Why you might need colorectal surgery

While most bowel symptoms aren’t severe and often resolve on their own, there are a few (think blood in stool) that could indicate more serious issues. DR RONNIE MATHEW, Medical Director and Senior Consultant at Colorectal Care Specialists, specialises in colorectal surgery in Singapore. Here, he outlines three symptoms that would need investigating, and where to go for colonoscopy and initial consultation.

When you might need colorectal surgery or a colonoscopy

#1 Change from usual bowel habit

If you’ve noticed a recent shift in how you pass stool, it’s worth getting your gut checked out. “This could be diarrhoea or loose stools, constipation or harder stools, or any changes in the frequency of bowel movements or the calibre of the stools (thinner or pellet-like stools),” explains Dr Mathew. He notes that if the symptoms are short-lived, they may be due to an infection, transient inflammation or other less serious causes.

“However, if there are persistent symptoms in the recent past, this is a more worrying sign. You should seek medical attention and may need colorectal surgery.”

#2 Blood in stool

Seeing blood in your stool is another thing that shouldn’t be casually brushed off. While it may be caused by something like haemorrhoids, it can also be a symptom of more serious disease like colorectal cancer.

“The colour of the blood in stool can vary from bright red to altered, darker blood or very dark, black stools,” Dr Mathew elaborates. “The colour of the stools usually gives a clue as to the site of the bleed. For example, the source of altered blood is likely to be from higher up in the colon rather than the rectum or anus.”

In addition to the colour, Dr Mathew says to pay attention to whether the bleeding is painful. “Painful or painless bleeding can indicate different things.”

#3 Unexplained weight loss

Losing weight without trying? “Weight loss, especially unintentional – as opposed to planned through dieting or exercise – needs to be taken seriously,” warns Dr Mathew. “It’s concerning when this is associated with either of the above symptoms or fatigue (which can be due to anaemia).”

Who’s more likely to require a colorectal procedure or surgery?

In addition to the above symptoms, Dr Mathew warns that individuals with the following risk factors should be particularly vigilant:

• People aged 45 and above with any bowel issues, particularly the three symptoms above.
• Those with a previous history of higher-risk polyps, inflammatory bowel disease (ulcerative colitis or Crohn’s) or who are immunosuppressed.
• Those with a family history of colorectal cancer, especially if affected family members were diagnosed before age 55 or if more than one family member is affected, regardless of their age.

Dr Mathew also warns that colorectal cancer often doesn’t show symptoms until it’s advanced. So, if there’s any concern, it’s best to get it checked by a colorectal specialist early before colorectal surgery becomes necessary.

Diagnosis and colorectal surgery in Singapore

For those experiencing any of the issues listed above, Dr Mathew recommends a thorough review and assessment. This usually includes blood tests and a colonoscopy in Singapore. Polyps found during a colonoscopy can typically be removed at the same time, avoiding the need for additional procedures. Any suspicious lesions should be biopsied. If concerns persist, further scans beyond a colonoscopy such as CT or MRI might be necessary. In some cases, colorectal surgery may be considered.

About the doctor

Dr Ronnie Mathew is a Senior Consultant Surgeon with almost three decades of surgical experience. He has a sub-specialty interest in colorectal surgery and is a keen advocate for minimally invasive surgery, especially robotic surgery.

Colorectal Care Specialists (CRCS) is at #14-15 Mount Elizabeth Medical Centre, 3 Mount Elizabeth.
6738 0328 | WhatsApp 9725 2381 | thecrcs.com

This article on indications like blood in your stool that you might need a colonoscopy and colorectal surgery in Singapore first appeared in the August 2025 edition of Expat Living. You can purchase the latest issue or subscribe so you never miss a copy.

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