Do I need surgery for diverticulitis?

Here is something that might put your mind at ease: around 75–85% of people who go to hospital with diverticulitis go home without needing any surgery at all. Most cases are treated with antibiotics, a rest from solid food, and some time for the bowel to settle down.

That said, some cases are more serious, and a smaller number of people are advised to have surgery — either urgently because of a complication, or as a planned operation to stop attacks from coming back. Understanding your options means you can have an informed conversation with your specialist about what is right for you.

Uncomplicated diverticulitis — managed at home: If your pain is mild, your temperature is only slightly raised, and a CT scan shows nothing alarming, you may be able to manage at home with oral antibiotics (usually for 5–7 days), clear fluids, and rest. You will need to follow up with your GP. Interestingly, some newer guidelines suggest that selected patients with mild cases may even recover without antibiotics — your doctor will guide you on this.

Uncomplicated diverticulitis — admitted to hospital: If the pain is more severe, your temperature is higher, you cannot keep fluids down, or the diagnosis is uncertain, you will be admitted to hospital for antibiotics and fluids through a drip, and you will be monitored closely. A CT scan will confirm what is happening and how serious it is. Most people settle down within 48–72 hours and go home with a course of oral antibiotics.

Complicated diverticulitis — abscess: An abscess is a pocket of pus that has formed next to the bowel. Small ones (under about 3–4 cm) often clear up with antibiotics alone. Larger ones usually need to be drained — a radiologist uses a scan to guide a small tube through your skin into the abscess to drain it. Surgery is needed if this approach does not work.

Complicated diverticulitis — perforation (peritonitis): If a diverticulum bursts and causes widespread infection inside the abdomen — called peritonitis — this is a surgical emergency. You will need an operation urgently to clean out the infection, remove the affected piece of bowel, and depending on circumstances, either create a temporary stoma (an opening from the bowel to the skin) or join the bowel back together at the same time.

Complicated diverticulitis — fistula: After repeated bouts of inflammation, an abnormal passage (called a fistula) can form between the bowel and a nearby organ — most commonly the bladder (which can cause air or faeces in the urine) or the vagina. Fistulas rarely heal on their own and usually need planned surgery to repair them.

Planned surgery for recurrent or ongoing diverticulitis: If you have had two or more serious attacks, if you have been troubled by ongoing pain between episodes, or if you have had a serious complication, your surgeon may recommend a planned (elective) operation — carried out once you have fully recovered from the last attack.

The decision to recommend surgery is made individually — it is always about weighing the risks of living with ongoing diverticulitis against the risks of having an operation. Surgery tends to be discussed when:

• You have had two or more episodes that needed hospital admission
• You have ongoing pain or symptoms between attacks — ongoing left-sided abdominal pain, changes to your bowel habit — that are affecting your quality of life
• You have had a serious complication such as an abscess or a fistula, even if it only happened once
• You are younger (under 50), which means you could face many more attacks over the years ahead
• Scans have not been able to completely rule out bowel cancer, and your colonoscopy results were not clear-cut
• You are on medications that suppress your immune system (such as steroids, chemotherapy, or anti-rejection drugs after a transplant), which makes future attacks more unpredictable and dangerous

One important thing to know: the old rule of "two episodes means surgery" has been updated. Today, your surgeon looks at the full picture — how severe your episodes have been, how they are affecting your life, your overall health, and what you want. It is a conversation, not a checklist.

For planned surgery, the standard operation is called a laparoscopic sigmoid colectomy — the surgeon removes the sigmoid colon (the part of the large bowel most commonly affected by diverticulitis) using small keyhole incisions. Once that section is removed, the two ends of the remaining bowel are joined back together (called an anastomosis), so your bowel works normally again.

In published series, the keyhole approach is associated with smaller cuts, less pain after the operation, and a faster recovery compared with open surgery. Most people stay in hospital for three to five days and are back to normal activities within four to six weeks.

In an emergency — for example, if a diverticulum has burst and caused widespread infection in the abdomen — a different operation called a Hartmann's procedure may be necessary. The diseased bowel is removed, the lower end is closed off, and the upper end is brought to the surface of the abdomen as a colostomy (a stoma — a small opening where a bag is worn). For many people, a second operation to reconnect the bowel and close the stoma is possible six to twelve months later, once everything has fully healed.

In some carefully chosen patients where the infection is less severe, it may be possible to join the bowel back together straight away during the emergency operation, avoiding a stoma altogether. Your surgeon will make this judgment based on your condition and the findings during the operation.

For an otherwise healthy person, planned keyhole surgery on the sigmoid colon is generally safe — but it is important to be honest that all surgery carries some risk. The main things your surgeon will talk to you about include:

• Anastomotic leak: This is when the join between the two ends of bowel does not heal properly and leaks. It happens in roughly 2–5% of cases and is a serious complication that may need further surgery.
• Bleeding: Heavy bleeding needing a transfusion or a return to theatre is uncommon but possible.
• Infection: Wound infections or an abscess inside the abdomen can occur.
• Injury to the ureter or bladder: The tube that carries urine from the kidney (the ureter) runs close to the sigmoid colon. Your surgeon will identify and protect it carefully, but an injury is possible though uncommon.
• Conversion to open surgery: If the keyhole approach is not safe due to scarring from previous episodes, the surgeon may need to make a larger incision.
• Changes to bowel habits: Most people find their bowels work normally after surgery. Loose stools in the first few weeks are common but usually settle.

Your surgeon will go through the risks that apply specifically to you — your age, your health, and how complicated your diverticular disease has been all factor into the conversation.

That is a valid choice. If you have had recurrent diverticulitis but do not want surgery — or if your overall health means surgery is not the safest option — the focus shifts to managing things conservatively: eating a high-fibre diet, keeping your weight healthy, avoiding anti-inflammatory painkillers like ibuprofen, and treating any future episodes early.

It helps to know the numbers: after a first attack, the risk of having another one is roughly 25–35%. Each episode does carry some risk of complications. But for many people — particularly older patients or those with other health conditions — the risks of an operation outweigh the benefits of having it, and conservative care is absolutely the right path. The most important thing is that you make this decision feeling well-informed and supported by your colorectal surgeon.

For most people who have planned surgery for diverticular disease, the result is durable relief — living without the constant pain, the anxiety of waiting for the next attack, and the dietary restrictions can make a meaningful difference to your everyday life. Your bowel function generally returns to normal within a few months.

After the operation, eating a high-fibre diet is still the best long-term strategy. The remaining colon still has diverticula in it — they cannot all be removed — so there is a small ongoing risk of diverticulitis there. Keeping up healthy habits matters, but most people find this easier to manage when the worst-affected part of the bowel has been removed.