Acrodermatitis enteropathica is due to deficiency of
**Core Concept**
Acrodermatitis enteropathica is a rare, inherited disorder characterized by impaired zinc absorption, leading to zinc deficiency. This condition is caused by mutations in the SLC39A4 gene, which encodes a zinc transporter responsible for zinc uptake in the intestine.
**Why the Correct Answer is Right**
The correct answer is zinc because it is essential for various cellular processes, including protein synthesis, DNA replication, and immune function. Zinc deficiency impairs the integrity of the skin and mucous membranes, leading to skin lesions, hair loss, and gastrointestinal symptoms. The SLC39A4 gene plays a crucial role in regulating zinc homeostasis, and mutations in this gene disrupt zinc absorption, resulting in the development of acrodermatitis enteropathica.
**Why Each Wrong Option is Incorrect**
**Option A:** Iron deficiency is not directly related to acrodermatitis enteropathica, although both can cause anemia. However, iron and zinc deficiencies have distinct clinical presentations and underlying pathophysiology.
**Option B:** Vitamin D deficiency can cause skin lesions and osteomalacia, but it is not the primary cause of acrodermatitis enteropathica.
**Option C:** Folate deficiency can lead to megaloblastic anemia, but it is not associated with the skin and mucous membrane lesions characteristic of acrodermatitis enteropathica.
**Clinical Pearl / High-Yield Fact**
Acrodermatitis enteropathica is a rare but important condition to recognize, as it can be treated with zinc supplementation, which often leads to rapid improvements in symptoms.
**Correct Answer:** A. Zinc