What is the recommended management for infectious mononucleosis in an adolescent, including supportive care, activity restrictions, medication use, and indications for corticosteroids?

Management of Infectious Mononucleosis in Adolescents

Infectious mononucleosis should be managed primarily with supportive care alone, as antiviral therapy provides no clinical benefit and corticosteroids are reserved only for life-threatening complications such as airway obstruction or increased intracranial pressure. 1, 2

Supportive Care (Primary Treatment)

• Provide symptomatic relief with antipyretics for fever and adequate hydration 2
• Recommend rest as tolerated, but strict bed rest is not necessary 3
• Most patients experience spontaneous resolution within 2-3 weeks, though fatigue may persist for up to 3 months 3

Activity Restrictions

Patients must avoid contact sports and strenuous exercise for 8 weeks from symptom onset or until splenomegaly resolves, whichever is longer. 3 This restriction is critical because:

• Splenic rupture occurs in 0.1-0.5% of cases and is potentially life-threatening 3
• Splenomegaly is present in approximately 50% of patients 3
• The risk of rupture persists even after clinical symptoms improve

Medication Use

Antivirals: NOT Recommended

• Acyclovir is not recommended for routine treatment of infectious mononucleosis 1, 4
• While acyclovir inhibits EBV replication in vitro, meta-analysis of 5 clinical trials demonstrated no clinical benefit 1
• Antivirals may suppress viral shedding during treatment, but this effect is not sustained after discontinuation and does not improve clinical outcomes 4

Corticosteroids: Limited Indications Only

Corticosteroids are NOT recommended for routine symptom control but may be indicated only in the following life-threatening situations: 1, 2, 5

• Airway obstruction or impending airway compromise 1
• Increased intracranial pressure in patients with neurologic complications 1

The evidence for corticosteroids is weak:

• A Cochrane review found no sustained benefit for symptom control, with only transient improvement in sore throat at 12 hours that was not maintained 5
• Across 8 of 10 assessments, no health improvement was found with steroid therapy 5
• Adverse events including respiratory distress and acute onset of diabetes have been reported, though causality is uncertain 5

Avoid Ampicillin/Amoxicillin

• Do not prescribe ampicillin or amoxicillin, as these cause a maculopapular rash in 10-45% of patients with infectious mononucleosis 3

Common Pitfalls to Avoid

• False-negative heterophile antibody (Monospot) tests are common early in infection (before day 6-10) and in children under 10 years 2
• If clinical suspicion is high with negative Monospot, obtain EBV-specific serology: VCA IgM with or without VCA IgG in the absence of EBNA antibodies indicates recent primary infection 2
• Pharyngitis is not always present—the classic triad of fever, pharyngitis, and lymphadenopathy may be incomplete 6
• Periorbital/palpebral edema occurs in one-third of patients and is a helpful diagnostic clue 3

Special Considerations for Immunocompromised Patients

If the patient is immunocompromised, a different approach is warranted:

• Obtain full blood count, blood film, liver function tests, and EBV serology 1
• Consider reducing or discontinuing immunomodulator therapy if possible 1, 2
• In severe primary EBV infection in immunocompromised patients, antiviral therapy with ganciclovir or foscarnet may be considered despite lack of supporting evidence 1, 2
• Seek specialist consultation for suspected lymphoproliferative disease or lymphoma 1
• Symptoms may be minimal in patients receiving corticosteroids, making diagnosis more challenging 2

Expected Clinical Course

• Most patients have an uneventful recovery with complete resolution 3
• Fatigue may persist for up to 3 months but typically resolves 3
• Infectious mononucleosis is a risk factor for chronic fatigue syndrome in approximately 10% of patients at 6-month follow-up 3
• Patients should be counseled about the benign, self-limited nature of the disease to avoid unnecessary investigations and treatments 3