Colonic pseudo-obstruction

Colonic pseudo-obstruction (also known as Ogilvie syndrome) is a potentially fatal condition leading to an acute colonic distention without an underlying mechanical obstruction. It is defined as an acute pseudo-obstruction and dilatation of the colon in the absence of any mechanical obstruction.

Epidemiology

Numerous causes have been identified, and the demographics of affected patients generally reflect these, with elderly unwell patients being most frequently affected . Usually seen in people over 60 years of age and there is male predilection .

Clinical presentation

Patients usually present with constipation, nausea, vomiting and abdominal distension. Pseudo-obstruction can present with a sudden painless enlargement of the proximal colon accompanied by distension. Bowel sounds are normal or high-pitched, but should not be absent.

Despite the absence of mechanical obstruction, patients can nonetheless go on to bowel necrosis and perforation (especially if dilatation is severe) which in turn can go on to become generalized peritonitis .

Pathology

Pseudo-obstruction is related to decreased parasympathetic activity.

Risk factors include:

  • trauma
  • burns
  • recent surgery
  • medications 
    • opioids
    • phenothiazines
    • clozapine 
  • respiratory failure
  • electrolyte disturbances
  • diabetes mellitus
  • uremia

Radiographic features

Plain radiograph

Findings can be identical to a mechanical large bowel obstruction .

Fluoroscopy

A single contrast/water-soluble enema demonstrates the absence of any mechanical obstruction.

CT 

The hallmark of colonic pseudo-obstruction is the presence of dilatation of the large bowel (often marked) without evidence of an abrupt transition point or mechanically obstructing lesion.

It is important to note, however, that a gradual transition point is frequently present, usually at or near the splenic flexure .

Treatment and prognosis

Treatment involves correction of the underlying disorder and correction of any biochemical abnormalities. Medical treatment options include anticholinesterases like neostigmine and antibiotics like erythromycin.

Decompression with a rectal tube (endoscopic decompression) or careful colonoscopy may be effective . In severe cases, surgical or fluoroscopy-assisted cecostomy is necessary, or even occasionally a percutaneous endoscopic colostomy (PEC).

Complications
  • cecal perforation: decompression is usually undertaken if the caliber is more than 9-12 cm

History and etymology

It was initially described by the British general surgeon Sir W (William) Heneage Ogilvie (1887-1971) in 1948 .

Differential diagnosis

General imaging differential considerations include:

Siehe auch: