Which of the following features is associated with Pyloric Stenosis?

Visible gastric peristalsis is a distinctive feature associated with pyloric stenosis, a condition where the pylorus, the opening from the stomach to the small intestine, becomes narrowed. This narrowing leads to delayed gastric emptying, causing the stomach to contract more forcefully in an effort to push contents through the pylorus. As a result, these vigorous contractions can be visually observed as peristaltic waves, especially in the upper abdomen. This observable activity is particularly noticeable when the infant is lying on their back, contributing to the characteristic appearance of severe projectile vomiting that often accompanies this condition.

In contrast, while abdominal bloating and dramatic weight loss can occur in various gastrointestinal conditions, they are not specific indicators of pyloric stenosis. Severe constipation may occur but is not a primary symptom of this condition; instead, the vomiting and dehydration resulting from the inability to pass food through the narrowed pylorus are more characteristic findings.