Which condition can be indicated by meconium and sigmoid megacolon on imaging?

The presence of meconium along with sigmoid megacolon on imaging is indicative of Hirschsprung's disease. This condition, also known as congenital aganglionic megacolon, occurs when there is an absence of ganglion cells in the myenteric plexus of the colon. This absence leads to a lack of normal peristalsis in the affected segment, typically the rectum and extending proximally, causing an inability to relax and leading to a functional obstruction.

In Hirschsprung's disease, the distal colon can become massively dilated due to the accumulation of fecal material, causing the classic sign of megacolon. The meconium represents the built-up stool that the child is unable to pass due to the obstructed segment. Infants with this condition often present with delayed passage of meconium, abdominal distension, and constipation. This developmental defect becomes evident through imaging studies, which can show the characteristic findings of a dilated colon proximal to the obstruction.

In contrast, conditions like cystic fibrosis might lead to fecal impaction but not specifically to the classic sigmoid megacolon presentation seen in Hirschsprung's disease. Intestinal obstruction can present with different causes and is not necessarily associated with the specific