Chronic Intestinal Pseudo-Obstruction (CIPO)

What happens in CIPO

Normal gut movement (peristalsis) depends on three components working together:

• enteric nerves, the gut's own nervous system
• smooth muscle in the gut wall
• interstitial cells of Cajal, the gut's pacemaker cells

In CIPO, one or more of these fails, so contents stall. The bowel stretches, fluid and gas collect, and bacteria overgrow in the small intestine. CIPO can affect any part of the gut but usually involves the small intestine.

Types and causes

Primary (idiopathic or genetic) CIPO

No underlying disease is found. Some cases are present at birth or in early childhood, sometimes with bladder involvement (megacystis). Genetic forms include FLNA and ACTG2 gene variants and mitochondrial disorders such as MNGIE.

Secondary CIPO

CIPO develops as a complication of another condition:

Symptoms

• bloating and visible abdominal distension, often worsening through the day
• crampy or constant belly pain
• nausea and vomiting
• constipation, or diarrhea from bacterial overgrowth
• early fullness and reduced appetite
• weight loss and malnutrition
• urinary symptoms if the bladder is also involved

Symptoms often come in flares that look exactly like a bowel obstruction, separated by calmer periods.

Diagnosis

CIPO is often diagnosed late, after several emergency admissions and sometimes unnecessary surgeries. Diagnosis involves:

1. Ruling out a real blockage: CT or MR enterography shows dilated loops of bowel with fluid levels but no blocking point.
2. Blood tests: nutrition (albumin, vitamins, iron), electrolytes, thyroid function, autoimmune antibodies, and tests for diabetes, paraneoplastic antibodies and mitochondrial disease.
3. Motility testing: antroduodenal or small bowel manometry measures contraction patterns and can distinguish nerve from muscle disease. Gastric emptying studies and wireless motility capsules help map affected regions.
4. Breath testing or small bowel aspirate for small intestinal bacterial overgrowth.
5. Full-thickness bowel biopsy: obtained during surgery that is needed for another reason, to examine nerves, muscle and pacemaker cells.

Treatment

There is no cure for primary CIPO, so treatment aims to maintain nutrition, control symptoms and prevent complications. Care is best coordinated by a specialist motility center.

Nutrition

• Oral diet: small, frequent, low-fat, low-fiber meals; liquid or blended foods are easier to move.
• Enteral feeding: a tube into the stomach or small intestine if oral intake is not enough.
• Parenteral nutrition (IV feeding): for people who cannot absorb enough through the gut. It is lifesaving but carries risks of line infections and liver disease.

Medicines

• Prokinetics: prucalopride, metoclopramide, erythromycin, pyridostigmine or octreotide to stimulate gut movement.
• Antibiotics: rotating courses for bacterial overgrowth.
• Anti-nausea medicines.
• Pain management: avoiding opioids as far as possible because they worsen motility.
• Treating the underlying disease in secondary CIPO.
• Stopping causative medicines.

Procedures

• Venting gastrostomy or jejunostomy: a tube to release gas and fluid, easing distension and vomiting.
• Decompression with a nasogastric tube during flares.
• Surgery: limited resections or ostomies in carefully selected patients. Unnecessary operations should be avoided, as they create adhesions that make diagnosis and treatment harder.
• Intestinal transplant: for people with intestinal failure who develop serious complications of parenteral nutrition.

Outlook

Outlook varies widely. Some secondary forms improve when the underlying cause is treated. Primary CIPO is usually lifelong. Many people live for years with nutrition support and symptom management, but quality of life can be significantly affected, and psychological support is important.

Frequently asked questions

What is chronic intestinal pseudo-obstruction?

CIPO is a rare disorder in which damaged nerves or muscles in the intestinal wall cannot move food along properly. It causes repeated symptoms of bowel blockage, such as bloating, distension, pain and vomiting, even though no physical blockage is present.

What is the difference between bowel obstruction and pseudo-obstruction?

A bowel obstruction is a physical blockage from adhesions, a hernia, a tumor or twisting, often needing surgery. Pseudo-obstruction causes the same symptoms because the bowel cannot contract properly, but scans show no blockage. Surgery usually does not help pseudo-obstruction.

What causes CIPO?

CIPO can be primary, from genetic or unknown damage to gut nerves, muscle or pacemaker cells, or secondary to conditions such as scleroderma, diabetes, Parkinson's disease, amyloidosis, mitochondrial disease, some cancers and medicines like opioids.

How is CIPO treated?

Treatment focuses on nutrition (special diets, feeding tubes or IV nutrition), medicines to stimulate gut movement and treat bacterial overgrowth, venting tubes to relieve distension, and treating any underlying cause. Intestinal transplant is an option for severe cases.

Is CIPO the same as Ogilvie syndrome?

No. Ogilvie syndrome is acute colonic pseudo-obstruction, a sudden, short-term dilation of the colon, usually in hospitalized patients after surgery or illness. CIPO is chronic and recurrent and usually affects the small intestine.