**Question:** Chronic constipation in children is seen in all EXCEPT:

A. Hirschsprung disease
B. Neurological disorders
C. Hypothyroidism
D. Psychological disorders

**Core Concept:** Chronic constipation is a gastrointestinal disorder characterized by infrequent bowel movements (less than 3 per week) with hard, difficult-to-pass stools, and sometimes abdominal pain, bloating, and decreased appetite. It can be caused by various factors, including anatomical, physiological, and psychological factors.

**Why the Correct Answer is Right:** Chronic constipation in Hirschsprung disease is incorrect because this condition is characterized by the absence of ganglion cells in the distal colon, leading to incomplete intestinal motility and constipation.

**Why Each Wrong Option is Incorrect:**

A. **Hirschsprung disease:** As mentioned above, this condition results in constipation due to ganglion cell absence in the distal colon.
B. **Neurological disorders:** Chronic constipation can be a symptom of neurological disorders, such as spinal cord injuries, spinal muscular atrophy, or cerebral palsy. These conditions generally do not exclude constipation in children.
C. **Hypothyroidism:** Hypothyroidism can cause constipation due to decreased intestinal motility and transit time. Hypothyroidism is not specific enough to exclude constipation in children with other causes.
D. **Psychological disorders:** Psychological factors can also contribute to chronic constipation through behavioral changes, such as reduced fluid intake, decreased appetite, and reduced bowel movements. Psychological disorders are not specific enough to exclude constipation in children with other causes.

**Clinical Pearl:** Chronic constipation in children should be evaluated for the underlying cause, as the provided options only account for a subset of the possible causes. It is essential for pediatricians and gastroenterologists to consider a comprehensive assessment involving medical history, physical examination, and investigations to determine the exact cause and appropriate management.