Nonocclusive Ischemic Colitis Research Articles

Increased Risk of Non-Occlusive Ischemic Colitis With Statin Use: A Case Control Study

Increased Risk of Non-Occlusive Ischemic Colitis With Statin Use: A Case Control Study

Idiopathic Myointimal Hyperplasia of Mesenteric Veins: An Uncommon Cause of Ischemic Colitis With Distinct Mucosal Features.

Idiopathic myointimal hyperplasia of mesenteric veins causes chronic ischemic mucosal injury with segmental strictures that mimic inflammatory bowel disease and nonocclusive ischemic colitis. It is characterized by myointimal proliferative changes that narrow the lumina of veins combined with ischemic injury and ulcers. Most cases reported to date have been diagnosed following surgical resection. The aim of this study was to determine whether mucosal changes of idiopathic myointimal hyperplasia of mesenteric veins are sufficiently sensitive and specific to allow its recognition in biopsy material. The study group consisted of 10 patients with idiopathic myointimal hyperplasia of mesenteric veins who underwent surgical resection of the affected colon, 7 of whom had available prior endoscopic biopsies. The control group included 10 patients each with radiation, nonocclusive ischemia, Crohn disease, diverticulitis, and mucosal amyloidosis, and 5 cases of small vessel (leukocytoclastic) vasculitis. Study patients were mostly older men with distal colorectal disease. All resection specimens showed mucosal ischemia with numerous thick-walled (arteriolized) capillaries and glassy subendothelial fibrin deposits; numerous hyalinized, eosinophilic thrombi were detected in 90% of colectomy specimens. Biopsies showed arteriolized capillaries (100%), subendothelial fibrin deposits (86%), fibrin thrombi (43%), and perivascular hyalinization (43%). Fibrin thrombi were observed in only one case each of ischemic colitis and small vessel vasculitis, and none of the other abovementioned features were seen in any of the controls. We conclude that arteriolized capillaries, subendothelial fibrin deposits, and perivascular hyalinization are frequent and specific features that can facilitate recognition of idiopathic myointimal hyperplasia of mesenteric veins in biopsy samples.

Poor prognostic factors in patients who underwent surgery for acute non-occlusive ischemic colitis.

IntroductionIschemic colitis (IC) is a disease with high postoperative morbidity and mortality. Knowledge of the risk factors for postoperative mortality could be helpful in clinical decision making and in optimizing postoperative treatment.MethodsFrom a prospective database, we conducted a retrospective medical record review of 50 patients who underwent surgery for IC between 2003 and 2011 at our institution. We analyzed the causes and potential risk factors for early mortality after surgery for IC.ResultsThe early postoperative mortality and morbidity rates were 30.0% (15/50) and 54% (27/50), respectively. The two most common causes of death were multi-organ failure (66.7%, 10/15) and fulminant septic shock (20.0%, 3/15). Univariate analysis showed that postoperative mortality was significantly associated with preoperative nephropathy, coronary artery disease, a previous history of cardiovascular surgery, an ASA score ≥ 4, surgical delay ≥ 3 days, preoperative hemodynamic instability, and use of pre- and intraoperative adrenergic vasopressors. In the multivariate analysis, a previous history of cardiovascular surgery (odds ratio [OR], 8.2; 95% confidence interval [CI], 1.2–56.5) and surgical delay ≥ 3 days (OR, 5.7; 95% CI, 1.2–27.9) were identified as independent risk factors for postoperative mortality.ConclusionsBecause surgical delay is an avoidable determinant of early mortality, a high index of suspicion and early surgical intervention can increase survival. A routine postoperative evaluation for IC may be helpful in patients with a previous history of cardiovascular surgery.

Restoration of intestinal continuity after colectomy for non-occlusive ischemic colitis

Non-occlusive ischemic colitis (IC) is a rare and life-threatening abdominal disease associated with high rates of postoperative mortality. When surgery is performed, in patients with IC, either a Hartmann's procedure (HP) or a total colectomy and ileostomy is required. The possibility of restoration of intestinal continuity in surviving patients is an important issue. The aim of the present study was to report the outcome of surgically managed IC patients and to identify predictive factors for restoration of intestinal continuity and to assess the results of this procedure. Between January 1997 and May 2011, 96 IC patients underwent total colectomy and 68 underwent left colectomy. IC was spontaneous in 62 patients and occurred after prior surgery in 102. Eighty patients died during the postoperative period and nine died during the follow-up from an unrelated disease. Fifteen patients were lost to follow-up. The remaining 60 surviving patients were our study population. There were 44 men and 16 women with a mean age of 67 years ± 12 SD. Restoration of bowel continuity was performed in 24 patients (40%). There were no predictive factors for restoration of intestinal continuity in terms of sex, age, IC etiology, and the extent of colon resection at primary surgery. The median interval between first surgery and restoration of bowel continuity was 7.9 months (range 0.2-35 months). There were no postoperative deaths and the overall morbidity rate was 45% (11/24). No patients developed anastomotic leak or underwent unplanned reoperation. Reversal of HP after IC is feasible in 40% of surviving patients with acceptable mortality and morbidity rates. This restoration of intestinal continuity should therefore be discussed for every surviving IC patient.

CT findings in acute, subacute, and chronic ischemic colitis: suggestions for diagnosis.

Purpose. This paper aims at evaluating CT findings of occlusive and nonocclusive ischemic colitis (IC), in correlation with the etiology and the different phases of the disease. Materials and Methods. CT examination and clinical history of 32 patients with proven IC were retrospectively reviewed. The CT findings were analyzed according to the different phases of the disease (acute, subacute, and chronic). Results. Among the 32 CT examinations performed in the acute phase, 62.5% did not present signs of occlusion of the superior mesenteric artery (SMA) or inferior mesenteric artery (IMA), whereas IMA occlusion was detected in 37.5% of CT examinations. In the acute phase, the presence of pericolic fluid was found in 100% of patients undergoing progressive resorption from acute to subacute phase if an effective reperfusion occurred; the bowel wall thickening was observed in 28.1% patients in acute phase and in 86.4% patients evaluated in subacute phase. The unthickened colonic wall was found in all conditions where ischemia was not followed by effective reperfusion (71.9% of cases), and it was never found in chronic phase, when the colon appeared irregularly thickened. Conclusion. CT allows determining the morphofunctional alterations associated with the IC discriminating the occlusive forms from the nonocclusive forms. CT, furthermore, allows estimating the timing of ischemic damage.

Ischemic colitis: Who will survive?

Operative treatment for acute ischemic colitis is associated with a high morbidity and mortality. These patients often have a prolonged postoperative stay in the intensive care unit with an uncertain outcome. In this study, we aimed to develop a predictive risk score for perioperative mortality and to examine long-term follow-up of patients with acute ischemic colitis. All patients (n = 177) undergoing surgical treatment for acute ischemic colitis in our institution from 2002 to 2008 were prospectively included in this study. Independent predictors of perioperative mortality and poor long-term survival were assessed by uni- and multivariate analysis. A risk score including various perioperative variables (nonocclusive ischemic colitis, acute renal failure, extent of bowel ischemia, serum lactate, and duration of catecholamine therapy) was defined being highly predictive for postoperative mortality of patients having undergone an operation for acute ischemic colitis. Mesenteric atherosclerosis in the surgical specimen is an independent prognostic factor for poor long-term survival (52 vs 40 months with mesenteric atherosclerosis; P = .027). This study for the first time presents a risk score highly predictive of postoperative mortality of patients undergoing an operation for ischemic colitis. Our score may help to further select and modify therapeutic management in patients with acute ischemic colitis on the basis of validated data. Furthermore, we could demonstrate a significant influence of mesenteric atherosclerosis on long-term survival of patients with acute ischemic colitis.

Isolated cecal necrosis mimicking acute appendicitis: a case series

IntroductionSpontaneous non-occlusive ischemic colitis involving the cecum alone (isolated cecal necrosis) is a rare condition that is generally due to a low-flow state: shock. It presents with right lower quadrant abdominal pain and may resemble acute appendicitis. Little is known about postoperative ischemic necrosis of the remaining colon after surgical treatment of isolated cecal necrosis. We report four cases of isolated cecal necrosis mimicking acute appendicitis seen at our institution within a 4-year period.Case presentationThe patients were two men and two women with a mean age at diagnosis of 59 years (range 46-68). The patients were of Turkish ethnic origin. All patients presented to the emergency room with acute abdominal pain and had symptoms of nausea and vomiting. The medical histories for three of the patients revealed end-stage renal failure requiring hemodialysis. The other patient had chronic obstructive pulmonary disease. Right hemicolectomy with anastomosis was performed in three patients and cecal resection with ileocolostomy was performed in the remaining one patient. All of the patients healed without complications. Median follow-up of patients was 24.5 (range: 17-37) months. There was no recurrence of ischemia in the remaining colon during the follow-up period of the patients.ConclusionIsolated cecal infarction should be included in the differential diagnosis of acute pain in the right lower quadrant of the abdomen, especially in those patients on chronic hemodialysis. While diffuse ischemic disease of the intestine has high morbidity, mortality and recurrence rates, patients with isolated cecal necrosis have a good prognosis with early diagnosis and surgical treatment compared to those with diffuse ischemic disease.

Aggressive Management of Nonocclusive Ischemic Colitis Following Aortic Reconstruction

Aggressive Management of Nonocclusive Ischemic Colitis Following Aortic Reconstruction

Aggressive Management of Nonocclusive Ischemic Colitis Following Aortic Reconstruction

Under standard conditions following aortic reconstruction, nonocclusive ischemic colitis (IC) type 1 (mucosal ischemia) and type 2 (mucosal and muscularis ischemia) can be managed nonoperatively, whereas type 3 (transmural ischemia) requires emergency surgery. Our objective was to standardize the surgical approach for IC complicating aortic reconstruction. Retrospective cohort study. General surgery, vascular surgery, anesthesiology, and critical care units in a university-affiliated hospital. From January 5, 1997, to December 15, 2003, 49 cases of IC complicating aortic reconstruction were diagnosed (rate, 2.7%). Nonoperative management was used for patients with type 1 or type 2 without multiple organ failure (MOF). All patients with type 3 or with type 2 with MOF underwent urgent resection of the ischemic colon without anastomosis. Immediate surgery was performed on 24 patients (49.0%). Nineteen (76.0%) of 25 patients without MOF and with transient endoscopic findings underwent secondary surgery for progression to final IC type 3 (16 patients) or to final IC type 2 with MOF (3 patients). Twenty-three (53.5%) of 43 patients died after colorectal resection (overall mortality, 46.9%). Factors causing significant risk of death were surgery, MOF, final IC type, and amount of perioperative transfusion. The mortality was 57.1% for final IC type 3, 37.5% for final IC type 2 with MOF, and 0% for final IC type 1 or type 2 without MOF. Selective management of postoperative IC, based on MOF and the degree of ischemia, is the suggested course of action. For patients with mild ischemia and MOF, an aggressive approach is recommended.

Shock‐Associated Nonocclusive Ischemic Colitis in an Infant: A Very Rare Complication of Incarcerated Inguinal Hernia

Shock‐Associated Nonocclusive Ischemic Colitis in an Infant: A Very Rare Complication of Incarcerated Inguinal Hernia

Pathogenesis of nonocclusive ischemic colitis.

The nonocclusive component of ischemic colitis in anesthetized pigs was mimicked using cardiogenic shock produced by pericardial tamponade. Increases in pericardial pressure produced decreases in arterial pressure (PA) and cardiac output (CO), with corresponding rises in total peripheral resistance (i.e., cardiogenic shock). This was associated with marked reductions in blood flow through the inferior mesenteric artery (IMA), due primarily to disproportionate increases in IMA vascular resistance. Levels of plasma renin activity correlated closely with these changes in mesenteric hemodynamics. Confirmed, total alpha adrenergic blockade with phenoxybenzamine failed to block this selective mesenteric vasoconstriction, while ablation of the renin-angiotensin axis with captopril completely abolished it, thereby ameliorating the colonic ischemia. Central intravenous infusions of pathophysiologic levels of angiotensin II, without tamponade, mimicked the response to shock seen with tamponade alone. In an additional group of pigs, 4 hours of sustained shock (tamponade) followed by 2 hours of normotension (release of tamponade and resuscitation) produced lesions characteristic of ischemic colitis, including full-thickness mucosal ulceration. Such lesions were ameliorated significantly in pigs in which the renin-angiotensin system had been ablated by bilateral nephrectomy. Nonocclusive ischemic colitis appears to be mediated primarily by a remarkable sensitivity of the colonic vasculature to the renin-angiotensin axis.

Inferior Mesenteric Arteriovenous Fistula Associated With Portal Hypertension and Acute Ischemic Colitis

Abstract The authors report a case of postoperative arteriovenous fistula between the inferior mesenteric vessels. This fistula was revealed by portal hypertension, with bleeding esophageal varices, ascites, and encephalopathy, and by acute ischemic colitis. Histologic examination of the liver was normal. All of the symptoms disappeared after transcatheter embolization of the fistula with stainless steel coils. This case report favors the reality of the so-called forward portal hypertension and suggests that inferior mesenteric arteriovenous fistula might be a factor predisposing to nonocclusive ischemic colitis.

Inferior mesenteric arteriovenous fistula associated with portal hypertension and acute ischemic colitis: Successful occlusion by intraarterial embolization with steel coils

The authors report a case of postoperative arteriovenous fistula between the inferior mesenteric vessels. This fistula was revealed by portal hypertension, with bleeding esophageal varices, ascites, and encephalopathy, and by acute ischemic colitis. Histologic examination of the liver was normal. All of the symptoms disappeared after transcatheter embolization of the fistula with stainless steel coils. This case report favors the reality of the so-called “forward” portal hypertension and suggests that inferior mesenteric arteriovenous fistula might be a factor predisposing to nonocclusive ischemic colitis.

Non-occlusive ischemic colitis: angiographic aspects in a canine model.

A model of non-occlusive colonic ischemia (NCI) was produced in the dog, incorporating both moderately decreases systemic pressure and increased intralumenal colonic pressure. These factors may play an etiologic role in human NCL. When differences between mean systemic and mean distention pressures were 30 mmHg or less, severe mucosal injury occured. In no case was the muscularis injured. Moderate systemic hypotension alone, or moderate colonic distention alone, did not produce significant colonic ischemic injury. Colonic distention with pressures of 60 mmHg alone resulted in colonic mucosal necrosis, but these pressures are beyond those ordinarily encountered clinically, even in large bowel obstruction. Angiography may be useful in demonstrating reduced flow to the colon during development of colonic ischemic injury. However, angiography is not a sensitive method in the diagnosis of nonocclusive colonic ischemic injury, once that injury has been established and inciting factors have subsided.