Infectious mononucleosis (I) Flashcards
What is infectious mononucleosis also known as? (3)
- glandular fever
- mono
- kissing disease
What is infectious mononucleosis caused by?
Epstein-Barr virus (EBV) infection in 80-90% of cases
(Other causes are much less common and result in a diagnosis of mononucleosis syndrome rather than infectious mononucleosis)
How is infectious mononucleosis spread?
Highly contagious and spreads via bodily secretions especially saliva (hence ‘kissing disease’)
What is peak incidence for infectious mononucleosis?
15-24 year olds
How long is the incubation period of infectious mononucleosis?
6 weeks
How long are symptoms of infectious mononucleosis shown for in adults vs children?
- 2-4 weeks in adults
- asymptomatic in children
- often subclinical in young children
What is the classic triad of infectious mononucleosis?
Fever, pharyngitis and lymphadenopathy (along with atypical lymphocytosis)
What are the clinical features of infectious mononucleosis? (8)
- fever
- pharyngitis (exudative or non-exudative)
- lymphadenopathy (cervical or generalised - tender, non-erythematous and discrete nodes)
- malaise
- splenomegaly
- rash
- erythematous
- maculopapular - 99% of patients who take ampicillin/amoxicillin while they have mono
- morbilliform
- signs of hepatitis (hepatomegaly, jaundice)
- myalgia
When does maculopapular rash develop in infectious mononucleosis?
99% of patients who take ampicillin/amoxicillin while they have mono
What might you see on examination of a patient with infectious mononucleosis? (2)
- petechiae on soft palate
- splenomegaly
What are the risk factors for infectious mononucleosis? (2)
- kissing
- sexual behaviour
What are the first-line investigations for infectious mononucleosis? (4)
- FBC
- heterophile antibodies AKA Monospot test (non-specific)
- EBV-specific antibodies (high sensitivity and specificity)
- LFTs
What would you see on FBC for infectious mononucleosis?
- lymphocytosis
- atypical lymphocytosis
- neutropenia
What would you see on LFTs for infectious mononucleosis?
Elevated - raised AST and ALT by 2-3x
What would heterophile and EBV-specific antibodies show for infectious mononucleosis?
- positive heterophile antibodies
- positive for EBV-specific antibodies: VCA-IgM, VCA-IgG, EA, EBV, EBNA
- IgG to EBV nuclear antigens appears 6-12 weeks after infection and are lifelong
What imaging can be considered for infectious mononucleosis and what would you see?
- ultrasonography of abdomen - splenomegaly
- CT of abdomen - splenic rupture
What would a blood film for infectious mononucleosis show?
Atypical lymphocytes
What are some differential diagnoses for infectious mononucleosis?
- group A streptococcal pharyngitis - do throat culture
- hepatitis A
- acute HIV infection
- adenovirus - coryza, cough, pneumonia, conjunctivitis, diarrhoea
- HSV-6
- CMV infection
- HSV-1: exudative pharyngitis, gingivostomatitis, odynophagia
- influenza - no lymphadenopathy
What does treatment for infectious mononucleosis mainly focus on?
Symptomatic
What is the 1st line treatment for infectious mononucleosis?
Supportive care:
- rest
- fluids
- avoid alcohol
- avoid physical activity for 4 weeks due to risk of splenic rupture
- analgesics/antipyretics - paracetamol or ibuprofen
- corticosteroids (prednisolone) in severe cases
What is the 1st line treatment for infectious mononucleosis with upper airway obstruction or haemolytic anaemia?
Supportive care + corticosteroid (prednisolone)
What is the 1st line treatment for infectious mononucleosis with thrombocytopenia?
Supportive care + corticosteroids or IV immunoglobulin
What are some complications of infectious mononucleosis?
- antibiotic-induced rash (maculopapular rash)
- chronic fatigue
- splenic rupture
- neurological complication
- chronic disease
- renal complications
Describe the prognosis of infectious mononucleosis.
- very good for healthy people
- death occurs rarely and is caused by airway obstruction, splenic rupture, neurological complications, haemorrhage or secondary infection
