USMLE Step 2 CK High-Yield Practice Test 2026 - Free Step 2 CK Practice Questions and Study Guide

The symptoms described—peeling skin and a swollen belly in a child—point towards a condition that is often associated with malnutrition, which can indeed be linked to protein deficiency. Protein deficiency can lead to a condition known as kwashiorkor, characterized by abdominal swelling due to edema, as well as changes in the skin, including peeling and dermatitis.

In this context, while vitamin deficiencies can lead to various skin and systemic manifestations, the combination of swollen belly and peeling skin is more classic for protein energy malnutrition. For instance, vitamin A deficiency can lead to keratomalacia and vision problems; vitamin D deficiency can cause rickets affecting bone health; and vitamin C deficiency results in scurvy, which involves bleeding gums and bruising rather than the symptoms mentioned.

Thus, the combination of these symptoms aligns closely with a diagnosis of protein deficiency, making it the most fitting choice.