Infectious Mononucleosis (EBV)

EBV is commonly present in:
- Throat washings of patients with infectious mononucleosis, for up to 18 months post-infection.
- Throat washings of 10–20% of healthy adults, indicating asymptomatic carriage.
Transmission is primarily via salivary contact, including:
- Kissing
- Sharing food or drinks
Only a minority of patients report known exposure to an infected individual.

Fever
- Typically highest in the first week
- Resolves within 10–14 days
Sore throat
Generalised lymphadenopathy
- Posterior cervical nodes commonly involved in EBV
  - In contrast, streptococcal pharyngitis usually affects tender submandibular nodes

Palatal petechiae (at the junction of the hard and soft palate)
→ Present in 25–60% of cases
Periorbital oedema
Maculopapular rash
- Seen in up to 90% of patients given amoxicillin or ampicillin

Tonsillar hypertrophy
→ May lead to upper airway obstruction
Splenic rupture
- Risk due to splenomegaly
- Avoid contact sports and careful with abdominal palpation for at least the first 3 weeks or until resolution
Fulminant liver failure
→ Rare
Autoimmune haemolytic anaemia
Haemophagocytic syndrome (HPS)
- Severe systemic EBV disease with liver/renal dysfunction and cytopaenias
- Diagnosis often requires tissue biopsy
Myocarditis
Guillain–Barré syndrome (GBS)

Sequela/Association	Key Facts	Level of Risk / Incidence
Prolonged post-infectious fatigue	Up to 10 % symptomatic ≥ 6 months; majority recover within 2 yrs.	Moderate
– myalgic encephalomyelitis (ME) – chronic fatigue syndrome (CFS) after mono	~10 % meet ME/CFS criteria at 6 months in prospective cohorts.	Low-moderate
Chronic active EBV disease (CAEBV)	Clonal proliferation of EBV-infected T/NK cells → fever, hepatosplenomegaly, cytopenias; curative Rx = allogeneic HSCT.	Very rare (< 1 per 10 6)
Malignancies	Burkitt & Hodgkin lymphoma, NK/T-cell lymphoma, nasopharyngeal carcinoma, EBV-positive gastric carcinoma, post-transplant lymphoproliferative disorder (PTLD). EBV drives ≈ 2 % of all cancers globally.	Small absolute risk but ↑ with immunosuppression
Autoimmune disease links	Molecular mimicry & epigenetic re-programming (EBNA2/EBNA1). Strongest evidence for multiple sclerosis (32-fold ↑ after EBV seroconversion), SLE, RA, Sjögren, T1DM.	Relative risk ↑; absolute risk low
Neurodegeneration	Emerging data on Alzheimer’s disease risk; mechanisms under investigation (B-cell infection, 14-3-3 proteins).	Uncertain
Persistent viral shedding & reactivation	Asymptomatic or symptomatic reactivation in stress / immunosuppression; may precipitate PTLD or autoimmune flares.	Common shedding; clinically significant events rare

EBV-specific serology is the main diagnostic tool:
- Anti-VCA IgM
  - Appears early in infection
  - Persists for several months
  - Most reliable marker of acute infection
- Anti-VCA IgG
  - Appears early
  - May persist long-term
  - Not reliable for distinguishing recent infection
- Anti-EBNA IgG (Epstein–Barr nuclear antigen)
  - Appears 3–4 weeks after infection
  - Once present, persist for life
  - Helpful in diagnosing past or resolving infection

Supportive care is the mainstay of treatment.
- Reassure: most patients convalesce uneventfully; advise graded return to activity.
- Monitor those with fatigue > 6 months for ME/CFS; early multidisciplinary management.
- Warn about red-flag symptoms years later (B symptoms, lymph node enlargement, neuro signs).
Avoid corticosteroids unless clinically indicated
- Corticosteroids are immunosuppressive
- EBV is associated with Oncogenic potential → implicated in Hodgkin lymphoma, nasopharyngeal carcinoma, PTLD
- → may promote EBV-driven B-cell proliferation or malignancy
Therefore, routine corticosteroid use is avoided in uncomplicated cases

Indication	Rationale
Severe upper airway obstruction	Due to massive tonsillar/pharyngeal oedema threatening airway
Acute autoimmune haemolytic anaemia	Immune-mediated RBC destruction; steroids reduce autoantibody activity
Severe thrombocytopenia	Risk of bleeding; likely immune thrombocytopenic purpura (ITP-like)
Severe cardiac or neurologic disease	e.g., myocarditis, encephalitis; life-threatening complications

EBV infectious mononucleosis is a common illness in adolescents and young adults.
Most recover spontaneously within weeks.
Severe or complicated cases may require hospitalisation.
No role for antiviral therapy in uncomplicated cases.
Corticosteroids are reserved for specific severe complications only.