Hirschsprung disease passmed Flashcards
What causes Hirschsprung’s disease and its prevalence?
Hirschsprung’s disease is caused by an aganglionic segment of bowel due to the developmental failure of the parasympathetic Auerbach and Meissner plexuses, occurring in about 1 in 5,000 births.
What is the pathophysiology of Hirschsprung’s disease?
In Hirschsprung’s disease, parasympathetic neuroblasts fail to migrate from the neural crest to the distal colon, resulting in developmental failure of the plexuses and leading to uncoordinated peristalsis and functional obstruction.
What are common associations of Hirschsprung’s disease?
Hirschsprung’s disease is three times more common in males and is associated with Down’s syndrome.
What are possible presentations of Hirschsprung’s disease in neonates and older children?
Possible presentations in neonates include failure or delay to pass meconium. In older children, it may present as constipation and abdominal distension.
What investigations are used for diagnosing Hirschsprung’s disease?
The main investigations for Hirschsprung’s disease are abdominal x-ray and rectal biopsy, with the biopsy being the gold standard for diagnosis.
What are the initial and definitive management strategies for Hirschsprung’s disease?
Initial management of Hirschsprung’s disease involves rectal washouts or bowel irrigation. Definitive management typically involves surgical removal of the affected bowel segment.
A 1-year-old boy presents with bilious vomiting, abdominal distension and has been constipated since birth and did not pass meconium until he was 3 days old. Height and weight are at the fifth percentile. On examination, the abdomen is distended and a PR examination causes stool ejection. What is the likely diagnosis?
Malrotation
Duodenal atresia
Hirschsprung disease
Pyloric stenosis
Intussusception
Hirschsprung disease
Hirschsprung disease is a congenital bowel disease, which is five times more likely to occur in boys than girls. It usually presents with bilious vomiting, abdominal distension, constipation and failure to pass meconium in the first 48 hours. Hirschsprung disease may not present until childhood or adolescence. Colon biopsy demonstrates an aganglionic segment of bowel.
A 2-year-old child has a history of chronic constipation for the past year and chronic abdominal distention with vomiting for three months. It is suspected that the child may have Hirschsprung’s disease. Which investigation from the list below offers the most definitive diagnosis for this condition?
Rectal biopsy
Anorectal manometry
Barium enema
Colonoscopy
Faecal elastase
Rectal biopsy
Rectal biopsy is the gold standard for diagnosis of Hirschsprung’s disease
Anorectal manometry can be helpful in the diagnosis of Hirschsprung’s though rectal biopsy remains the gold standard. This is because microscopic examination shows a lack of ganglionic nerve cells in the affected segment.
summarise hirschspring disease
Hirschsprung’s disease
Hirschsprung’s disease is caused by an aganglionic segment of bowel due to a developmental failure of the parasympathetic Auerbach and Meissner plexuses. Although rare (occurring in 1 in 5,000 births) it is an important differential diagnosis in childhood constipation.
Pathophysiology
parasympathetic neuroblasts fail to migrate from the neural crest to the distal colon → developmental failure of the parasympathetic Auerbach and Meissner plexuses → uncoordinated peristalsis → functional obstruction
Associations
3 times more common in males
Down’s syndrome
Possible presentations
neonatal period e.g. failure or delay to pass meconium
older children: constipation, abdominal distension
Investigations
abdominal x-ray
rectal biopsy: gold standard for diagnosis
Management
initially: rectal washouts/bowel irrigation
definitive management: surgery to affected segment of the colon
A 4-day-old girl who was diagnosed prenatally with Down’s syndrome and born at 38 weeks gestation presents with bilious vomiting and abdominal distension. She is yet to pass meconium.
What is the most likely diagnosis?
Duodenal atresia
Hirschprung’s disease
Intussusception
Necrotising enterocolitis
Pyloric stenosis
Hirschprung’s disease
Failure or delay to pass meconium is common presentation of Hirschprung’s disease
Hirschprung’s disease usually presents soon after birth with delayed passage of meconium, distended abdomen, bilious vomiting, lethargy and dehydration. It is associated with Down’s syndrome and is more common in males.
Pyloric stenosis will typically present with non-bilious projectile vomiting with a palpable epigastric mass on feeding.
Necrotising enterocolitis presents with vomiting, abdominal distention and blood in stools. Pre-maturity is a risk factor.
Intussusception typically presents between 3-12 months with colicky abdominal pain and drawing up of the infant’s legs. Blood in the stool is a late sign.
Duodenal atresia often shows up on antenatal screening. It presents with bilious vomiting hours after birth.
A 2-day-old baby has not passed meconium yet. Your consultant tells you they believe that the child has Hirschsprung’s disease, and asks you what your initial management would be. Until a firm diagnosis can be made and more definite treatment given, which of these is the best initial treatment for this child?
Anorectal Pull through
Bowel Irrigation
Full Thickness Rectal Biopsy
Lactulose
Vancomycin
Bowel Irrigation
The initial management in Hirschprung’s disease is rectal washouts/bowel irrigation
Important for meLess important
If Hirschsprung;s disease is suspected, a full thickness rectal biopsy should be performed as investigation. However, while this is being organised etc, bowel washouts should be performed to allow the baby to pass meconium, so this is the initial treatment. Once a diagnosis has been made, an anorectal pull through is generally performed as definitive management.
Anorectal pull through is the definitive management, not initial.
Bowel Irrigation/Rectal Washouts is the best initial treatment.
Rectal biopsy is used for diagnosis.
Lactulose is used for constipation in children but would be inappropriate in this case.
Vancomycin is inappropriate.
