Infectious Mononucleosis Flashcards
Define Infectious Mononucleosis?
Clinical syndrome caused by primary EBV infection
AKA glandular fever
What type of virus is EBV?
It is a gamma-Herpes virus (dsDNA)
Where is EBV found?
It is found in the pharyngeal sections of infected individuals and is transmitted by close contact (e.g. kissing, sharing eating utensils)
What happens with an EBV infection in the body?
EBV infection of the epithelial cells of the oropharynx leads to B cell infection
The infected B cells disseminate EBV across the body leading to a humoral and cellular immune response
What is a classic feature of Infectious Mononucleosis?
Atypical Lymphocytes in the peripheral blood
What happens with EBV after infection?
It remains latent in lymphocytes
Reactivation may occur following stress or immunosuppression
What is the epidemiology of Infectious Mononucleosis?
COMMON
Two age peaks:
1-6 yrs
14-20 yrs
What is the incubation period of Infectious Mononucleosis?
4-8 weeks
What is the onset of symptoms of Infectious Mononucleosis?
Abrupt
What are the presenting symptoms of Infectious Mononucleosis?
Sore throat Fever Fatigue Headache Malaise Anorexia Sweating Abdominal pain
What are the signs of Infectious Mononucleosis?
PYREXIA Oedema and erythema of the pharynx White/creamy exudate on the tonsils Palatal petechiae Cervical/generalised lymphadenopathy Splenomegaly Hepatomegaly Jaundice (5-10%) Widespread maculopapular rash (in patients who have received ampicillin)
What investigations do you do for Infectious Mononucleosis?
Bloods
Blood Film
Heterophil Antibody Test (aka Monospot Test, Paul Bunnell Test)
Throat Swabs
IgM or IgG to EBV viral capsid antigen
IgG against Epstein-Barr nuclear antigen (EBNA)
What bloods do you do for Infectious Mononucleosis?
FBC - leucocytosis
LFTs - high AST/ALT
What do we see on a Blood Film for Infectious Mononucleosis?
Lymphocytosis with atypical lymphocytes
What is the Heterophil Antibody Test?
Based on EBV antigens being similar to antigens on RBCs of many animals but NOT humans
Mixing blood of an EBV-positive human with animal blood will make the animal’s red cells aggregate and precipitate out of solution
May give false-negatives in the early stages of infection before antibodies are generated
Why do we do Throat Swabs for Infectious Mononucleosis?
Exclude streptococcal tonsillitis
What is the management plan for Infectious Mononucleosis?
Bed rest
Paracetamol and NSAIDs - helps with fever, malaise
Corticosteroids in SEVERE cases
What is the important drug advice you give for Infectious Mononucleosis?
Don’t give Ampicillin or Amoxicillin if Infectious Mononucleosis is suspected - nearly 100% of patients with glandular fever develop a maculopapular rash
What general advice do you give for Infectious Mononucleosis?
Avoid contact sports for 2 weeks (because of risk of rupturing your spleen)
What is the main general complication of Infectious Mononucleosis?
Lethargy for several months
What are the Respiratory complications of Infectious Mononucleosis?
Airway obstruction from oedematous pharynx, secondary bacterial throat infection, pneumonitis
What are the Haematological complications of Infectious Mononucleosis?
Haemolytic or aplastic anaemia
Thrombocytopaenia
What are the GI/Renal complications of Infectious Mononucleosis?
Splenic Rupture Fulminant Hepatitis Pancreatitis Mesenteric adenitis Renal Failure
What are the CNS complications of Infectious Mononucleosis?
Guillain-Barre syndrome
Encephalitis
Viral Meningitis
What are the EBV-associated malignancy related complications for Infectious Mononucleosis?
Burkitt’s Lymphoma (in sub-Saharan Africa)
Nasopharyngeal cancer
Hodgkin’s Lymphoma
What is the prognosis for patients with Infectious Mononucleosis?
Most make uncomplicated recovery (within 3 weeks)
Immunodeficiency and death are VERY RARE
