Fever of unknown origin

Called fever of unknown origin, fever of unknown origin (English fever of unknown origin ( FUO ), Latin febris e causa ignota ( febris ECI) ), is the name for a measured at different times body temperature greater than 38.3 ° C over a period of more than three weeks without at multiple medical diagnosis, the cause could be determined.

The diagnosis of fever of unknown origin is not an independent disease, but rather a limited diagnostic possibilities provided by " embarrassment diagnosis". FUO is - as fever generally - a symptom of many different diseases. In most cases are diagnosed in the further course of the underlying disease, fever.

Definition

Originally fever of unknown origin in 1961 by Robert G. Petersdorf and Paul B. Beeson - the fever of unexplained origin also influenced the Anglo-Saxon term - defined as follows:

• The patient is at least three weeks sick.
• The fever was several times higher than 38.3 ° C. at this time
• Despite intensive investigation in -patient stay of one week not the fever -causing disease can be diagnosed.

30 years after this definition, the third criterion of fever of unknown origin was launched in 1991 by DT Durack and AC Street redefined by now sufficient a three-day inpatient hospital stay or three outpatient visits.

In addition, they took it before a division into four classes, which is still valid:

The classic fever of unknown origin can in turn be divided into five categories. In infections, cancers, autoimmune diseases, manipulation ( sham fever, drug fever), and unexplained causes.

Autoimmune diseases are more recent studies have shown that the most common cause of fever of unknown origin. These include connective tissue diseases, vasculitis and granulomatous diseases. Cancers are also a very common cause of fever of unknown origin.

Diagnosis

Fever of unknown origin can be easily determined from the definition by repeated measurement of the body temperature above the minimum three-week period. However, fever is only a symptom of a disease and the primary target of FUO is to identify the underlying disease fever diagnosis in order to initiate appropriate therapy. However, there are currently no guidelines to determine the cause of FUO evidence- based to diagnose. A detailed medical, clinical examination and laboratory diagnosis are the basis for all further investigations.

A helpful, but also very time-consuming, method of diagnosis is positron emission tomography with fluorodeoxyglucose (FDG -PET). This bildgebendem method allows both cancers, as well as inflammation and infection locate.

Therapy

Unless the cause of the fever was identified and the patient is not acutely ill, therapeutic measures are largely meaningless. Nonspecific treatment measures have little use and are for the diagnosis usually more of a hindrance.

Forecast

The cause of FUO are very complex nature. According strongly depends on the prognosis of the disease causing the fever. If after more than six months, no disease is diagnosed, the prognosis is generally good.