Fever, PUO

Question 1

Definition of pyrexia of unknown origin

Answer 1

1. Fever >38.3 on multiiple occaisions
2. > 3 weeks of illness
3. Failure to reach a diagnosis after 1 week of patient investigation

Question 2

Definition of neutropenia PUO

Answer 2

PUO (3 criteria) +

<1 x 10^9 neutrophils

Question 3

Which cancers commonly present with PUO

Answer 3

• lymphoma

- leukaemia

Question 4

Which part of the brain regulates fever

Answer 4

Posterior hypothalamus

Question 5

Describe the pathophysiology of fever

from the prostaglandin to the effects on the body

Answer 5

1. Trigger causes release of PGE2
2. PGE2 acts on hypothalamus, which generates response
3. PERIPHERAL VASOCONSTRICTION
4. Norephinephrine increases THERMOGENESIS in brown adipose tissue
5. Ach stimulates muscle to INCREASE METABOLIC RATE
6. Migration of neutrophils and T cells to combat infection (due to higher temperature)

Question 6

Which part of the brain regulates fever

Answer 6

Posterior hypothalamus

Question 7

Non-infective causes of fever

Answer 7

• Blood transfusion

- Progression of disease

Question 8

What global infection may cause twice daily fever

Answer 8

Leishmaniasis

Question 9

What global infection may cause relapsing remittent fever

Answer 9

• Malaria

- Kawasaki’s disease

Question 10

What global infection may cause saddleback fever (cyclical fever but lower each time)

Answer 10

• Dengue

- Legionare’s

Question 11

What global infection may cause a constant fever with relative bradycardia

Answer 11

Typhoid

Question 12

Which class of drugs may be given as prophylaxis in neutropenic patients

Answer 12

Fluoroquinolones

eg levofloxacin