What is intestinal pseudo-obstruction?

Intestinal pseudo-obstruction is a medical condition characterised by symptoms that resemble those of a true mechanical obstruction of the intestines, but without any actual physical blockage. Instead, the issue lies in the impaired motility (movement) of the intestines, which prevents the propulsion of food, fluids, and gas through the digestive tract.

Intestinal pseudo-obstruction can be classified into primary or secondary forms:

• Primary (idiopathic) intestinal pseudo-obstruction: This form has no identifiable underlying cause and is often considered a disorder of the enteric nervous system or the muscles of the gastrointestinal tract.
• Secondary intestinal pseudo-obstruction: This form is associated with a wide range of underlying medical conditions or external factors that affect the normal motility of the intestines. These include neurological disorders, connective tissue diseases, metabolic and endocrine disorders, and infections.

Intestinal pseudo-obstruction can be classified further into chronic or acute forms:

• Chronic intestinal pseudo-obstruction (CIPO): A long-term, often progressive form of the condition that leads to recurrent symptoms and can result in significant complications like malnutrition and chronic pain.
• Acute colonic pseudo-obstruction (Ogilvie's syndrome): A sudden and severe dilation of the colon without a mechanical cause, often occurring in hospitalised or critically-ill patients. This form requires immediate medical attention to prevent complications such as perforation.

What are the symptoms of intestinal pseudo-obstruction?

The symptoms of intestinal pseudo-obstruction can vary in severity and frequency, often mimicking those of a true mechanical bowel obstruction.

The most common symptoms include:

• abdominal pain or cramping
• bloating and a swollen abdomen
• nausea and vomiting
• constipation
• diarrhoea
• feeling full after eating small amounts of food
• weight loss and nutritional deficiencies, with chronic cases

How is intestinal pseudo-obstruction diagnosed?

The diagnosis of intestinal pseudo-obstruction involves a combination of:

• Medical history review, symptom assessment and a physical examination of the abdomen.
• Laboratory tests: These include blood tests to assess for signs of inflammation and metabolic disorders, as well as stool tests to rule out infectious causes of gastrointestinal symptoms.
• Imaging studies: These include abdominal X-rays to look for signs of obstruction, CT scans to identify any structural abnormalities, and MRI scans to evaluate gastrointestinal motility.
• Specialised tests for intestinal motility: These include gastric emptying study, small bowel transit study, colonic transit study, anorectal manometry, and antroduodenal manometry tests.
• Endoscopic biopsy to assess for underlying inflammatory or neuropathic changes.

It's essential to differentiate intestinal pseudo-obstruction from other conditions that can cause similar symptoms, such as mechanical bowel obstruction, inflammatory bowel disease (IBD), and functional gastrointestinal disorders like irritable bowel syndrome (IBS).

What treatments are available for intestinal pseudo-obstruction?

Treatment for intestinal pseudo-obstruction aims to alleviate symptoms, improve intestinal motility, manage complications, and address any underlying causes or contributing factors. The choice of treatment depends on the specific needs and circumstances of each patient, and treatment plans may need to be adjusted over time based on response to therapy and disease progression.

The main treatment options available include:

Medications

• Prokinetic agents: To stimulate intestinal contractions to improve motility, such as metoclopramide or erythromycin.
• Antibiotics: To treat bacterial overgrowth in the intestines, which can exacerbate symptoms.
• Antispasmodic agents: To relieve abdominal pain and cramping, such as dicyclomine or hyoscyamine.
• Analgesics: To manage severe abdominal pain.

Nutritional support

• Dietary changes: Adjustments to the diet, such as eating smaller, more frequent meals, avoiding foods that exacerbate symptoms (for example, high-fibre foods), and ensuring adequate fluid intake.
• Nasogastric decompression: Insertion of a nasogastric tube to remove gas and fluids from the stomach and intestines, relieving distension and discomfort.

Surgical Interventions

• Gastric electrical stimulation: Placement of a device that delivers electrical impulses to the stomach to regulate motility and reduce symptoms.
• Rectal tube placement: In some cases, a rectal tube may be used to decompress the colon and relieve symptoms of colonic pseudo-obstruction.
• Partial colectomy: Removal of a portion of the colon may be necessary in cases of severe colonic pseudo-obstruction or when other treatments fail.

Can intestinal pseudo-obstruction be cured?

While there is currently no cure for intestinal pseudo-obstruction, advances in medical understanding and treatment options continue to improve the prognosis and quality of life for affected patients. With appropriate management, symptoms can be controlled, and patients can lead fulfilling lives.