A 3 year old boy is brought to the clinic because of abdominal pain, constipation, and decreased energy. His family recently moved into an older home that is undergoing renovation. Examination shows mild developmental delay. Laboratory studies reveal microcytic anemia and basophilic stippling. Lead toxicity most directly inhibits which of the following enzymes?
- A)ALA dehydratase and ferrochelataseGABARITO
- B)Uroporphyrinogen decarboxylase and ferrochelatase
- C)Biliverdin reductase and heme oxygenase
- D)ALA synthase and heme oxygenase
- E)Porphobilinogen deaminase and ALA synthase
Explicação
Lead poisoning inhibits delta aminolevulinate dehydratase and ferrochelatase, impairing heme synthesis and causing microcytic anemia, abdominal pain, and neurocognitive dysfunction. Basophilic stippling and exposure to old paint are classic clues. The block in... Ver explicação completa e trilha adaptativa →