Pyrexia of Unknown Origin

Question 1

Pyrexia is a raised temperature. According to diagnostic criteria, what temperature must the patient have to be diagnosed?

1 - >36.5
2 - >37
3 - >37.5
4 - >38.3

Answer 1

4 - >38.3

Question 2

Pyrexia is a raised temperature >38.3. How long must the fever be present with no confirmed diagnosis to be given the diagnosis of pyrexia of unknown origin?

1 - >48h
2 - >72h
3 - >1 week
4 - >3 weeks

Answer 2

4 - >3 weeks

• patient has no known diagnosis after 1 week of hospital admission

Question 3

All of the following are common causes of Pyrexia of unknown origin. Which is most common?

1 - Infection
2 - Malignancy
3 - Vasculitides/autoimmune disease
4 - Miscellaneous
5 - Undiagnosed

Answer 3

1 - Infection
accounts for 20-40% of cases

• malignancy is a close 2nd accounting for 10-30% if cases

Question 4

Does pyrexia of unknown origin only occur locally?

Answer 4

• no
• it can be local or systemic

Question 5

Which of the following is NOT a cause of a local infection that may lead to pyrexia of unknown origin?

1 - Lungs = pneumonia, MTb
2 - Heart = infective endocarditis
3 - Bone = osteomyelitis
4 - Joints = septic arthritis
5 - Abdomen = pyogenic abscess, hepatitis
6 - CNS = meningitis, encephalitis
7 - Renal = cystitis, pyelonephritis
8 - Skin = cellulitis
9 - Epstein Barr virus infection
10 - Dental = abscess

Answer 5

9 - Epstein Barr virus infection

Question 6

Which of the following is NOT a cause of a systemic infection that may lead to pyrexia of unknown origin?

1 - toxoplasmosis
2 - pneumonia
3 - Epstein Barr virus infection
4 - cytomegalovirus infection
5 - primary HIV infection
6 - brucellosis
7 - lyme disease

Answer 6

2 - pneumonia

Question 7

All of the following are malignancies that have been associated with pyrexia of unknown origin, EXCEPT which one?

1 - Lymphoma
2 - Leukaemia
3 - cardiocyte carcinoma
4 - renal cell carcinoma
5 - hepatocellular carcinoma

Answer 7

3 - cardiocyte carcinoma