Pyrexia of Unknown Origin Flashcards
Define Fever
Elevation of body temperature above normal (37C), Variation of up to 0.8C daily, part of systemic inflammatory response sydrome
What are pyrogens?
substances which cause fever
Endogenous - cytokines
Exogenous - endotoxins from G-ve bacteria
They act as a hypothalamic thermoregulatory centre to cause reduced heat loss and hence fever
What is the Petersdorf and Beeson definition of pyrexia of unknown origin?
Temperature of over 38.3C, recorded on multiple occasions and present for at least 3 weeks. Diagnosis after one week of hospital evaluation
What is nosocomial pyrexia of unknown origin?
Develops in hospital and is diagnosed after 3 days
What is neutropenic PUO?
Undiagnosed fever in patient with neutrophils <500/mm^3
What is HIV-associated PUO?
Fever in a patient with HIV infection present and undiagnosed for more than three days in an inpatient/ four weeks in an outpatient
How do you assess PUO?
History - in depth
Examination - thorough including skin, eyes, mouth, nails and lymph nodes. REPEAT IT
What investigations should be done if PUO is suspected ?
CXR, Urinalysis and Urine Microscopy, FBC, WCC, CRP and ESR, Blood Cultures, Urea, Creatinine, Electrolytes and LFT’s
What should be done if tropical travel seems to be the cause?
Blood for malarial parasites, dengue, HIV, bone marrow
What should be done if a new murmur is suspected?
ECHO
What should be done if the patient is experiencing headaches?
Temporal artery biopsy
What tests should be done if patient is experiencing micro haematuria?
Auto-antibodies and renal biopsy, ultrasound
What should be done if TB is suspected?
Sputum smear, bone marrow, mantoux test
What should be done if drug misuse is suspected?
Screen for blood-borne viruses
What is the treatment for PUO?
Therapeutic trial, anti TB therapy (if TB suspected, steroids (vasculitis or connective tissue disorder)
