Diagnóstico diferencial de la fiebre infecciosa prolongada sin focalidad

Persistent fever of unknown origin (PFUO) refers to processes with temperature increases greater than 38.3°C, checked at least twice, over more than 3 weeks' duration, undiagnosed after taking the clinical history, physical examination and the appropriate initial diagnostic tests. Most PFUO are due to infections, neoplasms, inflammatory systemic diseases and a miscellany that includes pharmacological fever and factitious fever, leaving an increasingly reduced group with no identified aetiology. Complementary tests must be guided by a detailed clinical history and thorough physical examination, together with periodic reassessment of the patient. In the event of clinical failure and deterioration, empirical treatments should be used depending on the suspected pathology, although, in general, therapeutic trial is not recommended.