Q: I am a 20 years old boy having loose motions and sometimes constipation too. I have undergone colonoscopy, biopsy and CT scan, but all results were normal. My sugar and haemoglobin levels are also normal, but the study of barium enema reveals the presence of persistent narrowing in the proximal sigmoid colon, which does not distend even on double contrast study. Please advise.

A:Persistent narrowing in the proximal sigmoid needs further investigations. I note the colonoscopy was normal, which means there was no obvious pathology like a polyp or a tumour to be seen projecting into the lumen of the colon. This would mean the pathology could be in the wall of the sigmoid colon and therefore you need further colonoscopy and biopsies from the area of narrowing to exclude a pathology brewing in the wall of the sigmoid colon. After having mentioned this, sometimes similar feature of persistent narrowing can be noted rarely when no pathology can be identified and so regular follow up investigations would be warranted. Such features have been noted in pre-diverticular disease where irregular bowel habit is a common feature.