What is the management approach for a 15-25 year old patient with infectious mononucleosis caused by the Epstein-Barr virus, presenting with fever, sore throat, fatigue, and lymphadenopathy?

Management of Infectious Mononucleosis in Adolescents and Young Adults

Treatment of infectious mononucleosis is primarily supportive, focusing on symptom management with activity restriction and avoidance of contact sports or strenuous exercise for 8 weeks to prevent splenic rupture, which is the most feared complication. 1, 2

Diagnosis Confirmation

• Clinical presentation typically includes the classic triad of fever, tonsillar pharyngitis, and cervical lymphadenopathy, with fatigue being profound but usually resolving within three months 1
• Laboratory findings show peripheral blood leukocytosis with lymphocytes comprising at least 50% of the white blood cell differential count, and atypical lymphocytes constituting more than 10% of total lymphocytes 1
• Heterophile antibody testing (Monospot test) is the most widely used diagnostic method for infectious mononucleosis 1, 3
• EBV-specific antibody testing should be performed when confirmation is required in patients with mononucleosis-like illness and a negative Monospot test, specifically looking for IgM antibody to EBV viral capsid antigen (VCA), which indicates acute primary infection 1, 3

Supportive Management

• Activity modification with reduction of activity and bed rest as tolerated is recommended 1
• Sports restriction requires patients to avoid contact sports or strenuous exercise for 8 weeks or while splenomegaly is still present 1, 2
• Symptom management focuses on controlling fever, sore throat, and fatigue through supportive measures 1
• No role for antivirals or corticosteroids in routine management of uncomplicated infectious mononucleosis 2

Physical Examination Findings to Monitor

• Splenomegaly occurs in approximately 50% of cases and requires careful monitoring 1
• Hepatomegaly is present in approximately 10% of cases 1
• Periorbital and/or palpebral edema, typically bilateral, occurs in one-third of patients 1
• Skin rash (erythematous, maculopapular, widely scattered) occurs in 10-45% of cases 1

Critical Complications Requiring Immediate Evaluation

Splenic Rupture

• Spontaneous splenic rupture occurs in 0.1-0.5% of patients and is potentially life-threatening 1, 3
• Timing typically occurs within the first month of symptom onset 2
• This complication is the primary reason for strict activity restriction 2

Persistent Fever Beyond 10 Days

• Chronic Active EBV Infection (CAEBV) should be suspected with persistent or recurrent infectious mononucleosis-like symptoms, requiring quantitative EBV PCR showing viral loads >10^2.5 copies/μg DNA in peripheral blood mononuclear cells 4
• Hemophagocytic Lymphohistiocytosis (HLH) presents with persistent fever, cytopenias, and extremely elevated ferritin levels (>1000 ng/mL), requiring bone marrow examination if suspected 4
• Secondary bacterial infection can occur during recovery from primary EBV infection 4

Common Pitfalls to Avoid

• Assuming all EBV infections are self-limiting can lead to delayed diagnosis of CAEBV or HLH, both requiring aggressive management with poor prognosis if untreated 4
• Overlooking HLH can be life-threatening and requires prompt recognition and immunosuppressive therapy 4
• Premature return to sports before 8 weeks or resolution of splenomegaly increases risk of splenic rupture 1, 2
• Prescribing ampicillin or amoxicillin should be avoided as these antibiotics commonly cause a maculopapular rash in patients with infectious mononucleosis 1

Prognosis

• Most patients have an uneventful recovery with infectious mononucleosis being generally benign and self-limited 1
• Fatigue typically resolves within three months though it may be profound initially 1
• Long-term sequelae include infectious mononucleosis being a risk factor for chronic fatigue syndrome 1
• Rare progression to T-cell or NK-cell malignant lymphomas can occur in patients with CAEBV 4