Which of the following is not true about Porphyria cutanea tarda (PCT)
**Core Concept**
Porphyria cutanea tarda (PCT) is a type of porphyria characterized by a deficiency of the enzyme uroporphyrinogen decarboxylase (UROD), leading to an accumulation of porphyrins in the skin. This results in photosensitivity and blistering skin lesions.
**Why the Correct Answer is Right**
PCT is typically associated with liver disease, particularly hepatitis C, and is often seen in individuals with hemochromatosis. The accumulation of porphyrins in the skin is due to the impaired activity of UROD, which is necessary for the conversion of uroporphyrinogen to coproporphyrinogen. This deficiency leads to the accumulation of uroporphyrin and other porphyrins, which are then excreted in the urine and deposited in the skin, causing photosensitivity and blistering.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because PCT is indeed characterized by a deficiency of the enzyme uroporphyrinogen decarboxylase (UROD).
**Option B:** This option is incorrect because PCT is often associated with liver disease, particularly hepatitis C, and is not typically a benign condition.
**Option C:** This option is incorrect because PCT is a type of porphyria that is indeed characterized by an accumulation of porphyrins in the skin.
**Clinical Pearl / High-Yield Fact**
A key clinical feature of PCT is the presence of blistering skin lesions on sun-exposed areas, particularly the hands and face. Patients with PCT may also experience scarring, hyperpigmentation, and fragility of the skin.
**Correct Answer: D.**