Which finding is seen on a peripheral smear in lead poisoning?

Which finding is seen on a peripheral smear in lead poisoning?

• A. Basophilic stippling
• B. Eosinophilia
• C. Macrocytosis without basophilic stippling
• D. Sideroblastic features

Answer: (A)

Basophilic stippling on a peripheral smear reflects disrupted red cell RNA processing from lead exposure. Lead inhibits enzymes in heme synthesis, specifically δ-aminolevulinic acid dehydratase and ferrochelatase. When these enzymes are blocked, ribosomal RNA accumulates and remains as small, bluish granules inside red blood cells. That granular basophilic appearance is the classic smear finding in lead poisoning. This condition often presents with microcytic, hypochromic anemia, aligning with impaired heme production. Other options aren’t typical for the smear: eosinophilia isn’t a feature of lead poisoning, macrocytosis without stippling points away from this scenario, and sideroblastic features are primarily a marrow finding (ring sideroblasts) rather than a characteristic peripheral smear finding.

Basophilic stippling on a peripheral smear reflects disrupted red cell RNA processing from lead exposure. Lead inhibits enzymes in heme synthesis, specifically δ-aminolevulinic acid dehydratase and ferrochelatase. When these enzymes are blocked, ribosomal RNA accumulates and remains as small, bluish granules inside red blood cells. That granular basophilic appearance is the classic smear finding in lead poisoning.

This condition often presents with microcytic, hypochromic anemia, aligning with impaired heme production. Other options aren’t typical for the smear: eosinophilia isn’t a feature of lead poisoning, macrocytosis without stippling points away from this scenario, and sideroblastic features are primarily a marrow finding (ring sideroblasts) rather than a characteristic peripheral smear finding.