Miscellaneous disorders of the bowel and liver

A wide range of miscellaneous disorders can affect the bowel and liver: some that are relatively common and of particular note are:

Microscopic colitis—characterized by the triad of watery diarrhoea, a normal macroscopic colonoscopy, and specific histology showing either a lymphocytic colitis or collagenous colitis. May resolve spontaneously, but treated with budesonide if it does not.

Intestinal pseudo-obstruction—acute massive dilatation of the caecum and colon can occur following intra-abdominal surgery or in any critically ill patient. Most patients have constant dull pain with marked abdominal distension and vomiting. The diagnosis is made on plain abdominal radiography. After exclusion of other causes of colonic dilatation, treatment is with nasogastric suction, intravenous fluids and electrolytes, and cessation of drugs that impair bowel motility.

Solitary rectal ulcer syndrome—caused in most cases by mucosal ischaemia and infarction and usually presents with bleeding per rectum, often leading to anaemia. Biopsy is required to rule out malignancy. Treatment is often difficult but requires correction of constipation with bulking agents and avoidance of straining at stool.

Ischaemic hepatopathy—diffuse hepatic injury can occur with acute reduction in hepatic blood flow, e.g. following shock. Blood tests demonstrate marked elevation of transaminases and prolongation of prothrombin time. There is no specific treatment.

Portal vein thrombosis—can be associated with a range of conditions, e.g. pancreatitis, abdominal surgery/malignancy, thrombophilic states. Often asymptomatic, but may present as haemorrhage from oesophageal or gastric varices. Diagnosis is made by Doppler ultrasonography, CT, or magnetic resonance angiography. Variceal band ligation or injection sclerotherapy may be required. Anticoagulation with warfarin reduces the risk of further thrombotic events in the splanchnic circulation and does not increase the risk of variceal haemorrhage.