Pyrexia/Fever Of Unknown Origin Flashcards
What are the three characteristics of PUO?
Fever>38.3 Celsius on at least 3 occasions
Persisting without diagnosis > 3 weeks
In spite of investigation on at least 3 days (outpatient or admitted)
What are the 4 classifications of PUO?
Classical
Nosocomial
HIV-associated
Neutropaenic
What are the three causes of Classic PUO?
Infection
Malignancy
Collagen vascular disease
What is the difference between patients with classic PUO and Nosocomial PUO?
Nosocomial PUO - fever in patients who have been hospitalised > 24hrs but no fever on admission
How to differentiate patients with neutropenic PUO?
They have neutrophil count <= 500per mm3
What is the difference for HIV associated PUO patients?
Duration of fever must be >4 weeks for outpatients and >3 days for inpatients
HIV infection must be confirmed
What is the percentage of infectious causes of classic PUO?
17-35%
What is the % of non infectious inflammatory causes of classic PUO?
26-36%
What is the % of Neoplastic causes of classic PUO?
10-20%
What is the % of Miscellaneous causes of classic PUO?
3-15%
What is the % of undiagnosed classic PUO?
16-39%
What are some of the BACTERIAL causes of infectious classic PUO?
TB, infective endocarditis (culture neg) osteomyelitis, occult abscess
What are some of the VIRAL causes of infectious classic PUO?
Ebstein-Barr virus
HIV
Cytomegalovirus
What is the common cause for PARASITIC infectious classic PUO?
Malaria
What is the common cause for FUNGAL Infectious classic PUO?
Histoplasmosis
What are non infectious causes of classic PUO?
Giant cell arthritis
Systemic lupus erythematosis
Rheumatoid arthritis
Adult onset stills disease
What are the malignant causes of classic PUO ?
Lymphoma*
Leukaemia
Renal cell carcinoma
Hepatocellular carcinoma
Colon carcinoma
What are some of the miscellaneous causes of classic PUO?
Drugs
Hereditary
Deep vein thrombosis
Inflammatory bowel disease
Kawasakis syndrome
Where are occult abscesses for classic PUO usually located?
Abdomen or pelvis
-they develop secondary to appendicitis or diverticulitis