Infective Mononucleosis

Question 1

What is infective mononucleosis caused by.

Answer 1

Caused by Epstein-Barr virus (EBV).

Question 2

How is EBV transmitted. (3)

Answer 2

Salivary secretions.
Blood transfusions.
Bone marrow transplant.

Question 3

What are the symptoms of infective mononucleosis. (5)

Answer 3

Fever. 
Fatigue. 
Malaise. 
Anorexia. 
Myalgia.

Question 4

What are the physical signs of infective mononucleosis. (5)

Answer 4

Papular rash. 
Pharyngitis. 
Palatal petechiae. 
Lymphadenopathy (especially posterior triangle of the neck). 
Splenomegaly.

Question 5

What is seen in the blood results of a patient with infective mononucleosis. (3)

Answer 5

Raised WCC (lymphocytosis).
Low platelets.
Raised LFTs.

Question 6

What special tests is done in infective mononucleosis.

Answer 6

Paul Bunnell test.

Question 7

What are the complications of infective mononucleosis infections. (15)

Answer 7

Bacterial superinfection. 
Haemolytic anaemia. 
Splenic rupture. 
Myocarditis. 
Pericarditis. 
Cerebellitis. 
Myelorediculitis. 
Cranial nerve lesion. 
Fulminant hepatitis. 
Respiratory distress syndrome. 
Severe thrombocytopenia/aplastic anaemia. 
Acute renal failure. 
Meningitis. 
Encephalitis. 
Guillain-Barre syndrome.

Question 8

What other conditions has EBV been associated with in immunosuppressed patients. (5)

Answer 8

Burkitt's lymphoma. 
Nasopharyngeal carcinoma. 
Hodgkin's disease. 
Leiomyosarcoma.
Oral hairy leucoplakia (in AIDS patients).

Question 9

What percentage of the population will develop an EBV infection at some point in their lives.

Answer 9

90%.

Question 10

What is the incubation period for EBV.

Answer 10

4-5weeks.

Question 11

What sort of virus is EBV.

Answer 11

DNA herpesvirus with a predeliction for B lymphocytes.

Question 12

What does EBV cause. (2)

Answer 12

Proliferation of T cells. (which are cytotoxic to EBV cells).
These latter cells then become immortalized, and can proliferate (rarely) in a way indistinguishable from immunoblastic lymphoma in immunodeficient individuals).

Question 13

What is seen on a blood film of EBV infection. (2)

Answer 13

Lymphocytosis. 
Atypical phagocytes (large, irregular nuclei).

Question 14

What is the differential diagnosis for these blood film results:
Lymphocytosis.
Atypical phagocytes. (7)

Answer 14

Viral infections (CMV, HIV, parvovirus, dengue). 
Toxoplasmosis. 
Typhus. 
Leukaemia. 
Lymphoma. 
Drugs. 
Lead poisoning.

Question 15

What are the cardinal signs of infective mononucleosis. (4)

Answer 15

Lymphocytosis.
Fever.
Cervical lymphademopathy.
Pharyngitis.

Question 16

What are some causes of infective mononucleosis. (5)

Answer 16

EBV. 
Cytomeglavirus. 
HHV-6 or 7.
HIV-1 primary infection. 
Toxopasmosis.