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For further information, see CMDT Part 34-02: Human Herpesviruses
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Essentials of Diagnosis
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Malaise, fever, and (exudative) sore throat
Palatal petechiae, lymphadenopathy, splenomegaly, and, occasionally, a maculopapular rash
Positive heterophile agglutination test or mononucleosis spot test (Monospot)
Atypical large lymphocytes on peripheral blood smear; lymphocytosis
Complications: hepatitis, myocarditis, neuropathy, encephalitis, airway obstruction from adenitis, hemolytic anemia, thrombocytopenia
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General Considerations
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Epstein-Barr virus (EBV) is ubiquitous; infects > 95% of the adult population worldwide and persists for the person's lifetime
Infectious mononucleosis is a common manifestation of EBV infection and may occur at any age
EBV is largely transmitted by saliva but can also be recovered from genital secretions
Saliva may remain infectious during convalescence, for 6 months or longer after symptom onset
The incubation period lasts several weeks (30–50 days)
In the United States, the incidence of EBV infection is declining, although prevalence remains high for those aged 12–19 years
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Fever, sore throat, fatigue, malaise, anorexia, and myalgia typically occur in the early phase of the illness
Physical findings include
Petechiae on soft palate
Exudative pharyngitis, uvular edema, tonsillitis, or gingivitis
Lymphadenopathy (discrete, nonsuppurative, slightly painful, especially along the posterior cervical chain)
Transient bilateral upper lid edema (Hoagland sign); conjunctival hemorrhage
Splenomegaly (in up to 50% of patients, sometimes massive)
Other manifestations
Hepatitis
Interstitial pneumonitis (sometimes with pleural involvement)
Cholestasis
Gastritis
Kidney disease (most often, interstitial nephritis)
Epiglottitis
Nervous system involvement (in 1–5%)
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Differential Diagnosis
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Cytomegalovirus infection
Toxoplasmosis
Acute HIV infection
Secondary syphilis
Human herpes virus 6 (HHV-6) infection
Rubella
Drug hypersensitivity reactions
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Initial granulocytopenia followed within 1 week by lymphocytic leukocytosis with > 10% atypical lymphocytes
Hemolytic anemia (with antibodies) and thrombocytopenia occur occasionally
Serologic evidence of infection
Heterophile sheep cell agglutination (HA) antibody tests or the correlated Monospot test
Usually becomes positive within 4 weeks after onset of illness
Specific but often insensitive in early illness; may be absent in 20% of adults
Immunoglobulins
Immunoglobulin M (IgM) antibody to EB virus capsid antigen (VCA) rises and falls during acute illness
Immunoglobulin G (IgG) antibody to VCA rises and persists for life
IgG antibodies to EBV nuclear antigen (EBNA) appear after 4 weeks of onset and persist
Polymerase chain reaction (PCR) for EBV DNA is useful in the evaluation of malignancies associated with EBV
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No specific antiviral therapy is needed in more than 95% of patients with acute EBV-associated infectious mononucleosis
Non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen and warm saline gargles or throat irrigations three or four times daily can manage symptoms
If a throat culture also grows β-hemolytic streptococci, a 10-day course of penicillin or ...