A 48-year-old man comes to the physician for a follow-up appointment. He has a 2-week history of blisters on his forearms that occurred after he took a long bike ride in a park. He has a long history of alcohol consumption and IV drug use. Decreased activity of which of following is the most likely explanation for this patient’s presentation?
A) Delta-aminolevulinic acid dehydratase
B) Delta-aminolevulinic acid synthase
C) Ferrochelatase
D) Porphobilinogen deaminase
E) Uroporphyrinogen decarboxylase
