Pyrexia of Unknown Origin Flashcards
1
Q
Define a Fever
A
Body temp over 37C
2
Q
Define a Pyrogen and give an example of each type
A
A substance which cause fever
- Endogenous (cytokines)
- Exogenous (Endotoxins from G-ve bacteria)
3
Q
Definition of pyrexia of unknown origin (PUO)
A
No diagnosis after
- 3 outpatient visits or
- 3 days in hospital or
- 1 week of outpatient investigation
4
Q
4 types of PUO
A
- Classical PUO
- Nosocomial PUO (develops in hospital, undiagnosed after 3 days)
- Neutropenic PUO (undiagnosed fever + NEUTROPHILS <500/mm3)
- HIV-associated PUO (HIV infection fever present and undiagnosed for >3 days for inpatients and >4 days for outpatients)
5
Q
6 initial investigations for PUO
A
- Chest X-Ray
- Urinalysis and urine microscopy
- FBC and differential WBC count
- CRP and ESR
- Blood cultures taken at times of fevers
- Urea, creatinine, electrolytes and LFT’s
6
Q
Indications for further investigation
A
- Tropical Travel (blood for Malarial parasites, HIV)
- New murmur (ECG and Trans-oesophageal echo)
- Headaches (Temporal artery biopsy or CT PET)
- Micro. Haematuria (Auto-antibodies +/- renal biopsy)
- TB contact (Sputum smear, bone marrow, mantoux)
- Drug misuse (screen for blood-borne viruses)
7
Q
Treatment for PUO
A
- Therapeutic trial (rarely used)
Suspected Mycobacterial infection = anti TB therapy
Suspected Vasculitis or Conn. tissue disorder = Steroids
8
Q
Outcome of PUO
A
- Spontaneous resolution more common in the young
- Some patients with no diagnosis respond to NSAID’s or Steroids (steroid responsive PUO)
- Regular re-appraisal required
9
Q
Possible causes of PUO
A
- Infection
- Malignancy
- Inflammatory
