Sleep Features of Infectious Mononucleosis
Infectious mononucleosis is characterized by profound and prolonged fatigue that significantly disrupts sleep patterns, with patients experiencing excessive need for sleep and daytime somnolence that can persist for weeks to months after acute infection resolves. 1
Primary Sleep-Related Manifestations
Fatigue and Hypersomnia
- Fatigue is one of the cardinal symptoms of infectious mononucleosis, presenting alongside fever, pharyngitis, and lymphadenopathy 2, 3
- The fatigue is typically severe and debilitating, lasting several weeks during acute illness 4, 5
- Patients experience a markedly increased need for sleep during the acute phase, with activity levels severely limited by exhaustion 1
- Fatigue, myalgias, and excessive need for sleep may persist for several months after the acute infection has resolved, representing one of the most troublesome long-term sequelae 1
Sleep Pattern Disruption
- The profound fatigue leads to altered sleep-wake cycles, with patients requiring extended periods of rest 1
- Bed rest should not be enforced; rather, the patient's energy level should guide activity, acknowledging that sleep needs are significantly elevated 1
- The excessive daytime somnolence and prolonged nighttime sleep represent the body's response to the viral infection and immune activation 6
Clinical Context and Duration
Acute Phase (First 2-3 Weeks)
- Sleep disturbance coincides with peak symptoms including high fever (up to 40°C), severe sore throat, and hepatosplenomegaly 2, 4
- The combination of systemic symptoms and profound fatigue creates maximal sleep disruption during this period 5, 6
Recovery Phase (Weeks to Months)
- While most acute symptoms resolve within 2-3 weeks, fatigue and increased sleep requirements commonly persist for several months 4, 1
- This protracted fatigue phase is a distinguishing feature of infectious mononucleosis compared to other viral pharyngitides 5
Clinical Implications
Activity Recommendations
- Patients should be withdrawn from contact or collision sports for at least four weeks after symptom onset 1
- Activity restrictions should account for ongoing fatigue and sleep disturbance beyond the acute illness phase 1
- The patient's subjective energy level and sleep requirements should guide return to normal activities 1
Differential Considerations
- When evaluating patients with pharyngitis and fatigue, the presence of significant fatigue with increased sleep needs in patients 10-30 years of age strongly suggests infectious mononucleosis rather than simple viral pharyngitis 1, 3
- The severity and duration of fatigue/sleep disturbance helps distinguish EBV infectious mononucleosis from other causes like cytomegalovirus or toxoplasmosis 1