Epstein-Barr Virus, Mumps & HIV Flashcards
What is infectious mononucleosis (IM)?
A viral infection caused by the Epstein-Barr virus (EBV).
Also known as ‘mono’ or ‘glandular fever’.
What triad of features characterises (IM)?
1) fever
2) pharyngitis
3) lymphadenopathy
How is EBV spread?
This virus is found in the saliva of infected individuals.
Infection may be spread by kissing or by sharing cups, toothbrushes and other equipment that transmits saliva.
Typical exam scenario for IM:
An adolescent with a sore throat, who develops an itchy rash after taking amoxicillin.
Mononucleosis causes an intensely itchy maculopapular rash in response to amoxicillin or cefalosporins.
Clinical features of IM?
- Prodromal phase: malaise, fatigue, headache, and low-grade fever
- Classic triad: sore throat, fever, lymphadenopathy
- Splenomegaly (may rarely predispose to splenic rupture)
- Hepatitis: transient rise in ALT
- Palatal petechiae
What is effect of taking amoxicillin whilst having infectious mononucleosis?
Development of a maculopapular, pruritic rash.
Lymphadenopathy in IM vs tonsillitis?
IM - lymphadenopathy may be present in the anterior and posterior triangles of the neck
Tonsillitis - typically only results in the upper anterior cervical chain being enlarged
Prognosis of IM?
Symptoms typically resolve after 2-4 weeks.
In certain diseases (such as HIV) we can test for specific antibodies to infectious mononucleosis.
In IM, what antibodies does the body produce?
Heterophile antibodies (these are more multipurpose and not specific to the EBV antigens).
It takes up to 6 weeks for these antibodies to be produced.
What 2 tests can be used to test for heterophile antibodies?
1) Monospot test
2) Paul-Bunnell test
What is the monospot test?
This introduces the patient’s blood to RBCs from HORSES.
Heterophile antibodies (if present) will react to the horse RBCs and give a positive result.
What is the Paul-Bunnell test?
This is similar to the monospot test but uses red blood cells from sheep.
It is possible to test for specific EBV antibodies in IM.
What do these antibodies target?
Viral capsid antigen (VCA)
IgM vs IgG antibody?
The IgM antibody rises early and suggests acute infection.
The IgG antibody persists after the condition and suggests immunity.
What are patients advised to avoid in EBV?
1) Alcohol - EBV impacts the ability of the liver to process the alcohol.
2) Contact sport - due to the risk of splenic rupture.
Management of IM?
Supportive:
1) Rest during the early stages, drink plenty of fluid, avoid alcohol
2) Simple analgesia for any aches or pains
3) Consensus guidance in the UK is to avoid playing contact sports for 8 weeks after having glandular fever to reduce the risk of splenic rupture
What are some complications of IM?
1) Haemolytic anaemia
2) Thrombocytopenia
3) Splenic rupture
4) Hepatitis
5) Cholestastic hepatitis
6) Chronic fatigue
7) Glomerulonephritis
EBV infection is associated with certain cancers, notably which one?
Burkitt’s lymphoma
What is mumps?
Mumps is an acute viral illness caused by the Paramyxovirus, primarily affecting the salivary glands, particularly the parotid glands.
Which salivary glands does mumps particuarly affect?
Parotid glands
How is mumps transmitted?
Through respiratory droplets and direct contact with infected individuals.
What is the pathognomonic sign of mumps infection?
Swelling of the parotid gland (parotitis) –> presents as tenderness and erythema overlying the angle of the mandible.
Which vaccine protects against mumps?
MMR vaccine offers around 80% protection against mumps.
Presentation of mumps?
- Prodrome: flu-like symptoms e.g. fever, myalgia, lethargy, reduced appetite
- Parotid gland swelling with associated pain: unilateral or bilateral
- Fever
Can present with symptoms of the complications:
- Abdominal pain (pancreatitis)
- Testicular pain and orchitis (orchitis)
- Confusion, neck stiffness & headache (meningitis or encephalitis)
What is the infective period of mumps in relation to parotid swelling?
infective 7 days before and 9 days after parotid swelling starts
What is the incubation period of mumps?
14-21 days