Nonocclusive ischemic colitis following glycerin enema in a patient with coronary artery disease. A case report

Ischemic colitis after enema administration: Incidence, timing, and clinical features

BACKGROUND

Enema administration is a common procedure in the emergency department (ED). However, several published case reports on enema-related ischemic colitis (IC) have raised the concerns regarding the safety of enema agents. Nevertheless, information on its true incidence and characteristics are still lacking.

AIM

To investigate the incidence, timing, and risk factors of IC in patients receiving enema.

METHODS

We consecutively collected the data of all adult patients receiving various enema administrations in the ED from January 2010 to December 2018 and identified patients confirmed with IC following enema. Of 8320 patients receiving glycerin enema, 19 diagnosed of IC were compared with an age-matched control group without IC.

RESULTS

The incidence of IC was 0.23% among 8320 patients receiving glycerin enema; however, there was no occurrence of IC among those who used other enema agents. The mean age ± standard deviation (SD) of patients with glycerin enema-related IC was 70.2 ± 11.7. The mean time interval ± SD from glycerin enema administration to IC occurrence was 5.5 h ± 3.9 h (range 1-15 h). Of the 19 glycerin enema-related IC cases, 15 (79.0%) were diagnosed within 8 h. The independent risk factors for glycerin-related IC were the constipation score [Odds ratio (OR), 2.0; 95% confidence interval (CI): 1.1-3.5, P = 0.017] and leukocytosis (OR, 4.5; 95%CI: 1.4-14.7, P = 0.012).

CONCLUSION

The incidence of glycerin enema-related IC was 0.23% and occurred mostly in the elderly in the early period following enema administration. Glycerin enema-related IC was associated with the constipation score and leukocytosis.

Pharmacologically mediated colon ischemia

Colon ischemia (CI) is the most common form of ischemic injury of the gastrointestinal tract. Determining the precise incidence of CI is a challenging task, because of its often brief, mild nature, and frequent spontaneous resolution, as well as its misdiagnosis as other diseases. While many underlying disease conditions may predispose patients to CI, an important and possibly overlooked etiology is that of pharmacologically induced alterations of colonic blood flow. This review details the pharmacologic agents known to be associated with CI; when possible, their mechanisms of action are described. The aim of this paper is to highlight this often unrecognized cause of CI, thereby helping physicians to be aware of the association, to recognize its occurrence promptly, and to possibly reduce morbidity and mortality.

Kardiovaskuläre Begleiterkrankungen und Komplikationen bei Darmerkrankungen

Vascular diseases are not encountered very often in gastroenterology, though in cases of ischemic colitis a coronary heart disease is often present. In addition, heart diseases such as coronary heart disease, atrial fibrillation, and congestive heart failure are important risk factors for ischemic colitis and should be treated to avoid further ischemic episodes of the gut. The most common extraintestinal manifestations of Crohn's disease and ulcerative colitis are observed in the eye, on the skin, and in the liver region. Involvement of the cardiovascular system does not seem to be very common, though systematic epidemiological data on the significance of these extraintestinal complications--which certainly influence the prognosis--are lacking. Other patients with Crohn's disease or ulcerative colitis suffer from vasculitis, which reflects a further manifestation of inflammatory diseases affecting the cardiovascular system. Another important complication is activation of coagulationfactors, especially during active flare-up of intestinal disease; this can result in thromboembolic events. Systematic studies or investigations on the epidemiology of cardiovascular complications are still lacking, so that an overview of the published data is given. Metastatic tumors of the heart are rare, but there are case reports of cardiac metastases in patients with carcinomas of the colon. Carcinoid heart syndrome, another cardial complication of malignant disease, can prejudice the prognosis of patients with neuroendocrine tumors of the gastrointestinal tract.

Ischemic enterocolitis examined by colonoscopy and selective angiography

AIM: To study the value of colonoscopy and selective angiography in diagnosing ischemic enterocolitis.

METHODS: Among the 16 cases under study, 10 cases had hypertension and a history of coronary artery disease (one was hospitalized for sub-ventricular-wall infarction). The blood pressure of 10 of the 16 cases ranged from 13.9-23.8 to 13.3-14.6 kPa (170-180/100-110 mmHg). Two cases had chronic auricular fibrillation, and in four cases, a cardiogram showed left-front branch conduction block. Sixteen patients were examined by colonoscopy. Among them, 14 cases had a long course of angiocardiac disease, and were further examined by selective mesenteric inferior angiography.

RESULTS: The colonoscopy revealed local mucous hyperemia edema and blood on contact. Lesions were found in the sigmoid colon in four cases, in the descending colon in eight cases and in splenic flexure in four cases, which suggests that the lesion always appeared in the left part of colon. There were different degrees of inflammatory cell infiltration, submucous bleeding, edema, fibro-embolism and hemosiderosis by biopsy in the 16 patients whose membranes affect part of the enteral wall. Of the 14 patients examined by mesenteric inferior angiography, 3 cases showed mesenteric amphraxis inferior and formation of collateral circulation. There were different degrees of stenosis in the other 11 subjects’ mesenteric inferior cavities which grew slim and their branches were stenotic, so the radiographic image was not complete and the ends of some branches even cannot be seen.

CONCLUSION: The colonoscopy and the selective mesenteric inferior angiography are both helpful in the diagnosis of ischemic enterocolitis.

Colonic toxicity of administered drugs and chemicals

Although uncommon, medication-induced colonotoxicity is important to recognize because medication cessation generally leads to prompt clinical improvement, while medication continuation results in disease exacerbation. This review categorizes the association between medications and colonotoxicity as "well-established" or "probable," according to the following criteria: total number of reported cases, number of different research groups reporting an association, experimental and pharmacologic evidence of an association, and validity of an association in each reported case. Cocaine, ergotamine, estrogen, sodium polystyrene, alosetron, amphetamines, pseudoephedrine, and vasopressin are associated with colonic ischemia. The mechanisms include vasospasm, thrombogenesis, and shunting of blood from mesenteric vessels. Narcotics, phenothiazines, vincristine, atropine, nifedipine, and tricyclic antidepressants are associated with colonic pseudo-obstruction. The mechanisms include antagonizing prokinetic neurotransmitters, stimulating antikinetic neurotransmitters, promoting dysmotility, relaxing smooth muscle, and injuring enteric neurons. Numerous antibiotics are associated with pseudomembranous colitis; ampicillin is associated with hemorrhagic colitis; chemotherapy is associated with neutropenic colitis; and deferoxamine is associated with Yersinia enterocolitis. Mechanisms of these toxicities include altering normal bowel flora, weakening immunologic defenses, promoting microorganism virulence, and mucosal injury. Gold compounds, nonsteroidal antiinflammatory drugs, alpha-methyldopa, salicylates, and sulfasalazine are associated with an inflammatory or cytotoxic colitis. The mechanisms include direct mucosal cytotoxicity, antimetabolite effects, or drug allergy. Nonsteroidal antiinflammatory drugs, cyclo 3 fort, flutamide, lansoprazole, and ticlopidine are associated with lymphocytic colitis. The mechanisms include immunologic activation or attenuated immunologic defenses. Chronic cathartic use leads to colonic hypomotility and abdominal distention. Intrarectally administered corrosive compounds can produce a toxic colitis.

CT of acute bowel ischemia

Bowel ischemia may be caused by many conditions and manifest with typical or atypical and specific or nonspecific clinical, laboratory, and radiologic findings. It may mimic various intestinal diseases and be confused with certain nonischemic conditions clinically and at computed tomography (CT). Bowel ischemia severity ranges from mild (generally transient superficial changes of intestinal mucosa) to more dangerous and potentially life-threatening transmural bowel wall necrosis. Causes of critically reduced blood flow to the bowel are diverse, ranging from occlusions of mesenteric arteries or veins to complicated bowel obstruction and overdistention. CT can demonstrate changes in ischemic bowel segments accurately, is often helpful in determining the primary cause of ischemia, and can demonstrate important coexistent findings or complications. Unfortunately, common CT findings in bowel ischemia are not specific, and specific findings are rather uncommon. Therefore, it often is a combination of nonspecific clinical, laboratory, and radiologic findings-especially detailed knowledge about the pathogenesis of acute bowel ischemia in different conditions-that helps most in correct interpretation of CT findings. To improve understanding of this complex heterogeneous entity, this article provides an overview of the anatomy and physiology of mesenteric perfusion and discussions of causes and pathogenesis of acute bowel ischemia, CT findings in various types of acute bowel ischemia, and potential pitfalls of CT.

Unusual causes of mesenteric ischemia

Although complications of generalized atherosclerosis most commonly cause intestinal ischemia, a number of unusual causes may be responsible. These unusual causes can be grouped into six major categories: (1) mechanical, (2) drugs, (3) hematologic, (4) endocrine, (5) vasculopathies, and (6) miscellaneous. Morbidity and mortality rates remain high because these rare diseases frequently go unrecognized until patients suffer adverse outcomes. A high index of suspicion may decrease the delay in diagnosis of mesenteric ischemia caused by these disorders.