ACQUIRED megacolon in the adult sometimes progresses to an advanced stage characterized by anorexia, obstipation, bouts of abdominal pain and distention, weight loss, and extreme debility. These large decompensated colons function so poorly and the response to treatment is so unsatisfactory that management of this problem frequently becomes extremely difficult.
The term "megacolon" should be restricted to those patients who have large dilated colons associated with chronic constipation of long standing. Acquired megacolon (also referred to as functional or idiopathic megacolon) should exclude all cases of megacolon with known etiological factors such as aganglionic megacolon, obstructive lesions, megacolon of central nervous system origin, trypanosomiasis, myxedema, etc. This leaves a group of patients with acquired megacolon of rather obscure origin, probably the result of faulty bowel habits compounded by repeated laxation and enemiasis with psychogenic factors playing an unknown but important role. Attention recently has been focused on acquired megacolon in
WATKINS GL. Operative Treatment of Acquired Megacolon in Adults. Arch Surg. 1966;93(4):620-624. doi:10.1001/archsurg.1966.01330040084015