What condition results from a deficiency in uroporphyrinogen decarboxylase?

A deficiency in uroporphyrinogen decarboxylase leads to porphyria cutanea tarda, which is characterized by the accumulation of porphyrins, specifically uroporphyrin. This condition primarily affects the skin, leading to photosensitivity and the formation of blisters or erosions upon sun exposure due to the skin's inability to adequately manage the porphyrin build-up.

Porphyria cutanea tarda is considered the most common type of porphyria and often has an acquired component, with risk factors including liver disease, alcohol consumption, and estrogen use. The underlying enzymatic deficiency disrupts porphyrin metabolism, leading to symptoms that are particularly prominent in sun-exposed areas of the skin.

In contrast, the other conditions listed do not involve uroporphyrinogen decarboxylase deficiency and present with different clinical features and pathophysiological mechanisms. For example, acute intermittent porphyria results from a deficiency in porphobilinogen deaminase, while hereditary spherocytosis relates to abnormalities in red blood cell membrane proteins. Lead poisoning, on the other hand, is associated with inhibition of heme synthesis, particularly affecting the enzymes involved in earlier steps and causing a different set