-IBIS-1.5.0-
tx
immune system
fever of unknown origin
diagnoses
definition and etiology
definition: Fever is the dominant sign in a patient's illness but the cause is undetectable. The term usually refers to a rectal temperature greater than or equal to 101.3°F (38.3°C) for at least 2-3 weeks and where the cause cannot be identified after considerable testing.
etiology: In children, infection is responsible for 50% of FUO (viruses in those under 2; endocarditis and mononucleosis over 6); collagen inflammatory disease causes 20% (especially rheumatoid arthritis and inflammatory bowel disease); neoplasms cause 10% (esp. leukemia); miscellaneous accounts for 10% (milk allergy, thyroiditis); and the cause is unidentifiable in approximately 12%. In adults with FUO infection, collagen vascular disease, and neoplasms are most often found; 10% of adults also go undiagnosed.
signs and symptoms
Fever.
Anorexia, weight loss, chills/sweats, fatigue.
Signs and symptoms specific to the underlying cause.
lab findings:
Possibly increased ESR: with collagen diseases or cancer.
Bone marrow examination for leukemia.
Tissue biopsy.
Blood cultures.
Serologic tests.
May see increased or decreased WBC, shift to left, or increased lymphs.
course and prognosis
Course and prognosis relate to the underlying pathology. Total recovery by group is as follows: infection 90%; collagen diseases 10%; cancer, depends on the type and stage of tumor; unidentified 33%.
differential diagnosis
Determine primary cause.
footnotes