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Miscellaneous disorders of the bowel and liver 

Miscellaneous disorders of the bowel and liver

Chapter:
Miscellaneous disorders of the bowel and liver
Author(s):

Alexander Gimson

DOI:
10.1093/med/9780199204854.003.1526
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Essentials

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.

Microscopic colitis

This syndrome is characterized by the triad of watery diarrhoea, a normal macroscopic colonoscopy, and specific histology showing either a lymphocytic colitis or collagenous colitis. Although usually considered together as microscopic colitis there are some distinct epidemiological, histological, and therapeutic differences between the two types. There is an annual incidence rate of 10/100 000 with lymphocytic colitis being marginally the most common. It is five times more common over the age of 65 years and in women. There have been associations with coeliac disease, hypothyroidism, and a family history of inflammatory bowel disease.

Collagenous colitis

This was first recognized by Linstrom in 1976. Patients, mostly women, usually present in the fifth and sixth decade but the disease can occur in young adults as well as in older people. Watery diarrhoea accompanied by occasional abdominal cramps, wind, distension, and some nausea are usual. Diarrhoea can be severe and may seem secretory in nature. There may be some mucus, but bleeding per rectum does not occur. Despite such severe symptoms the patients look well, with a good appetite, and they do not lose weight. There are no abnormal physical signs and on colonoscopy the mucosa looks normal although it may seem somewhat granular and hyperaemic. Such endoscopic changes can occur throughout the colon but are usually patchy and never severe. The diagnosis is made on the appearance of the biopsy where there is a thickened band of subepithelial collagen extending 15 µm compared with a normal thickness of 2 to 6 µm. The collagen band is widest in the right colon and tends to become thinner more distally. Immunohistochemical studies have shown that the abnormal tissue consists predominantly of collagen type 3 and there is a patchy variable inflammatory infiltrate in the lamina propria consisting of lymphocytes, plasma cells, and some neutrophils. The disease is confined to the colon and is distinct from collagenous sprue.

Lymphocytic colitis

The clinical symptoms are similar to collagenous colitis but the mucosa always looks normal at colonoscopy. Histological examination shows a diffuse inflammatory cell infiltrate throughout the lamina propria with no architectural changes to the glands. The infiltrate is predominantly lymphocytes but there may also been eosinophils and a characteristic feature is the marked increase in intraepithelial lymphocytes, which clearly distinguishes it from ulcerative colitis where they are normal or reduced.

In some cases of microscopic colitis there may be spontaneous remissions and symptoms may have been preceded by some infectious trigger, including Campylobacter jejeuni, Clostridium difficile, or yersinia infection. In cases that do not resolve, treatment is now more rational as recent meta-analyses have demonstrated significant improvement with budesonide although there are also reports of improvements with mesalazine, cholestyramine, bismuth, or just simply with loperamide.

Complications of parenteral nutrition and intestinal failure

A number of complications of parenteral nutrition have been described relating to vascular thrombosis and catheter-related sepsis, but metabolic complications and the development of a cholestatic liver disease are the most important. Metabolic dysfunction includes hyperglycaemia, dyslipidaemia, manganese toxicity, oxalate renal stones, osteoporosis, and a refeeding syndrome which includes hypophosphataemia, hypernatraemia, and hypokalaemia shortly after starting nutrition in a malnourished patient. Hepatobiliary disease includes cholelithiasis and a progressive cholestasis resulting in liver failure. This progressive liver disease is more common in children with intestinal failure (due for instance to necrotizing enterocolitis) but may also occur in adults. In larger cohort studies about 25% of cases receiving total parenteral nutrition (TPN) will have significantly abnormal liver blood tests with up to 5% showing evidence of fibrosis leading to cirrhosis. The liver disease may be driven by the TPN itself and result from nutrient excess, deficiency, or toxicity, and is suggested by the dramatic improvements in liver function that can occur with manipulation of the contents of the nutrition support. On the other hand, it may also be related to the accompanying bowel resection. Bacterial overgrowth, increased permeability of the bowel wall due to intestinal atrophy, gut-derived endotoxins, and lithocolic acid with a reduced circulating bile salt pool and bile flow promoting cholestasis have all been suggested. The development of a similar liver disease in patients following a jejeuno-ileal bypass and other forms of bariatric surgery and the fact that liver dysfunction is less common in patients with an intact colon or who can maintain small amounts of enteral feeding are evidence in favour of the gut being a major driver of the liver pathology.

Management of these cases should be centralized in intestinal failure units experienced in the complex management of nutrition support and scrupulous catheter care. A careful balance in lipid composition, where both too much and too little must be avoided as well as too much carbohydrate, is important. Cyclical feeding and wherever possible maintaining at least some enteral nutrition are recommended. Ursodeoxycholic acid, as a choleretic, has been shown to prevent liver dysfunction and antibiotics to prevent bacterial overgrowth in children but there is less evidence of their efficacy in adults. Supplementation with choline and taurine are also important. Bowel-lengthening surgical techniques in children are still unproven but there is increasing evidence of the benefit of transplantation of the small bowel (with or without a liver) and 50% 5-year survival is now being recorded.

Miscellaneous vascular disorders of the intestine

Spontaneous intramural haemorrhage

Spontaneous bleeding into the bowel wall may occur following trauma; during excessive anticoagulation with warfarin; in patients with coagulation disorders, particularly haemophilia; and in vasculitis. It may present as pain, symptoms of partial intestinal obstruction, intussusception, and rarely intestinal haemorrhage. Diagnosis is best made by abdominal CT scan or barium radiology and treatment is usually conservative with correction of the coagulation deficit and transfusion.

Aorto-enteric fistulas

Aorto-enteric fistulas are rare but serious conditions that may arise as a complication following abdominal aortic surgery or rarely spontaneously. Clinical symptoms range from occult recurrent gastrointestinal bleeding and intermittent unexplained fever attacks to dramatic massive intestinal blood loss with shock. The fistula is usually in the second or third part of the duodenum and may be diagnosed by CT, angiography, or occasionally red cell scintigraphy. Treatment is by surgery although recently endoluminal aortic stents have been successfully used. Overall mortality remains high.

Vascular malformations; haemangiomas of the bowel

Angiodysplasia of the bowel is described in Chapter 15.4.2. Cavernous haemangiomas of the bowel are rare occurring most commonly in the rectosigmoid region. Some are found as a component of the blue rubber bleb nevus syndrome (Bean syndrome) associated with cutaneous haemangiomas. They present in young patients with iron deficiency anaemia. Diagnosis may be made by endoscopic examination, CT or MRI, and surgical resection of the lesions is necessary if the haemangiomas are associated with significant symptoms.

Miscellaneous vascular disorders of the liver

Congestive hepatopathy

The liver’s complex blood supply and high metabolic activity may be affected in a number of clinical situations when there is reduced splanchnic inflow and impaired hepatic venous outflow. Hepatic venous outflow obstruction and Budd–Chiari syndrome are dealt with in Chapter 15.22.3. Congestive hepatopathy may occur in the context of reduced cardiac output and high right-sided venous pressure, due to constrictive pericarditis, mitral stenosis, tricuspid regurgitation, and cardiomyopathy. The hepatic congestion and reduced liver sinusoidal perfusion is usually asymptomatic as the heart failure dominates the clinical scenario. There is an elevated jugular venous pressure, with ‘v’ waves in the presence of tricuspid regurgitation, hepatomegaly, and a positive hepatojugular reflex. The liver may be pulsatile when tricuspid regurgitation is severe. The consequent reduced sinusoidal blood flow can lead to ischaemia in zone 3 of the hepatic lobule and histological changes are characterized by centrilobular congestion with surrounding fatty change, initially described as the ‘nutmeg liver’. If the disorder is long-standing there may be progressive fibrosis extending peripherally from the centrilobular to the periportal areas although regenerative nodules are usually not present. A modestly elevated serum bilirubin level may be the only abnormality, with a normal serum alkaline phosphatase and elevated aminotransferases. Although minor changes in liver biochemistry are observed in cases with chronic biventricular heart failure, true cases of cardiac cirrhosis are very uncommon as are major complications from portal hypertension. Occasionally this situation is complicated by the presence together of an alcohol-induced liver injury and an alcoholic cardiomyopathy. In these circumstances it may be necessary to undertake histological examination of the liver as well as measuring right-sided cardiac pressures and free and wedged hepatic venous pressure gradients. The treatment for congestive hepatopathy centres on improving cardiac function with standard therapies.

Ischaemic hepatopathy

This refers to the diffuse hepatic injury that follows an acute reduction in hepatic blood flow. It may be due to any of the causes of sudden shock (haemorrhage, cardiac arrest, severe septic shock) but a similar syndrome has also been described in hepatic sickle cell crisis, following liver transplantation with hepatic artery thrombosis, and in severe respiratory failure and hypoxaemia. Histology shows a centrizonal necrosis and blood tests demonstrate marked elevation of transaminases, prolonged prothrombin time, and jaundice. The differential diagnosis includes other cause of sudden hepatocyte necrosis including drug hepatotoxicity and viral hepatitis. Rarely, acute liver failure with encephalopathy may develop in the most severe cases of ischaemic hepatopathy. There is no specific treatment for the liver dysfunction in this context, management being directed at the cause of the impaired hepatic perfusion.

Hepatic artery aneurysm

Hepatic artery aneurysms have been found in a number of conditions but are most common after surgery. They may also be found in the Osler–Weber–Rendu syndrome, Behçet’s syndrome, polyarteritis nodosa, and as part of systemic sepsis with fungal infection. It may be an incidental finding on an angiogram or present with pain, sometimes in the back and rarely after cholecystectomy with jaundice and biliary obstruction. Spontaneous rupture has been associated with haemobilia and is a major medical emergency presenting with severe abdominal pain and shock followed by jaundice. Treatment is with either hepatic artery embolization or surgery.

Portal vein thrombosis

Spontaneous thrombosis of the portal vein, although often asymptomatic, may cause a range of serious medical complications. A thrombosis may develop in one or more of the intrahepatic portal vein branches, or within the main portal vein itself and may involve the superior mesenteric or splenic veins which join to form the main trunk of the portal vein. Thrombosis may result from infection after birth arising in the umbilical vein, following acute pancreatitis (occasionally isolated to the splenic vein alone), surgery or abdominal trauma, as a complication of cirrhosis with or without an additional hepatocellular carcinoma, pancreatic and other intrabdominal malignancy, retroperitoneal fibrosis and a number of thrombophilic states. These include polycythaemia rubra vera, any cause of thrombocytosis, factor V Leiden and factor II (G20210A) deficiency, antithrombin III, protein C and S deficiency, paroxysmal nocturnal haemoglobinuria, and the lupus anticoagulant. Septic thrombosis of the portal vein may also occur associated with another infective focus within the abdomen such as acute appendicitis or diverticular disease. Often asymptomatic, it may present as haemorrhage from oesophageal or gastric varices and rarely with biliary obstruction from choledochal varices. The diagnosis can be made at Doppler ultrasound examination of the liver, CT or magnetic resonance angiography. When portal vein thrombosis presents with variceal haemorrhage endoscopic therapy with variceal band ligation or injection sclerotherapy is required. Occasionally surgical shunts can decompress the portal venous system, but this is often not possible due to the extensive nature of the thrombosis. Clot lysis is not possible as the thrombosis is usually long-standing. Anticoagulation with warfarin has been shown to reduce the risk of further thrombotic events in the splanchnic circulation and does not increase the risk of variceal haemorrhage.

Cystic disorders of the bowel

Colitis cystica profunda

First described by Stark in 1766 and then by Virchow as colitis cystica polyposa in 1863, the disorder is characterized by submucosal mucin-filled cysts. They may be single or multiple, within 12 cm of the anal verge, and are more common in younger men. It may represent a subgroup of the solitary rectal ulcer/rectal prolapse syndrome but has also been associated with Crohn’s disease. The cysts are seen at colonoscopy as a submucosal mass covered by normal rectal mucosa that may be occasionally hyperaemic, polypoid, or ulcerated. Diagnosis can be made with transrectal ultrasound, MRI, or colonoscopy, as it is important to exclude malignancy. Treatment is with bulking agents and laxative, re-education to avoid straining at stool, and surgery only if there is associated rectal prolapse.

Pneumatosis cystoides intestinalis

Gas-filled cysts within the small or large bowel are rare and can develop in a wide range of conditions. Some are primary, asymptomatic, often in the left colon and with no apparent cause. Others are secondary, involve the ileum and right colon, and can be associated with chronic obstructive pulmonary disease, intestinal obstruction, severe colonic inflammation (pseudomembranous colitis, necrotizing enterocolitis), connective tissue disease (systemic sclerosis, mixed connective tissue disease), amyloidosis, endoscopy, or CT colography. Pneumatosis cystoides intestinalis has recently been described in patients receiving α‎-glucosidase inhibitors. The submucosal or subserosal cysts are lined by histiocytes and giant cells and, although easy to diagnose on resection, specimens can be difficult with biopsies. Symptoms, where present, may include diarrhoea, vague abdominal discomfort, blood per rectum, and weight loss. The air-filled spaces may be seen on abdominal films but CT is best to diagnose them. They appear as submucosal masses on colonoscopy. Rarely portal venous gas can also be visualized, which implies associated bowel infarction. In some primary cases a conservative approach is possible but when symptomatic treatment is with high flow oxygen therapy 55 to 75% O2 aiming for a PaO2 greater than 200 mmHg for 4 to 10 days or, avoiding oxygen toxicity, with hyperbaric oxygen. If colonic integrity is compromised, or there is evidence of systemic sepsis or bowel perforation, broad spectrum antibiotics and surgery are required.

Disorders of the peritoneum

A number of rare disorders can specifically affect the peritoneum and serosal surfaces of the large and small bowel (Box 15.26.1). Their importance is firstly as a differential diagnosis for diffuse malignant infiltration of the peritoneum, by far the commonest cause of widespread peritoneal deposits seen on cross-sectional imaging, but also because they may require specific therapy.

Disseminated malignancy is common, with ovarian and adenocarcinoma most prevalent. Patients present with abdominal swelling, ascites, pain, and weight loss. CT scanning will reveal peritoneal deposits and biopsy is mandatory in order to tailor chemotherapy to specific cancers. Primary peritoneal mesothelioma presents in a similar manner with a slightly better prognosis. Peritoneal carcinomatosis is associated with poor survival and reduced quality of life, but a significant improvement in survival has recently been associated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with disseminated ovarian and gastric cancer and peritoneal mesothelioma.

Desmoid tumours (aggressive fibromatosis) are rare benign neoplasms of fibroblastic origin, that can be either extra- or intra-abdominal (mesenteric fibromatosis). They are locally invasive, with high recurrence rates. It occurs as a sporadic form and associated with familial neoplastic syndromes including Gardner’s syndrome and familial adenomatous polyposis (FAP). Sporadic cases may have mutations in the adenomatous polyposis coli (APC) or β‎-catenin (CTNNB1) genes. In FAP, tumours carry biallelic APC mutations. Overall desmoids can occur in up to 15% of FAP cases rising to 65% after abdominal surgery in those with 3′‎ APC mutations. They are a leading cause of death after colectomy. Symptoms include pain, features of intestinal obstruction, and often a palpable mass. Treatment remains unsatisfactory and includes surgery, nonsteroidal anti-inflammatory drugs, and tamoxifen.

Pseudomyxoma peritonei has been linked to peritoneal spread of appendiceal and ovarian mucinous tumours.

Erdheim–Chester disease is a multisystem xanthomatosis with histiocytic proliferation similar to Langerhans cell histiocytosis but with a different immunohistochemical profile. Sheets of foamy histiocytes can involve lung, skin, brain, adrenals, renal tract, liver and peritoneum. Treatment is with corticosteroids.

The syndrome of retractile mesenteritis (sometimes referred to as sclerosing mesenteritis or mesenteric panniculitis) may present with abdominal discomfort, pain, diarrhoea and weight loss. Chronic fibrosing inflammation involves the root of the mesentery and small bowel. In some cases it has been associated with retroperitoneal fibrosis a desmoid or carcinoid tumour of the small bowel. It is more common in males and may have a prolonged debilitating course. Treatment is with tamoxifen and corticosteroids.

Leiomyomatosis peritonealis disseminata is an uncommon condition characterized by subperitoneal proliferation of benign nodules composed of smooth muscle cells. It is most common in premenopausal women and hormonal influences may play a role in its pathogenesis. The macroscopic appearance mimics peritoneal carcinomatosis but the clinical course is usually benign.

Endometriosis

Endometriosis is defined as the presence of endometrium and stroma outside the uterine cavity and myometrium was first described by von Rokitansky in 1860. It is commonly asymptomatic and occurs in up to 15% of menstruating women. Involvement of the bowel is much less common and only rarely causes symptoms, but when they occur they are often debilitating and may take years to be diagnosed. The pathogenesis is considered to be retrograde passage of endometrial tissue into the pelvic organs and subsequent spread by haematogenous or lymphatic dissemination. When implanted, the tissue continues to be hormonally modulated. It is most commonly left-sided within the abdomen in the rectosigmoid region (80%) followed by ileum, caecum, and appendix. Small serosal endometriotic nodules rarely cause symptoms, but large collections and those in a subserosal location may result in vague abdominal and back pain, diarrhoea, constipation, and abdominal bloating, symptoms that closely mimic the irritable bowel syndrome. Rectal bleeding may occur, but symptoms are not often cyclical. Symptomatic endometriosis is found in women of childbearing age and is uncommon before age of 20 years. It is important to consider the diagnosis in any women with prolonged symptoms suggestive of the irritable bowel syndrome who does not respond to initial therapies and in those whose pain is not relieved by defecation. Nevertheless, diagnosis may be difficult as symptoms can be multiple and diffuse especially if the lesions are widespread. Imaging is the mainstay of diagnosis and includes transvaginal ultrasonography, double contrast barium enemas, and colonoscopy, but endometriosis is increasingly being identified with MRI. The presence of methaemoglobin from recurrent haemorrhage within the lesion causes hyper-intense T1 weighted images and hypo-intensity on T2. Old endometriotic lesions with significant fibrosis are less well identified on MRI, and CT scans may be necessary. Some cases are only diagnosed at laparotomy or laparoscopic examination of the bowel. Management must be individualized and can include in some a solely expectant and conservative approach or medical therapy. Few trials have been performed. Inducing a pseudo-pregnancy state with low-dose oestrogen–progestogen is not recommended for intestinal disease, and agents that are effective in pelvic endometriosis including the synthetic androgen danazol or gonadotrophin-releasing hormone agonists may not be appropriate in bowel endometriosis as they may promote fibrosis. A cautious trial of therapy as a first line may be indicated but laparoscopy or surgery will be needed in those with severe symptoms or partial bowel obstruction.

Isolated ulcers of the intestine

Solitary rectal ulcer syndrome

The solitary rectal ulcer syndrome is somewhat misnamed as it may occasionally occur above the rectum and be multiple or circumferential. It occurs across the age spectrum and is seen into the ninth decade. The ulcer may be at one end of the spectrum of clinical disorders associated with rectal mucosal prolapse and caused in most cases by mucosal ischaemia and infarction. It presents with blood per rectum in 90% of cases and less frequently with abdominal pain, mucus per rectum, straining at defecation, diarrhoea, and constipation. The cases are commonly anaemic and the symptoms have serious impact on the quality of life. The ulcers may be located anteriorly (70%), posteriorly or circumferentially, and are multiple in one-third of cases. At colonoscopy the ulcer may be surrounded by a minimal area of inflamed mucosa or it may be at the end of a polypoid lesion simulating a carcinoma. Biopsy is crucial to rule out that diagnosis. Histology usually shows evidence of ischaemia but the characteristic feature is hypertrophy of the muscularis mucosae with smooth muscle fibres extending between the crypts and down into the epithelium. Treatment is commonly difficult but should be centred on correction of constipation with bulking agents (with or without lactulose) and patients should be warned not to strain at stool. Topical treatments with 5-aminosalicylic acid or corticosteroids have been helpful in small series. As these ulcers can remit spontaneously, it is difficult to be sure whether treatment has been effective in an individual patient. For patients with continuing disabling symptoms, anorectal physiological measurements should be considered because there may be evidence of impaired pelvic floor muscle innovation. A defecating proctogram may determine whether the anorectal angle changes when the patient attempts to empty the rectum and record the degree of mucosal prolapse. Surgical therapy with a rectopexy may be helpful in some cases.

Stercoral ulcers

These occur in association with faecal impaction and are most commonly found in the recto sigmoid area. The patients are usually elderly, but these ulcers can occur at any age in severely constipated individuals, including patients with a neurological cause for constipation. The common symptoms are those associated with constipation—nausea, abdominal distension, pain, and anorexia. The ulcers are frequently asymptomatic but may be the cause of anaemia from chronic bowel loss. The differential diagnosis includes other ulcers within the colon, particularly those with an infectious cause (tuberculosis and amoebiasis) as well as malignancy.

Isolated ulcers of the large intestine not associated with underlying colitis are rare but may be an incidental finding on screening colonoscopy or present with abdominal pain, acute blood per rectum bleeding, or chronic gastrointestinal blood loss. A common cause, particularly when the ulcers are caecal or right sided, is the use of nonsteroidal anti-inflammatory drugs.

Protein-losing enteropathy

This is a syndrome due to excessive loss of protein from the gastrointestinal tract. It should be considered in any case where hypoproteinaemia or a low albumin cannot be explained by renal loss (nephritic syndrome) or reduced hepatic synthesis. The cardinal features are peripheral oedema, occasionally diarrhoea and weight loss. There is a low albumin (occasional falling to very low levels, <15 g/dl), reduced immunoglobulins, caeruloplasmin, and fibrinogen.

Gastrointestinal protein loss may be due to a wide range of cause (Box 15.26.2). Increased interstitial pressure within the intestine can lead to protein loss due to lymphangiectasia (Waldmann’s disease, lymphedema–lymphangiectasia–mental retardation, Hennekam syndrome), chronic lymphatic obstruction due to tuberculosis, sarcoidosis, lymphoma, retroperitoneal fibrosis, or in association with an elevated right-sided heart pressure (constrictive pericarditis, following Fontan’s procedure). Various ulcerative disorders of the gastrointestinal tract include severe erosive gastritis, Crohns disease, pseudomembranous colitis, and acute graft vs host disease. Finally, it has been associated with Menetrier’s disease, bacterial overgrowth of the small bowel, Whipple’s disease, eosinophilic gastroenteritis, coeliac disease, and tropical sprue. A number of radio-isotopes have been used for diagnosis, with 51Cr-labelled chromium chloride being most commonly used. Stool α‎1-antitrypsin levels are also used, as this protein is not broken down within the gut. Treatment should be aimed at raising the serum albumin level and management for each specific cause of the protein loss.

Malakoplakia

This is a rare chronic granulomatous condition, most commonly affecting the genitourinary tract, skin, lung, bone, or brain; within the gastrointestinal tract it is most common in the sigmoid colon or rectum. It is observed in two clusters: in children and older people. It is more common in diabetic, immunosuppressed, or immunocompromised patients including those with hypogammaglobulinaemia, HIV infection, or after organ transplantation. Yellowish soft plaques 1 to 20 mm diameter show a histiocytic infiltrate with eosinophils and characteristic basophilic laminated calcium containing Michaelis–Guttman bodies. It may occur with isolated rectosigmoid involvement, as diffuse colonic involvement or as a focal lesion associated with a polyp or cancer. It is usually considered to be a granulomatous reaction to a chronic infection: Escherichia coli, klebsiella and proteus have been implicated. Treatment has revolved around antibiotic therapy (quinolone and co-trimoxazole–trimethoprim) and minimizing immunosuppression.

Intestinal pseudo-obstruction

Acute colonic pseudo-obstruction

Acute massive dilatation of the caecum and right colon, sometimes extending into the transverse and left side of the colon, can occur following intra-abdominal surgery for any cause as well as in any critically ill patient with severe sepsis, respiratory, or cardiac disease. In Ogilvie’s original report two patients had retroperitoneal malignancy, currently an exceptionally rare cause for this syndrome. Most patients have constant dull pain with marked abdominal distension associated with vomiting. There is constipation, but many patients continue to pass wind and some occasionally have diarrhoea despite the colonic dilatation. Bowel sounds are variable in pitch and frequency but are absent only rarely. The diagnosis is made on a plain radiograph of the abdomen which can be undertaken to monitor the risk of colonic perforation—the main risk from this disorder. The differential diagnosis includes toxic megacolon (a complication of inflammatory bowel disease or C. difficile infection) and mechanical colonic obstruction. Intravenous fluids and electrolytes are given, together with nasogastric suction, and any drugs that might be implicated in reduced colonic motility, e.g. opioids, tricyclic antidepressants, or anticholinergic agents, should be stopped. Pharmacological stimulation has been recommended with neostigmine (an acetylcholinesterase inhibitor), and small controlled trials have been positive. There are some reports of success with other prokinetic agents such as erythromycin or cisapride. Decompression of the colon with a rectal tube or with colonoscopy is occasionally needed although the long-term value has been contested. Equally it has previously been recommended that the patient is turned from side to side at regular intervals or nursed prone with elevated hips, although the benefit of this is not proven. Very rarely surgical decompression with a caecostomy may be needed if the colon is more than 12 cm diameter, which may be accompanied by resection if there is evidence of obvious colonic ischaemia.

Chronic intestinal pseudo-obstruction

This is a rare syndrome associated with symptoms and signs suggesting mechanical obstruction of the large or small bowel in the absence of any obstructive lesion. A similar disorder of the intestinal but without features of obstruction or bowel dilatation has been termed ‘chronic intestinal dysmotility’. The main features are of nausea, repeated vomiting, and abdominal pain. There may be significant bowel distension and constipation or occasionally diarrhoea. Bowel sounds are usually hyperactive. There are a number of causes (Box 15.26.3) which include familial visceral neuropathies and myopathies, which may present in infancy or adulthood; collagen vascular disorders; neuromuscular disorders and endocrinopathies; infections; and with some drugs. The diagnosis requires features of colonic or small-bowel dilatation and may require specific electrophysiological studies or full-thickness bowel biopsy at laparotomy. Treatment is directed at the underlying disease or the use of prokinetic agents. Rarely surgery may be needed for isolated sections of affected bowel or substantial sections if symptoms are severe and chronic. Some cases have done well following small-bowel transplantation.

Further reading

Cameron IC, et al. (1995). Intestinal endometriosis: Presentation, investigation, and surgical management. Int J Colorectal Dis, 10, 83–6.Find this resource:

Cipolletta L, et al. (1995). Malakoplakia of the colon. Gastrointest Endosc, 41, 225–8.Find this resource:

Gagliardi G, et al. (1996). Pneumatosis coli: A proposed pathogenesis based on study of 25 cases and review of the literature. Int J Colorectal Dis, 11, 111–18.Find this resource:

Giallourakis CC, Rosenberg PM, Friedman LS (2002). The liver in heart failure. Clin Liver Dis, 6, 947–67.Find this resource:

Kelly D (2006). Intestinal failure associated liver disease—what do we know today? Gastroenterology, 130, 870–7.Find this resource:

Nyhlin N, et al. (2006). Systematic review: microscopic colitis. Aliment Pharmacol Ther, 23, 1525–34.Find this resource:

Webster G, Buroughs A, Riordan S (2005). Portal vein thrombosis—new insights into aetiology and management. Aliment Pharmacol Ther, 21, 1–9.Find this resource: