Overview
Definition:
Infectious mononucleosis (IM) is a clinical syndrome typically caused by the Epstein-Barr virus (EBV)
It is characterized by fever, pharyngitis, and lymphadenopathy, with a high likelihood of atypical lymphocytosis in peripheral blood smears
Steroids are generally not indicated for routine management but are reserved for specific, severe complications.
Epidemiology:
EBV is ubiquitous, with most individuals infected by adulthood
Primary infection in childhood is often asymptomatic or mild
IM is most commonly diagnosed in adolescents and young adults, with peak incidence between 15-24 years
Transmission occurs primarily through salivary secretions (kissing disease).
Clinical Significance:
Understanding EBV IM is crucial in pediatrics due to its potential for significant morbidity, including airway compromise and splenic rupture
While most cases are self-limiting, recognizing severe presentations requiring specific interventions like steroids is vital for preventing serious complications and ensuring patient safety, a key focus for DNB and NEET SS preparation.
Clinical Presentation
Symptoms:
Classic triad: Fever
Sore throat (severe, exudative pharyngitis/tonsillitis)
Posterior cervical lymphadenopathy
Malaise and fatigue are prominent and can persist for weeks
Headache and abdominal pain may occur
Symptoms typically develop after an incubation period of 4-6 weeks.
Signs:
Generalized lymphadenopathy (anterior and posterior cervical chains most common)
Pharyngeal erythema and exudates, mimicking streptococcal pharyngitis
Palpable spleen (splenomegaly) in 50-75% of cases
Palpable liver (hepatomegaly) in 10-15% of cases
Maculopapular rash can occur, especially if ampicillin or amoxicillin is administered.
Diagnostic Criteria:
A combination of clinical findings and laboratory confirmation
Clinical features: Fever, pharyngitis, lymphadenopathy
Laboratory findings: Heterophile antibody test (Monospot) positive in 80-90% of older children/adults
EBV-specific serology (IgM and IgG antibodies to EBV viral capsid antigen - VCA) is more sensitive and specific, especially in younger children where heterophile antibodies may be absent
Absolute lymphocytosis with a significant proportion of atypical lymphocytes (>10%) on peripheral blood smear.
Diagnostic Approach
History Taking:
Detailed history of onset and duration of fever, sore throat severity, presence of fatigue, exposure to individuals with similar symptoms, recent antibiotic use (especially penicillins), and any risk factors for immunocompromise
Inquire about abdominal pain, which could suggest splenomegaly or splenic rupture.
Physical Examination:
Comprehensive physical examination focusing on vital signs, oropharyngeal assessment for exudates and edema, thorough lymph node palpation (neck, axilla, groin), abdominal palpation for splenomegaly (measure spleen tip below costal margin) and hepatomegaly, and assessment for any rash.
Investigations:
Complete blood count (CBC) with differential: Leukocytosis with a relative lymphocytosis and >10% atypical lymphocytes is characteristic
Heterophile antibody test (Monospot): Rapid screening test, less sensitive in young children
EBV-specific serology: VCA-IgM (acute infection), VCA-IgG (past or current infection), EBNA-IgG (past infection, develops later)
Liver function tests (LFTs): Mild elevations in transaminases are common and usually transient
Imaging: Ultrasound of the abdomen can confirm splenomegaly and rule out other causes of abdominal pain, but is not routine for diagnosis.
Differential Diagnosis:
Streptococcal pharyngitis (Strep throat), Cytomegalovirus (CMV) infection, Adenovirus infection, Primary HIV infection, Diphtheria, Acute lymphoblastic leukemia (ALL) presenting with pharyngitis and lymphadenopathy, Viral hepatitis.
Management
Initial Management:
Supportive care is the mainstay for uncomplicated EBV IM
Rest, hydration, and analgesics (acetaminophen or ibuprofen) for fever and sore throat are recommended
Avoid contact sports and strenuous activity for at least 4 weeks due to the risk of splenic rupture if splenomegaly is present
Advise patients to avoid sharing personal items like cups and utensils.
Medical Management:
Corticosteroids (e.g., prednisone) are GENERALLY NOT RECOMMENDED for routine management of EBV infectious mononucleosis
Their use is controversial due to potential risks of prolonged shedding of EBV and concerns about secondary bacterial infections or reactivation of other latent viruses
Steroids are typically reserved for specific indications where severe complications necessitate their use.
Steroid Indications:
Specific indications for corticosteroid therapy in EBV IM are rare and include: 1
Severe airway obstruction due to massive tonsillar or palatine edema threatening ventilation
This is the most well-established indication and requires urgent intervention
2
Severe, persistent thrombocytopenia (platelet count < 20,000-30,000/µL) or autoimmune hemolytic anemia, although these are less common complications
3
Neurological complications such as encephalitis or meningoencephalitis, where they may be considered as part of a broader management strategy.
Supportive Care:
Pain management with antipyretics and analgesics
Ensuring adequate fluid intake to prevent dehydration, especially with severe pharyngitis
Monitoring for signs of airway compromise
Education on activity restrictions to prevent splenic injury
Close follow-up for any worsening symptoms or development of complications.
Complications
Early Complications:
Airway obstruction due to severe tonsillar/palatine edema
Splenic rupture (rare but life-threatening, often associated with trauma or vigorous physical activity)
Hematological complications: Thrombocytopenia, hemolytic anemia, neutropenia
Neurological complications: Guillain-Barré syndrome, encephalitis, meningoencephalitis, Bell's palsy
Hepatitis
Myocarditis (rare).
Late Complications:
Post-viral fatigue syndrome
Reactivation of EBV in immunocompromised individuals
Increased risk of certain lymphoid malignancies (e.g., Hodgkin lymphoma, Burkitt lymphoma) in genetically susceptible individuals or in the context of significant immunosuppression, though primary IM itself does not directly cause these in otherwise healthy individuals.
Prevention Strategies:
Strict adherence to activity restrictions (avoiding contact sports for at least 4 weeks if splenomegaly is present) is crucial to prevent splenic rupture
Prompt recognition and management of airway compromise
Careful consideration of antibiotic use, as rash can occur with penicillins
Avoiding unnecessary immunosuppression.
Prognosis
Factors Affecting Prognosis:
Most children and adolescents recover fully from EBV IM within 2-4 weeks, although fatigue can persist for several months
Factors influencing prognosis include the severity of initial symptoms, presence of complications, and the patient's underlying immune status
Severe airway compromise or splenic rupture carries a poorer prognosis if not managed promptly.
Outcomes:
For the vast majority of pediatric patients, the outcome is excellent with complete recovery
Recurrence of EBV IM is rare
Long-term sequelae are uncommon in immunocompetent individuals.
Follow Up:
Follow-up is primarily focused on monitoring symptom resolution, particularly fatigue and lymphadenopathy
Patients should be advised to return if they develop severe abdominal pain, shortness of breath, or signs of dehydration
For cases requiring steroid intervention, close monitoring for side effects and resolution of the indication is essential.
Key Points
Exam Focus:
Steroids are reserved for specific, severe indications in EBV IM, NOT routine management
Key indications are airway compromise, severe thrombocytopenia/hemolytic anemia, and rare neurological issues
The risk of splenic rupture necessitates activity restrictions.
Clinical Pearls:
Suspect EBV IM in adolescents with fever, severe pharyngitis, and posterior cervical lymphadenopathy
Differentiate from strep pharyngitis
Remember that the Monospot test can be negative in young children
EBV-specific serology is more reliable
ALWAYS ask about abdominal pain in a child with IM
it could be splenomegaly or rupture.
Common Mistakes:
Prescribing antibiotics like amoxicillin/ampicillin without considering the possibility of EBV IM, which can lead to a morbilliform rash
Using steroids empirically for pharyngitis without clear evidence of severe airway compromise
Underestimating the duration of fatigue
Failing to advise on activity restrictions for patients with splenomegaly.