On palpation, an olive-shaped mass in the epigastrium to the right of the midline is indicative of?

Appeared in: MNS 2024

Explanation

The hallmark physical finding for hypertrophic pyloric stenosis is a palpable, firm, mobile, olive-shaped mass located in the epigastrium, just to the right of the umbilicus.
This mass is the thickened pyloric muscle, which causes a gastric outlet obstruction.
This condition typically presents in infants aged 2-8 weeks with progressively forceful, non-bilious, projectile vomiting immediately after feeding.
The diagnosis is often confirmed with an ultrasound, but the palpable 'olive' is the classic clinical sign.

Option A: An umbilical hernia presents as a soft, reducible bulge directly at the umbilicus (navel), not a firm, olive-shaped mass in the epigastrium.
Option B: Intussusception, the telescoping of one part of the intestine into another, classically presents with a 'sausage-shaped' mass, not an olive-shaped one.
Option D: A Wilms' tumor (nephroblastoma) is a kidney cancer that presents as a large, firm flank mass. Importantly, routine or vigorous palpation is contraindicated as it can cause the tumor to rupture, leading to metastasis.

Clinical Relevance

Nursing practice connection: Knowing Differential diagnosis of pediatric abdominal masses based on palpation findings helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Recognizing the 'olive' sign is a critical assessment skill for nurses, as it strongly suggests hypertrophic pyloric stenosis and requires prompt referral for surgical evaluation.
A key nursing priority is managing pre-operative dehydration and electrolyte imbalances (specifically hypochloremic, hypokalemic metabolic alkalosis) resulting from persistent vomiting.
Patient and family education is crucial regarding the need for surgery (pyloromyotomy) and post-operative care, including the reintroduction of feedings.

How to Approach the Question

First, identify the key clinical sign described in the question: a palpable 'olive-shaped mass' in the epigastrium.
Second, recognize that an 'olive-shaped' mass is a classic, pathognomonic sign for a specific pediatric gastrointestinal condition.
Third, evaluate the options based on your knowledge of pediatric abdominal pathologies.
Eliminate Umbilical Hernia, as it is a soft bulge at the navel.
Eliminate Intussusception, as its characteristic sign is a 'sausage-shaped' mass.
Eliminate Wilms' tumor, which is a flank mass where palpation is generally avoided.

Concept Tested & Keywords

Concept Tested: Differential diagnosis of pediatric abdominal masses based on palpation findings.
Stem keywords: palpation, olive-shaped mass, epigastrium, right of the midline
Lead-in keywords: indicative of

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E6 Nelson Textbook of Pediatrics(2024) — Volume 2 pp. 58-60, 936-938

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