Adult-Gerontology Clinical Nurse Specialist (CNS) Practice Exam

Which of the following is an organic cause of constipation?

1. Hirschsprung's disease

2. Hypokalemia

3. Anorexia nervosa

4. Spinal cord lesions

The correct answer is: Hirschsprung's disease

Hirschsprung's disease is an organic cause of constipation because it is a congenital condition characterized by the absence of ganglion cells in the intestinal wall, particularly in the rectum and colon. This leads to impaired motility in the affected segments of the bowel, resulting in constipation due to the inability to properly move stool through the colon. The lack of ganglion cells means that peristalsis cannot occur effectively, which is essential for normal bowel movements. Understanding the nature of Hirschsprung's disease highlights its direct anatomical and physiological impact on bowel function, differentiating it from other causes of constipation, which may be functional or secondary to other conditions. For instance, hypokalemia and anorexia nervosa can contribute to constipation through metabolic and behavioral mechanisms, while spinal cord lesions may interfere with nerve signals that encourage bowel motility, but they are not inherently structural conditions affecting the bowel like Hirschsprung's disease.