A newborn is presented with a bloated abdomen shortly after birth with passing of less meconium. A full thickness biopsy of the rectum was carried out. Which one of the Following rectal biopsy findings is most likely to be present?

1. A

   Thickened Muscularis propria

2. B

   Hyalinization of the muscular coat

3. C

   Lack of ganglion cells

4. D

   Fibrosis of submucosa

Appeared in: JODHPUR AIIMS SNO-2018

Explanation

• The clinical scenario of a newborn with abdominal distension and delayed meconium passage strongly points towards Hirschsprung's disease.
• Hirschsprung's disease is defined by the congenital absence of ganglion cells (aganglionosis) in the distal bowel wall.
• These ganglion cells form the submucosal (Meissner) and myenteric (Auerbach) plexuses, which are essential for coordinating peristalsis and allowing the bowel to relax.
• Their absence leads to a functional obstruction, as the affected segment remains constricted.
• Therefore, a full-thickness rectal biopsy confirming the 'lack of ganglion cells' is the definitive diagnostic finding.

Why Other Options Were Wrong

• Option A: Thickening of the muscularis propria is a secondary change that occurs in the healthy, innervated bowel proximal to the aganglionic segment. It hypertrophies from working against the obstruction, but it is not the primary defect.
• Option B: Hyalinization, or the formation of a glassy, acellular material, is not a characteristic histological feature of Hirschsprung's disease. It is more associated with chronic inflammation or aging processes in other tissues.
• Option D: While some degree of inflammation and subsequent fibrosis can occur due to stasis and potential enterocolitis, it is a non-specific finding and not the primary diagnostic criterion for Hirschsprung's disease.

Related Visual

Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Diagnosis of Hirschsprung's disease via rectal biopsy as background academic context rather than a clinical decision trigger.
• A key nursing responsibility is to monitor and document the passage of meconium in all newborns. Failure to pass meconium within 24-48 hours is a red flag that must be reported to the physician.
• Nurses provide critical pre- and post-operative care for infants undergoing corrective surgery (e.g., a pull-through procedure), including ostomy care, nutritional support, and monitoring for complications like enterocolitis.
• Patient and family education is vital. Nurses teach parents how to care for their child post-surgery, including signs of complications and long-term bowel management strategies.

How to Approach the Question

• First, analyze the patient's profile and symptoms: a newborn with a bloated abdomen and minimal meconium passage.
• Recognize this combination as the classic presentation for a neonatal bowel obstruction.
• Recall common causes of neonatal bowel obstruction, with Hirschsprung's disease being a primary differential.
• Connect the symptoms to the underlying pathophysiology of Hirschsprung's: a segment of the bowel lacks the nerve (ganglion) cells needed for peristalsis, causing a blockage.
• Understand that the definitive diagnostic test is a rectal biopsy to look for these specific cells.
• Evaluate the options to identify the pathognomonic (conclusively diagnostic) histological finding, which is the absence of ganglion cells.

Concept Tested & Keywords

• Concept Tested: Diagnosis of Hirschsprung's disease via rectal biopsy.
• Stem keywords: newborn, bloated abdomen, less meconium, rectal biopsy
• Lead-in keywords: most likely
• Clinical cues: The combination of a newborn with a bloated abdomen and delayed passage of meconium is a classic presentation for Hirschsprung's disease.
• Negative lead-in flag: false

Question ID

Qbw1l1vAn7w3KF2IHg8hEm

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Reference Book

E6 Pathology-Textbook of PATHOLOGYHarsh Mohan Part 3 (515-969) p. 62-64

E6 Pathology- ROBBINS & COTRAN PATHOLOGIC BASIS OF DISEASE 10TH Ed p. 757-759

E6 Nelson Textbook of Pediatrics(2024) — Volume 2 p. 76-78