In infants with pyloric stenosis, palpation of an "olive-shaped" mass in the abdomen should be cross-checked with which clinical feature?

1. A

   Projectile bilious vomiting

2. B

   Single visible gastric peristaltic wave

3. C

   Recurrent diarrhea

4. D

   Hematemesis

Appeared in: NORCET 9 Mains - 2025

Explanation

Listen in Hindi

• In hypertrophic pyloric stenosis (HPS), the pyloric sphincter muscle becomes abnormally thickened, creating a gastric outlet obstruction.
• The palpable 'olive-shaped' mass is this hypertrophied muscle.
• To overcome this blockage, the stomach's smooth muscle undergoes very strong, forceful contractions.
• These contractions are often visible through the thin abdominal wall of an infant as peristaltic waves moving from the left upper quadrant to the right, especially after a feed.
• This visible peristalsis is a classic sign that directly corroborates the presence of a gastric outlet obstruction, which is also indicated by the palpable 'olive'.

Why Other Options Were Wrong

• Option A: The vomiting in pyloric stenosis is characteristically non-bilious. The obstruction is proximal to the ampulla of Vater, where bile enters the duodenum, so bile does not mix with gastric contents.
• Option C: Pyloric stenosis causes a gastric outlet obstruction, which prevents food from passing into the intestines. This typically leads to decreased stool output or constipation, not diarrhea.
• Option D: While minor streaks of blood can occur from esophageal irritation (Mallory-Weiss tear) due to forceful vomiting, significant hematemesis is not a typical or primary feature of pyloric stenosis.

Related Visual

Clinical Relevance

• Nursing practice connection: Knowing Clinical signs of hypertrophic pyloric stenosis helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
• A nurse's primary role in assessing an infant with suspected pyloric stenosis includes observing feeding patterns, characterizing vomiting (force, content), and attempting to palpate for the 'olive' mass and observe for peristaltic waves.
• Pre-operative nursing care is critical and focuses on correcting dehydration and electrolyte imbalances (hypochloremic, hypokalemic metabolic alkalosis) with IV fluids, maintaining NPO status, and potentially using an NG tube for gastric decompression.
• Post-operatively, the nurse carefully manages the reintroduction of feeds, starting with small, frequent amounts and monitoring for any persistent vomiting, which could indicate surgical complications.

How to Approach the Question

• First, identify the core condition presented in the question: hypertrophic pyloric stenosis (HPS) in an infant.
• Recall the classic triad of signs for HPS: 1) a palpable 'olive-shaped' mass, 2) projectile, non-bilious vomiting, and 3) visible gastric peristalsis.
• The question asks for a feature to 'cross-check' with the palpable mass. This means you are looking for another one of the classic signs.
• Evaluate each option against the known pathophysiology of HPS.
• Option A mentions 'bilious' vomiting, which is incorrect for HPS because the obstruction is before the entry of bile. Eliminate this option.
• Option B describes the visible peristaltic wave, which is a classic sign caused by the stomach's forceful attempt to push contents past the obstruction. This is a strong candidate.

Concept Tested & Keywords

• Concept Tested: Clinical signs of hypertrophic pyloric stenosis
• Stem keywords: infants, pyloric stenosis, olive-shaped mass
• Lead-in keywords: cross-checked with
• Clinical cues: The presence of an 'olive-shaped' mass is a pathognomonic physical finding for pyloric stenosis.

Question ID

Q7dbaHUMUqfXOKOuOt1hWv

Copy ID

Reference Book

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 58-60

E6 Ghai Essential Pediatrics(pp 26-904 of 913) p. 295-297