A 5-year-old boy from an older home with peeling paint presents with developmental delay, abdominal pain, and constipation. Vital signs: BP 102/68 mmHg, HR 98/min, RR 20/min, temp 37°C. Blood smear reveals microcytic anemia with basophilic stippling. Laboratory studies show blood lead level 72 mcg/dL (markedly elevated), hemoglobin 9.2 g/dL, and normal reticulocyte count. No fever or recent infections noted. Which mechanism best explains this patient's anemia?
- A)Defective spectrin anchoring to the membrane
- B)Inhibition of ferrochelatase and ALA dehydrataseGABARITO
- C)Oxidation of hemoglobin iron to Fe3+
- D)Autoimmune destruction of red blood cells by IgG
- E)Decreased erythropoietin production by the kidney
Explicação
Lead poisoning inhibits ferrochelatase and ALA dehydratase, impairing heme synthesis and causing microcytic anemia with basophilic stippling. Neurodevelopmental problems and abdominal pain are classic associated findings. Ver explicação completa e trilha adaptativa →