Management of a 12-Year-Old Boy with Positive Heterophile Antibodies and Negative EBV Antibodies
Supportive care is the recommended treatment for this patient with a diagnosis of infectious mononucleosis, likely due to acute cytomegalovirus infection rather than Epstein-Barr virus.
Diagnostic Interpretation
This patient presents with an unusual serologic pattern:
- Positive heterophile antibodies
- Negative EBV antibodies
This pattern suggests:
- Infectious mononucleosis syndrome not caused by EBV
- Most likely diagnosis is cytomegalovirus (CMV) infection, which can cause heterophile-positive mononucleosis-like illness 1
- This is an atypical but documented presentation in pre-teens
Treatment Recommendations
First-line Management
- Supportive care only 2
- Adequate rest
- Hydration
- Antipyretics for fever
- Analgesics for sore throat and discomfort
Important Restrictions
- Avoid contact sports for at least 3 weeks from symptom onset 3, 2
- No participation until spleen is no longer palpable
- May take 3-6 months for complete return to pre-illness athletic performance 4
What NOT to Do
Monitoring and Follow-up
Physical Examination Focus
- Monitor for:
- Hepatosplenomegaly
- Posterior cervical lymphadenopathy
- Signs of rare complications
Laboratory Monitoring
- Complete blood count with differential
- Look for >40% lymphocytes and >10% atypical lymphocytes 2
- Liver function tests
- Elevated liver enzymes are common and support diagnosis 2
Return to Activities
- Assess spleen size at follow-up visits
- Return to contact sports only when spleen is normal size 4
- Gradual return to full activity
Special Considerations
Differential Diagnosis
- CMV mononucleosis (most likely)
- False-negative EBV antibody test (early in disease course)
- Other viral infections causing mononucleosis-like illness
When to Consider Additional Testing
- If symptoms persist beyond expected timeframe
- If atypical features develop
- Consider CMV-specific antibody testing to confirm diagnosis 1
Potential Complications
Rare but Serious
- Splenic rupture (very rare but serious)
- Significant hepatitis
- Airway obstruction from severe tonsillar hypertrophy
- Neurological complications
Long-term Considerations
- Most patients recover completely within 2-4 weeks
- Fatigue may persist for several months in some cases
Key Points for Parents
- This is a self-limited viral illness
- Rest is essential for recovery
- Strict avoidance of contact sports until medically cleared
- No specific antiviral treatment is beneficial
- Regular follow-up to monitor recovery and spleen size
This approach focuses on supportive care while monitoring for potential complications, with particular attention to avoiding activities that could risk splenic injury during the recovery period.