Final answer:
The signs and symptoms of Hirschsprung disease include constipation, abdominal distention, and failure to thrive, as it affects the nerve cells in the colon leading to bowel blockage.
Step-by-step explanation:
The signs and symptoms of Hirschsprung disease, also known as megacolon, are constipation, abdominal distention, and failure to thrive. These occur because of the absence of nerve cells in a segment of the colon, which causes severe blockage and an inability to pass stool. Hirschsprung disease mainly affects infants and young children, resulting in a distended abdomen, difficulties with bowel movements, and insufficient weight gain due to the condition's interference with nutrient absorption and overall growth.