Epstein‑Barr Virus (EBV) Clinical Manifestations and Complications – Evidence‑Based Summary

Primary EBV Infection (Infectious Mononucleosis)

• EBV infection most commonly presents as infectious mononucleosis, characterized by fever, cervical lymphadenopathy, pharyngotonsillitis, and hepatosplenomegaly in the majority of patients. 1
• Persistent fatigue may last for weeks to months after the acute illness. 1
• Sore throat accompanied by tender cervical lymph nodes is a frequent symptom. 2
• Headache, muscle aches, and joint pains are common constitutional complaints. 2

Acute Multisystem Complications of Primary Infection

• Primary EBV infection can involve multiple organ systems, leading to a range of acute complications. 2

Chronic Active EBV Infection (CAEBV)

Defining Clinical Features

• Patients experience persistent or intermittent fever lasting several months. [1][3]
• Chronic massive cervical lymphadenopathy is typical and does not resolve spontaneously. 1
• Severe cases may develop interstitial pneumonitis. 1
• Thrombocytopenia occurs frequently and is linked to a poorer prognosis. [1][4]
• Polyclonal hypergammaglobulinemia is commonly observed. 1

Cardiovascular Manifestations

• Coronary artery aneurysms are a notable cardiovascular risk in CAEBV. [2][5]
• Valvular heart disease can arise during chronic infection. [2][5]

Cutaneous and Dermatologic Findings

• Marked hypersensitivity to mosquito bites may indicate an underlying granular lymphocyte proliferative disorder. [2][5]6
• Hydroa vacciniforme‑like skin eruptions are associated with T‑cell or NK‑cell lymphoproliferative disorders. 2

EBV‑Associated Malignancies

• T‑cell or NK‑cell lymphoproliferative disorders and lymphomas can develop during the course of CAEBV. [1][4]
• Endemic Burkitt lymphoma is etiologically linked to EBV infection. [7][4]
• Undifferentiated nasopharyngeal carcinoma is strongly associated with EBV. [7][4]

Diagnostic and Clinical Pitfalls

• CAEBV should not be diagnosed when an established lymphoproliferative disorder is present; the specific disease entity must be used instead. [1][4]
• EBV‑related hemophagocytic lymphohistiocytosis typically occurs during primary infection rather than as an initial presentation of CAEBV. [2][5]

Prognostic Indicators in CAEBV

• Late onset of disease correlates with inferior outcomes. 1
• Presence of thrombocytopenia predicts a worse prognosis. 1
• Infection of T‑cells (instead of B‑cells) by EBV is associated with poorer survival. 1

Risk in Immunocompromised Populations

• Immunocompromised individuals have a higher risk for severe EBV manifestations and lymphoproliferative complications. 7

Chronic Active Epstein‑Barr Virus Infection (CAEBV): Diagnostic Framework

Overview

• Chronic active Epstein‑Barr virus infection presents with urticaria and painful cervical lymphadenopathy and is a rare, potentially life‑threatening disorder marked by persistent viral replication, systemic inflammation, and clonal proliferation of EBV‑infected lymphocytes. 8

Diagnostic Criteria

• The diagnosis requires fulfillment of three categories: (1) persistent or recurrent infectious‑mononucleosis‑like symptoms such as fever, chronic massive cervical lymphadenopathy, and hepatosplenomegaly; (2) abnormal EBV serology—anti‑VCA IgG ≥ 1:640 and anti‑EA IgG ≥ 1:160—and/or EBV DNA load ≥ 10,000 IU/mL in whole blood; and (3) exclusion of other diseases that could explain the presentation. 8

Essential Diagnostic Workup

• Identification of the EBV‑infected cell lineage (T‑cell, NK‑cell, or B‑cell) is performed by double staining for EBER or EBV DNA together with appropriate cell‑lineage markers. 8

Serological Testing

• Recommended serologic profile includes VCA‑IgG ≥ 1:640, EA‑IgG ≥ 1:160, and frequently positive IgA antibodies to VCA and/or EA. 8

Diagnostic Pitfalls

• CAEBV should not be diagnosed when an established lymphoproliferative disorder (e.g., T‑cell or NK‑cell lymphoma) is already present; instead, the specific lymphoma name is used. CAEBV represents a pre‑malignant state that can evolve into EBV‑associated T‑cell or NK‑cell lymphoproliferative disorders and lymphomas. 8

EBV DNA Quantification and Monitoring Guidelines

Specimen Selection for EBV DNA Testing

• Whole blood, plasma, and serum are all validated specimen types for quantitative EBV DNA PCR, allowing flexibility in sample collection for assessing active viral replication. 9

Interpretation of Serial EBV DNA Measurements

• An upward trend in quantitative EBV DNA levels on serial testing is indicative of active EBV reactivation rather than stable latent infection, supporting the need for clinical reassessment and possible therapeutic intervention. 9

Monitoring Protocols for Immunocompromised Patients

• In high‑risk immunocompromised individuals (e.g., post‑transplant or undergoing intensive chemotherapy), weekly quantitative EBV DNA testing should commence no later than four weeks after the initiating event to enable early detection of viral reactivation. 9
• Monitoring should be continued for a minimum of four months after the high‑risk event, with extension of the surveillance period in patients demonstrating delayed T‑cell immune reconstitution. 9
• Any observed rise in EBV DNA levels during routine surveillance should trigger an increase in sampling frequency to promptly identify and manage potential reactivation. 9