A 40 year old farmer with a history of recurrent attacks of porphyria complains of itching when exposes to the sun and maculopapular rash on sun exposed areas, his symptoms are exaggerated in the summer. The diagnosis is –
**Core Concept**
Porphyria is a group of disorders caused by defects in the production of heme, a vital molecule in the body. These defects lead to the accumulation of porphyrins, which can cause neurological and cutaneous symptoms. In this case, the patient's symptoms are related to the cutaneous manifestations of porphyria, which are exacerbated by sunlight.
**Why the Correct Answer is Right**
The patient's symptoms of itching and maculopapular rash on sun-exposed areas are characteristic of cutaneous porphyria, specifically porphyria cutanea tarda (PCT). PCT is caused by a deficiency in the enzyme uroporphyrinogen decarboxylase (UROD), which is responsible for the conversion of uroporphyrinogen to coproporphyrinogen. This deficiency leads to the accumulation of uroporphyrin, a porphyrin that is highly photosensitive, causing skin symptoms when exposed to sunlight.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the patient's symptoms, as it is not related to porphyria or sunlight exposure.
**Option B:** While porphyria can cause neurological symptoms, the patient's symptoms are primarily cutaneous and related to sunlight exposure, making this option incorrect.
**Option C:** This option is incorrect because it does not specifically relate to the patient's symptoms of itching and maculopapular rash on sun-exposed areas.
**Clinical Pearl / High-Yield Fact**
Porphyria cutanea tarda is often associated with liver disease, iron overload, and genetic mutations. It's essential to consider these factors when evaluating patients with cutaneous porphyria.
**Correct Answer: B. Acute Intermittent Porphyria**