, as serious diseases can also be causative. If the cause of the fever cannot be found, it is called a fever of unknown origin. The duration of the fever can often provide information about the underlying cause.
What cause can fever without symptoms have?
Possible causes are always viral or bacterial infections, autoimmune diseases and cancer. The HIV status is always in need of clarification if fever is detected without further symptoms. Diseases that are sometimes difficult to diagnose can initially only be accompanied by the symptom fever.
These include, for example, accumulations of pus (abscesses) in organs or an inflammation of the bone marrow (osteomyelitis). M. Still – a subtype of rheumatoid arthritis – can be accompanied by recurrent fever without any further symptoms. Sarcoidosis, a disease that can affect the lungs, skin and joints, can also only be noticed through high fever.
Furthermore, if the fever persists for a long time, possible causes such as malignant lymphomas and leukemia should be considered. In some cases, repeated fevers are caused by pulmonary embolisms, which do not become symptomatic in any other way. Drugs can also trigger high fever, which is then called drug fever. Among the drugs that can cause fever are cytostatics and antibiotics. Various hereditary fever syndromes can also cause fever without further symptoms.
How do you find out the cause of the fever?
It is important to consult a doctor if fever persists for a long time. Those affected should also check whether other symptoms, such as abdominal pain or joint problems, have occurred recently, even independently of the fever. Initially, the focus is on the survey to find out possible causes.
This is followed by a physical examination, whereby particular attention is paid to swollen lymph nodes or an enlarged liver. A blood sample is also important, which can provide information about infections or disorders in the formation of red and white blood cells. The blood should also be tested for HIV (see: HIV test).
An X-ray of the lungs should be taken to detect certain diseases – for example sarcoidosis. In some cases it may be necessary to take a sample from the bone marrow. This is called bone marrow puncture and is performed, for example, if leukemia is suspected. In addition, further instrumental examinations such as ultrasound, MRT or CT can be used to find a diagnosis. Another procedure that can be used to visualize both infections and cancers is the so-called positron emission tomography (PET).
