What are the symptoms and treatment of infectious mononucleosis (mono)?

Symptoms and Treatment of Infectious Mononucleosis (Mono)

Infectious mononucleosis is characterized by a classic triad of fever, tonsillar pharyngitis, and lymphadenopathy, with treatment primarily consisting of supportive care including adequate rest, hydration, and avoidance of contact sports for at least 8 weeks or while splenomegaly is present. 1, 2

Clinical Manifestations

Common Symptoms

• Classic Triad:
  • Fever
  • Tonsillar pharyngitis (sore throat)
  • Lymphadenopathy (particularly posterior cervical or auricular) 2, 3
• Other Frequent Symptoms:
  • Fatigue (may be profound and last up to three months)
  • Headache
  • Nausea, vomiting, and abdominal pain
  • Periorbital/palpebral edema (occurs in approximately one-third of patients) 2
  • Splenomegaly (occurs in approximately 50% of cases)
  • Hepatomegaly (occurs in approximately 10% of cases) 2

Laboratory Findings

• Leukocytosis with lymphocytosis (lymphocytes ≥50% of white blood cell count)
• Atypical lymphocytes (>10% of total lymphocyte count) 2, 3
• Elevated liver enzymes may be present 1

Less Common Manifestations

• Maculopapular rash (occurs in 10-45% of cases), particularly if treated with ampicillin or amoxicillin 2
• Palatal petechiae 3

Diagnosis

Laboratory Testing

• Heterophile antibody test (Monospot): Most widely used initial test, but may be negative early in the course of infection 2, 3
• EBV-specific antibody testing: Most appropriate initial laboratory test for patients with suspected mono 1
  • VCA IgM (+), VCA IgG (+), EBNA IgG (-): Acute primary infection (within 6 weeks)
  • VCA IgM (-), VCA IgG (+), EBNA IgG (+): Past infection (>6 weeks)
  • VCA IgM (-), VCA IgG (-), EBNA IgG (-): No previous EBV infection 1

Treatment

Supportive Care (Mainstay of Treatment)

• Adequate hydration
• Analgesics and antipyretics for pain and fever
• Rest as needed (guided by patient's energy level, but enforced bed rest is not recommended) 2, 3
• Avoidance of contact sports for at least 8 weeks or while splenomegaly is present to prevent splenic rupture 1, 2

Medications

• Not Routinely Recommended:
  • Corticosteroids (except in cases of airway obstruction due to significant tonsillar hypertrophy or severe hematological complications) 1, 3
  • Acyclovir
  • Antihistamines 3

Complications

Potential Complications

• Splenic rupture: Occurs in 0.1-0.5% of cases, potentially life-threatening 2
• Airway obstruction: Due to significant tonsillar hypertrophy 1
• Peritonsillar abscess: Rare complication that may require surgical intervention 4
• Chronic fatigue syndrome: Infectious mononucleosis is a risk factor 2
• Hematological abnormalities: Including thrombocytopenia 1

Special Considerations

Age-Related Presentation

• Primary EBV infection in children under 10 years is usually asymptomatic or shows nonspecific symptoms 5
• Most symptomatic cases occur in adolescents and young adults aged 15-24 years 2

Transmission and Prevention

• Primarily transmitted through saliva ("kissing disease")
• Virus continues to be shed intermittently in saliva for months after recovery 1
• Prevention measures include:
  • Avoiding sharing utensils, glasses, toothbrushes, or food
  • Avoiding kissing or intimate contact during the acute phase
  • Frequent handwashing 1

Prognosis

• Most patients have an uneventful recovery 2
• Fatigue, myalgias, and increased need for sleep may persist for several months after the acute infection has resolved 3
• Approximately 5-6% of patients may develop symptoms consistent with post-infectious fatigue syndrome 1

When to Refer

• Patients with severe symptoms or complications (respiratory compromise, significant splenomegaly)
• Immunocompromised patients who may have atypical presentations 1
• Patients with prolonged symptoms beyond the expected recovery period