An infant with concurrent serotype 6C invasive pneumococcal disease and infectious mononucleosis

Area of Science:

• Pediatrics
• Infectious Diseases
• Microbiology

Background:

• Streptococcus pneumoniae is a primary cause of invasive bacterial infections.
• Invasive pneumococcal disease (IPD) and viral infectious mononucleosis (IM) are typically considered separate conditions.

Observation:

• An 11-month-old infant presented with symptoms of sepsis, including fever, leukopenia, tachycardia, tachypnea, and agranulocytosis.
• Clinical signs included tonsillitis, cervical adenopathy, and hepatosplenomegaly.
• The infant was diagnosed with sepsis and received broad-spectrum antibiotics, antiviral therapy, and granulocyte transfusions.

Findings:

• Invasive pneumococcal disease (IPD) was confirmed by isolation of Streptococcus pneumoniae serotype 6C from blood cultures.
• Infectious mononucleosis (IM) was diagnosed concurrently through Epstein-Barr viral DNA quantitation and fluctuating antibody titers.
• The infant's condition improved following treatment, with gradual fever reduction and general improvement.

Implications:

• This case underscores the rare but critical possibility of simultaneous IPD and IM.
• Clinicians should consider concurrent infections in infants presenting with severe symptoms.
• Early diagnosis and comprehensive treatment are vital for managing such complex pediatric infections.