Can Diverticulosis Cause Blood In Urine? | What It May Mean

No, diverticular pouches in the colon do not usually cause blood in urine; that finding points to a urinary issue or, in rare cases, a bowel-to-bladder fistula.

Seeing blood in your urine can rattle anyone. If you also have diverticulosis, it’s easy to connect the two and assume the colon is the source. In most cases, that link does not hold up. Diverticulosis affects the colon. Blood in urine, also called hematuria, usually starts somewhere in the urinary tract.

That said, there is one rare way bowel disease can show up in urine problems. When diverticular disease turns into diverticulitis and then causes a fistula between the colon and the bladder, urine symptoms can show up. Even then, blood in urine is not the usual headline symptom. Recurrent urinary tract infections, air in the urine, foul-smelling urine, or cloudy urine tend to stand out more.

This article lays out when diverticulosis is unlikely to be the reason, when diverticular disease can be part of the story, and what signs mean you should get checked soon.

What Diverticulosis Usually Does And Does Not Do

Diverticulosis means small pouches have formed in the wall of the colon. Many people have it and never know it. When it causes trouble, the symptoms usually stay in the digestive tract. Think belly pain, bloating, constipation, diarrhea, or blood in the stool. That pattern fits the colon. It does not fit urine.

When those pouches become inflamed or infected, the problem shifts into diverticulitis. That can bring steady belly pain, fever, nausea, and tenderness, often on the lower left side. If the inflammation gets bad enough, nearby organs can get pulled into the mess. That is where urine symptoms enter the picture.

According to the NIDDK page on diverticular disease, diverticulosis involves pouches in the colon, while symptoms, inflammation, bleeding, or complications fall under diverticular disease. The NHS also lists fistula formation as a rare complication of diverticulitis, including an opening from the bowel to the bladder.

Can Diverticulosis Cause Blood In Urine? Only In Rare Situations

Plain diverticulosis on its own is not a usual cause of hematuria. If blood shows up in the urine, doctors tend to think first about a urinary source: infection, stones, kidney disease, bladder irritation, enlarged prostate, or cancer.

The rare exception is a complication tied to diverticulitis, not simple diverticulosis. If an inflamed section of colon sticks to the bladder and a passage forms between them, that is called a colovesical fistula. Once that happens, bacteria and gas from the colon can enter the bladder. That can trigger repeated infections and other odd urine symptoms.

Even in that setting, visible blood in urine is not the main clue. The bigger clues are often:

• Repeated urinary tract infections that keep coming back
• Air bubbles in urine
• Cloudy or foul-smelling urine
• Pain when passing urine
• Lower belly pain with fever
• Urine symptoms that start during or after a diverticulitis flare

So the short clinical answer is straightforward: diverticulosis itself usually does not cause blood in urine. A rare fistula linked to diverticulitis can bring urinary symptoms, and blood may be part of that picture, but it is not the usual first sign.

Blood In Urine With Diverticulosis: What Often Fits Better

Blood in urine has a long list of causes, and many of them are more common than a bowel-bladder fistula. That matters because the right next step depends on the source. If you pin everything on diverticulosis, you could miss a bladder stone, kidney stone, infection, or another urinary problem that needs prompt care.

The NIDDK overview of hematuria notes that blood in urine can come from many conditions and should be worked up based on the full picture. That is why doctors usually ask whether the blood is visible, whether pain is present, whether there is fever, and whether you also have urinary urgency, burning, flank pain, or clots.

These clues can steer the first round of testing.

What you notice	More likely source	What it may point to
Burning, urgency, frequent peeing	Bladder or urinary tract	Urinary tract infection
Sharp side or back pain	Kidney or ureter	Kidney stone
Blood with no pain	Urinary tract	Needs evaluation for bladder, kidney, or prostate causes
Air bubbles in urine	Bladder linked to bowel	Possible colovesical fistula
Cloudy, foul-smelling urine with belly pain	Bladder plus nearby bowel inflammation	Infection or fistula
Fever with lower left belly pain	Colon first, bladder second	Diverticulitis with a possible complication
Blood in stool, not urine	Colon	Diverticular bleeding or another bowel source
Microscopic blood found on a urine test	Urinary tract	Needs follow-up if it does not clear

When Diverticular Disease Can Affect The Bladder

Diverticulitis can irritate nearby tissue. The bladder sits close to the colon, so repeated inflammation can make the two surfaces stick together. Over time, a tiny passage can form. Once that happens, colon bacteria can spill into the bladder and trigger a stubborn cycle of infection.

The NHS page on diverticular disease and diverticulitis lists a fistula to the bladder as a rare complication. That lines up with how doctors think about it in practice: rare, but real, and more tied to diverticulitis than to quiet diverticulosis.

If that complication is in play, the pattern often feels off. A person may get antibiotics for a urinary tract infection, feel better for a bit, then get another infection soon after. Or they may notice a strange smell to the urine, bits of debris, or air bubbles. Blood can happen, though it is not the sign doctors lean on most.

That is why the wording matters. Asking whether diverticulosis can cause blood in urine is not quite the same as asking whether diverticular disease can lead to urinary trouble. The first answer is usually no. The second answer is yes, in a small slice of complicated cases.

What Doctors Usually Check Next

Blood in urine should not be brushed off, even if it happens once. A workup often starts with a urine test and a history of your symptoms. Your clinician may ask when the blood started, whether it comes with pain, whether you have had stones before, and whether recent belly pain fits a diverticulitis flare.

If a fistula is on the list, a CT scan of the abdomen and pelvis is often the scan doctors reach for. If the focus is the urinary tract itself, the workup may also include imaging of the kidneys and bladder, urine culture, and at times cystoscopy, where a small camera looks inside the bladder.

Test	What it checks	Why it may be ordered
Urinalysis	Blood, white cells, bacteria, protein	Shows whether bleeding or infection is present
Urine culture	Bacterial growth	Looks for a urinary tract infection
Blood tests	Infection markers, kidney function	Checks how sick you are and whether kidneys are involved
CT scan	Colon, bladder, stones, fistula, abscess	Helps sort out diverticulitis and urinary causes
Cystoscopy	Inside of the bladder	Looks for bladder lesions, bleeding sites, or fistula clues

Signs That Mean You Should Get Checked Soon

Visible blood in urine should get medical attention. The same goes for urine that looks tea-colored, pink, or red. If you also have fever, chills, vomiting, back pain, or steady lower belly pain, the urgency goes up.

Get prompt care if you have any of these:

• Blood in urine that you can see
• Blood clots in the urine
• Fever with belly pain or burning urine
• Repeated urinary tract infections over a short span
• Air in the urine
• Trouble passing urine
• Dizziness, weakness, or fainting

If your pain is severe, you cannot keep fluids down, or you feel acutely unwell, urgent care is the safer move.

What The Takeaway Looks Like In Real Life

If you have known diverticulosis and notice blood in urine, do not assume the colon is to blame. Most of the time, the source sits in the urinary tract, not the bowel. That means the next step is not guesswork. It is a proper medical check.

The rare bowel-based exception usually involves diverticulitis with a fistula to the bladder. When that happens, the story often includes repeated infections, foul-smelling urine, air bubbles in urine, belly pain, or fever. Blood may show up, but it is only one piece of the puzzle.

So yes, there is a narrow path where diverticular disease can be tied to urine symptoms. No, plain diverticulosis is not a usual cause of blood in urine. That distinction can save time and get you to the right workup sooner.