Morning Quiz ☕️ 

A 5-year-old boy of African descent presents to the Emergency Department (ED) with:

• Severe abdominal pain (clutching abdomen and crying).

• History of intermittent episodes since 5 months of age, including:

  • Jaundice

  • Joint and bone pain

Examination Findings

• Vital signs: Within normal limits.

• Physical exam:

  • Slight jaundice

  • Pale conjunctiva (suggestive of anemia)

  • Tender, easily palpable spleen

Diagnostic Workup

• CBC with peripheral blood smear: Crescent-shaped RBCs 

• Abdominal ultrasonography: Splenic infarct.

Management

• Partial splenectomy performed.

• Postoperative vaccinations administered against:

  • Neisseria meningitidis

  • Haemophilus influenzae

  • Streptococcus pneumoniae

Question

An image depicts a slide from the resected spleen.

Which functional zone(s) of the spleen protects against these encapsulated bacteria?

Options:

A. 2 only

B. 1 only

C. 3 only

D. 1 and 2

E. 1,2 and 3

Correct Answer 🎯:1 and 2

⚙️

Underlying Genetic Defect (HbS Mutation)

⬇

Abnormal Hemoglobin (HbS) Polymerization under low O₂ tension

⬇

Sickling of RBCs → ↑ Rigidity & Fragility

⬇

Chronic Hemolysis → Jaundice (↑ Unconjugated Bilirubin) + Anemia (Pale

Conjunctiva)

⬇

Vaso-occlusion in Microvasculature (Due to sickled RBCs adhering to

endothelium)

⬇

Ischemia in Spleen (High sinusoidal pressure traps sickled RBCs)⬇

Splenic Infarcts (Acute: Abdominal Pain; Chronic: Autosplenectomy)

⬇

Loss of Splenic Function (Functional Asplenia)

⬇

Inability to Clear Encapsulated Bacteria (Marginal Zone & White Pulp destroyed)

⬇

↑ Risk of Infection (S. pneumoniae, H. influenzae, N. meningitidis)

Differential Table ⚖️

Practice Questions ⏳️ 

Stay Hungry, Stay Curious!

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Dr. Shoaib Ahmad

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