What are the clinical manifestations of Epstein-Barr virus infection?

Clinical Manifestations of Epstein-Barr Virus Infection

EBV infection presents most commonly as infectious mononucleosis in primary infection, characterized by fever, lymphadenopathy, pharyngotonsillitis, and hepatosplenomegaly, while chronic or reactivated infections manifest with diverse and potentially severe complications including lymphoproliferative disorders and multi-organ involvement. 1, 2

Primary EBV Infection (Infectious Mononucleosis)

Primary EBV infection typically presents as infectious mononucleosis with a characteristic clinical picture 3:

Classic Triad and Core Symptoms

• Fever occurs in 93.3% of cases 2
• Cervical lymphadenitis presents in 93.0% of patients 2
• Pharyngotonsillitis affects 66.0% of cases 2
• Hepatomegaly is found in 76.2% of patients 2
• Splenomegaly occurs in 63.9% of cases 2
• Periorbital edema appears in 51.5% of patients 2

Additional Features

• Prolonged incubation period of approximately 6 weeks, unusually long compared to most acute viral illnesses 3
• Debilitating fatigue that can persist for weeks to months 1
• Sore throat with lymph node tenderness and pain 1
• Headache, myalgia, and arthralgia are common constitutional symptoms 1

Acute Complications of Primary Infection

Multiple organ systems can be affected during primary EBV infection 1, 4:

System-Specific Complications

• Digestive tract complications: 68.8% of primary infections 2
• Respiratory complications: 18.1% of cases, including upper airway obstruction 2, 4
• Cardiovascular complications: 8.0% of patients 2
• Hematological complications: 2.9% of cases 2
• Neurological complications: 0.8% of primary infections, including meningoencephalitis 2, 5
• Multiple serous effusions: 2.3% of cases 2

Specific Acute Syndromes

• Gianotti-Crosti syndrome (papulovesicular acrodermatitis) 6
• Hemophagocytic syndrome in primary infection 6
• Fulminant hepatitis in atypical presentations 5

Chronic Active EBV Infection (CAEBV)

CAEBV represents a severe form with distinct clinical features 1:

Defining Clinical Characteristics

• Persistent or intermittent fever lasting months 1
• Massive lymphadenopathy that is chronic rather than self-limited 1
• Interstitial pneumonitis in severe cases 1
• Thrombocytopenia associated with poor prognosis 1
• Polyclonal hypergammaglobulinemia 1

Cardiovascular Manifestations (Critical Pitfall)

• Coronary aneurysms are of particular concern in CAEBV patients 1
• Valvular disease can develop during chronic infection 1

Cutaneous Manifestations

• Hypersensitivity to mosquito bites is characteristic and may indicate granular lymphocyte proliferative disorder 1
• Hydroa vacciniforme-like eruptions associated with T-cell or NK-cell lymphoproliferative disorders 1, 6

Reactivated EBV Infection

Reactivation presents differently from primary infection with more complex manifestations 2:

Clinical Presentation Patterns

• Infectious mononucleosis-like disease: 65.0% of reactivations 2
• Hemophagocytic syndrome: 22.6% of cases 2
• Chronic active EBV infection: 5.3% of reactivations 2
• Lymphoma: 3.5% of cases 2

Symptom Frequency in Reactivation

• Fever: 84.0% (lower than primary infection) 2
• Cervical lymphadenitis: 46.9% (significantly lower than primary) 2
• Periorbital edema: 15.4% (much less common) 2
• Pharyngotonsillitis: 18.5% (markedly reduced) 2
• Hepatomegaly: 18.5% (substantially lower) 2
• Splenomegaly: 43.3% (moderately reduced) 2

Complications in Reactivation (Higher Risk)

• Hematological complications: 38.9% (dramatically higher than primary infection) 2
• Multiple serous effusions: 19.0% (much higher than primary) 2
• Neurological complications: 8.0% (significantly increased) 2
• Cardiovascular complications: 14.1% (increased risk) 2
• Multi-systemic damage is more common in reactivation 2

Risk Factors for Reactivation

• Immunocompromised status: 9.3% of reactivation cases occur in long-term immunocompromised patients 2

EBV-Associated Malignancies

EBV is etiologically linked to several malignancies 1:

Lymphoproliferative Disorders

• T-cell or NK-cell lymphoproliferative disorders/lymphomas develop during CAEBV course 1
• Burkitt lymphoma (endemic form) 1
• Hodgkin lymphoma 6, 7
• Plasmablastic lymphoma 6
• Post-transplant lymphoproliferative disorders in immunosuppressed patients 6, 8

Epithelial Malignancies

• Nasopharyngeal carcinoma (undifferentiated type) 1, 7

Other Associated Conditions

• Oral hairy leukoplakia in HIV-positive patients 5, 6
• Kikuchi histocytic necrotizing lymphadenitis 6

Key Clinical Pitfalls to Avoid

Diagnostic Confusion

• Do not diagnose CAEBV in the presence of established lymphoproliferative disorders—use the specific disease name instead 1
• EBV-related hemophagocytic lymphohistiocytosis generally occurs during primary infection, not as initial CAEBV presentation 1

Prognostic Indicators in CAEBV

• Late onset of disease correlates with poorer outcomes 1
• Thrombocytopenia indicates worse prognosis 1
• EBV infection of T cells (rather than B cells) predicts poorer outcomes 1

Population-Specific Considerations

• Immunocompromised patients are at higher risk for severe manifestations and lymphoproliferative complications 1, 2
• Reactivation affects more diverse organ systems compared to primary infection 2