Newborn with abdominal distension and failure to pass meconium

Gross pathological image of Hirschsprung disease
Gross pathological image of the recto-sigmoid colon shows the dilated proximal portion of sigmoid colon which contained ganglion cells (on the left) separated by a transition zone from the narrowed distal portion of rectum (on the right) which turned out to be aganglionic.

The diagnosis was Hirschsprung disease.