Unknown origin fevers, also known as fever of unknown origin (FUO), refers to a medical condition characterized by persistent or recurrent fever without an identifiable cause. The term "unknown origin" implies that the underlying cause of the fever remains undetermined despite extensive medical investigations.
FUO is typically defined as a fever that lasts for more than three weeks with an onset that is not apparent even after one week of investigations in the hospital. It is a diagnostic challenge for healthcare professionals as it can be caused by a wide range of potential factors, including infections, autoimmune disorders, malignancies, and various other inflammatory or metabolic conditions.
Diagnosing the cause of FUO requires a thorough medical history, physical examination, and diligent laboratory and radiological investigations. Blood tests, imaging studies, and sometimes invasive procedures (such as biopsies) may be necessary to determine the source of the fever. However, despite these efforts, approximately 30% of FUO cases remain unresolved.
The management of unknown origin fevers typically involves treating the symptoms and trying to identify and treat any underlying conditions if they become evident. This may involve the use of antipyretic medications to lower the fever, supportive care to alleviate symptoms, and empirical treatments to address potential causes. Additionally, a multidisciplinary approach, involving specialists from different medical fields, may be required to thoroughly evaluate and manage the patient.
