A 5-year-old boy presents with recurrent painful swelling of hands and feet (dactylitis), severe anemia (Hb 6 g/dL), and jaundice. Peripheral smear shows sickle-shaped red cells and target cells. Hemoglobin electrophoresis confirms Hb SS disease. Which of the following organisms most commonly causes life-threatening sepsis in this child due to functional asplenia?

• A Staphylococcus aureus
• B Escherichia coli
• C Haemophilus influenzae type b
• D Streptococcus pneumoniae ✓

Explanation

Children with sickle cell disease (HbSS) develop functional asplenia due to repeated splenic infarctions from sickling, typically by age 5 years. The spleen is critical for opsonization and clearance of encapsulated organisms. Therefore, these children are at dramatically increased risk of overwhelming sepsis from encapsulated bacteria, most notably Streptococcus pneumoniae, followed by H. influenzae type b. Prophylactic penicillin from infancy and pneumococcal vaccination are essential preventive measures.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.