A colonscopy is done for small girl due to chronic constipation. they took biopsy , no polyp found. what is expected finding beside redundant colon?

Constipation: The biopsy was likely done to look at the nerve supply to her colon. There is a problem with the colon called Hirschsprung's disease where the patient has no ganglion or nerve cells of parts or the entire large intestine. The intestine is unable to function properly and causes constipation. If the innervation is normal, often years of constipation will cause weakness of muscles used for stooling.