Hirschsprung Disease

Question 1

Who does Hirschsprung disease mainly affect?

Answer 1

Higher incidence occurs in boys

Question 2

How common is Hirschsprung disease?

Answer 2

~1/5000 live births

Question 3

What kind of problem is Hirschsprung disease?

Answer 3

Genetic problem (defective gene)

Question 4

What is the etiology of Hirschsprung disease (Briefly explain)?

Answer 4

• RET (proto-oncogene) gene mutation on chromosome 10. This gene is responsible for cell signalling. The gene codes for proteins that produce mediators to deliver information about cellular structures, esp neural cells. (this gene is important in embryogenesis)

Question 5

What occurs in adults if there is a RET gene mutation on Chr 10?

Answer 5

The mutations increase divisions -> can give rise to a tumor

Question 6

What occurs in infants if there is a RET gene mutation on Chr 10?

Answer 6

the mutation impedes development, more specifically in neuro cells

Question 7

What is the pathology behind Hirschsprung disease?

Answer 7

The colon requires specialized neuronal cells to initiate peristalsis, but if this gene is mutated, then parts of the colon will lack the parasympathetic ganglia (neural cells) and will not be able to perform peristalsis.

Content within the colon without parasympathetic ganglia will not be able to move forward at the affected areas -> no peristalsis at site -> accumulation of content -> colon distention -> abdominal distention

Question 8

What is a potential complication of Hirschsprung disease?

Answer 8

Rupture of the colon

Question 9

Treatment for Hirschsprung disease?

Answer 9

Aganglionic segment removal

Question 10

Aganglionic segment removal?

Answer 10

Surgically remove the area of the colon without ganglia and then anastomose the two ends of the unaffected colon.