Pyrexia of unknown origin

Question 1

Fever

Answer 1

Elevation above norm
variation upto 0.8C daily
low in morn and high in evening
part of systemic inflammatory response syndrome (SIRS)

Question 2

Pyrogens

Answer 2

substance which causes fever
endogenous-cytokines
exogenous- endotoxins
act at hypothalmic thermoregulatory centre to cause reduce heat loss

Question 3

Initial investigations

Answer 3

Chest xray
urinalysis and urine microscopy
FBC and WCC
C reactive protein(CRP) and erthrocyte sedimentation rate
blood cultures
urea, creatinine, electrolytes, liver function

Question 4

Invasive investigations

Answer 4

tissue for culture and histology
bone marrow and liver examination (malignancy/TB/lymphoma)
laparotomy (rare)

Question 5

No diagnosis treatment

Answer 5

NSAIDs or steroids

Question 6

Causes

Answer 6

infection
malignancy
inflammatory- teporal arteritis, IBD, SLE,vasculitis
hiv
TB- mycobacterium tuberculosis
endocarditis
sarcoidosis
venous thrombosis
drug fevers
no diagnosis

Question 7

Associated w trpical travel

Answer 7

malaria- do bloods

bone marrow for leishmaniasis

Question 8

Mycobacterium TB diagnosis?

Answer 8

Should respond to chemo within 2 weeks

Question 9

Temporal arteritis diagnosis?

Answer 9

Should respond to steroids dramatically within 48 hrs

Question 10

Fabricated fever

Answer 10

Self induced
Self injection common
May continue when sick
Psych
Microbiology strongest clue- multiple diff organisms on blood culture at different times