Ischemic colitis: patterns and prognosis

Can Thrombosed Abdominal Aortic Dissecting Aneurysm Cause Mesenteric Artery Thrombosis and Ischemic Colitis?-A Case Report and a Review of Literature

Background/Objectives: Ischemic colitis, typically caused by thrombosis or reduced blood flow in the inferior mesenteric artery, is the most common ischemic lesion at the colorectal level. This case contributes to existing knowledge by highlighting the rare co-occurrence of a thrombosed aortic aneurysm and ischemic colitis, pointing to a direct vascular etiology rather than a multifactorial or idiopathic cause. Methods: A thorough electronic search was conducted on PubMed to identify risk factors and etiological determinants of ischemic colitis. Results: We present the case of a 70-year-old male with diffuse abdominal pain and multiple cardiac comorbidities. A CT scan revealed aeroenteritis, aerocolia, fusiform aneurysmal dilation of the abdominal aorta (18 cm long, 7.3 cm in diameter, from below the renal arteries to the bifurcation), parietal thrombosis, a circulating lumen of 2.7 cm, and inferior mesenteric artery thrombosis. Intraoperatively, necrosis was found in the upper rectum, sigmoid colon, descending colon, and the middle third of the left transverse colon, with clear demarcation between healthy and necrotic tissue. A subtotal proctocolectomy with transverse colostomy was performed. Conclusions: This case highlights ischemic colitis as a vascular disorder, urging broader differential diagnosis when common causes are unclear. Timely imaging, a multidisciplinary approach, and attention to vascular risks are key to identifying rare causes like aneurysmal thrombosis. While thrombosed abdominal aortic aneurysms can cause mesenteric ischemia, their link to ischemic and ulcerative colitis is unique, emphasizing the importance of accurate risk assessment in treatment planning.

Prior appendectomy and cerebral infarction as potential risk factors for recurrent ischemic colitis: A retrospective observational study

Background and Aim

Ischemic colitis (IC) is a benign disease associated with acute lower gastrointestinal bleeding and frequent recurrence. While several studies have investigated risk factors for IC onset, few have assessed the risk factors for recurrent IC. This study aimed to identify risk factors for recurrent IC.

Methods

Potential risk factors for recurrence were assessed by examining medical records and laboratory findings in this single-center retrospective study. We extracted the following data from the patients' medical records: patient characteristics, clinical signs and symptoms, laboratory findings, method of treatment, length of hospital stay, disease course, and the frequency of IC morbidities. Patients with IC were selected from a total of 439 312 patients over an 11-year period. Patients were divided into recurrent and nonrecurrent IC groups.

Results

In total, 225 patients met the diagnostic criteria for IC during the specified study period; of these, 204 patients (90.7%) and 21 patients (9.3%) were included in the nonrecurrent and recurrent IC groups, respectively. Univariate and multivariate analyses showed a significant association between IC recurrence and both cerebral infarction (P = 0.008, odds ratio [OR] = 6.3) and history of appendectomy (P = 0.0005, OR = 6.2). The median (interquartile range [IQR]) follow-up time for all patients was 1556 (353-2768) days; this was much longer than the median (IQR) time to recurrence of 291 (64-907) days in the recurrent IC group.

Conclusion

The results of this study suggest that prior cerebral infarction and appendicectomy may be risk factors for IC recurrence.

Development and Validation of a Risk Scoring Model for Early Prediction of Severe Colon Ischemia

BACKGROUND

Colon ischemia (CI) is injury to the intestines secondary to insufficient blood flow. Its clinical severity can range from mild to life-threatening.

AIMS

To investigate predictive risk factors for CI and propose a scoring model for severe outcomes.

METHODS

We retrospectively analyzed the medical records of patients admitted to Chungnam National University Hospital from January 2010 to December 2018. CI was defined as severe when patients required surgery immediately or after initial conservative management, death occurred after hospitalization, or symptoms persisted after 2 weeks. By controlling for possible confounders from the logistic regression analysis, we obtained a new risk scoring model for the early prediction of severe CI. Furthermore, using the area under the receiver operating characteristics curve (AUROC), we assessed the accuracy of the model.

RESULTS

A total of 274 patients endoscopically diagnosed with CI were included, of whom 181 had severe CI. In the multivariate analysis, tachycardia, elevated C-reactive protein, Favier endoscopic classification stage ≥ 2, and history of hypertension were independently and significantly associated with severe CI. The AUROC of the model was 0.749.

CONCLUSIONS

This risk scoring model based on the presence of tachycardia, elevated C-reactive protein level, unfavorable endoscopic findings by Favier's classification, and the history of hypertension could be used to predict severe CI outcomes at an early stage.

Many faces of acute bowel ischemia: overview of radiologic staging

Acute bowel ischemia (ABI) can be life threatening with high mortality rate. In spite of the advances made in diagnosis and treatment of ABI, no significant change has occurred in the mortality over the past decade. ABI is potentially reversible with prompt diagnosis. The radiologist plays a central role in the initial diagnosis and preventing progression to irreversible intestinal ischemic injury or bowel necrosis. The most single imaging findings described in the literature are either non-specific or only present in the late stages of ABI, urging the use of a constellation of features to reach a more confident diagnosis. While ABI has been traditionally categorized based on the etiology with a wide spectrum of imaging findings overlapped with each other, the final decision for patient's management is usually made on the stage of the ABI with respect to the underlying pathophysiology. In this review, we first discuss the pathologic stages of ischemia and then summarize the various imaging signs and causes of ABI. We also emphasize on the correlation of imaging findings and pathological staging of the disease. Finally, a management approach is proposed using combined clinical and radiological findings to determine whether the patient may benefit from surgery or not.

Nationwide Study to Predict Colonic Ischemia after Abdominal Aortic Aneurysm Repair in The Netherlands

BACKGROUND

Colonic ischemia remains a severe complication after abdominal aortic aneurysm (AAA) repair and is associated with a high mortality. With open repair being one of the main risk factors of colonic ischemia, deciding between endovascular or open aneurysm repair should be based on tailor-made medicine. This study aims to identify high-risk patients of colonic ischemia, a risk that can be taken into account while deciding on AAA treatment strategy.

METHODS

A nationwide population-based cohort study of 9,433 patients who underwent an AAA operation between 2014 and 2016 was conducted. Potential risk factors were determined by reviewing prior studies and univariate analysis. With logistic regression analysis, independent predictors of intestinal ischemia were established. These variables were used to form a prediction model.

RESULTS

Intestinal ischemia occurred in 267 patients (2.8%). Occurrence of intestinal ischemia was seen significantly more in open repair versus endovascular aneurysm repair (7.6% vs. 0.9%; P < 0.001). This difference remained significant after stratification by urgency of the procedure, in both intact open (4.2% vs. 0.4%; P < 0.001) and ruptured open repair (15.0% vs. 6.2%); P < 0.001). Rupture of the AAA was the most important predictor of developing intestinal ischemia (odds ratio [OR], 5.9, 95% confidence interval [CI] 4.4-8.0), followed by having a suprarenal AAA (OR 3.4; CI 1.1-10.6). Associated procedural factors were open repair (OR 2.8; 95% CI 1.9-4.2), blood loss >1L (OR 3.6; 95% CI 1.7-7.5), and prolonged operating time (OR 2.0; 95% CI 1.4-2.8). Patient characteristics included having peripheral arterial disease (OR 2.4; 95% CI 1.3-4.4), female gender (OR 1.7; 95% CI 1.2-2.4), renal insufficiency (OR 1.7; 1.3-2.2), and pulmonary history (OR 1.6; 95% CI 1.2-2.2). Age <68 years proved to be a protective factor (OR 0.5; 95% CI 0.4-0.8). Associated mortality was higher in patients with intestinal ischemia versus patients without (50.6% vs. 5.1%, P < 0.001). Each predictor was given a score between 1 and 4. Patients with a score of ≥10 proved to be at high risk. A prediction model with an excellent AUC = 0.873 (95% CI 0.855-0.892) could be formed.

CONCLUSIONS

One of the main risk factors is open repair. Several other risk factors can contribute to developing colonic ischemia after AAA repair. The proposed prediction model can be used to identify patients at high risk for developing colonic ischemia. With the current trend in AAA repair leaning toward open repair for better long-term results, our prediction model allows a better informed decision can be made in AAA treatment strategy.

The sigmoidea ima artery: A player in colonic ischemia?

INTRODUCTION

The sigmoidea ima artery is defined as the lowest sigmoid artery, which forms the distal end of the marginal artery by linking with the superior rectal artery. It supplies the rectosigmoid junction, which is a critical area for ischemia. The aim of the present study was to delineate the area supplied by the inferior mesenteric artery with special consideration of the sigmoidea ima artery.

MATERIALS AND METHODS

The inferior mesenteric artery was dissected from its origin to the bifurcation of the superior rectal artery in 30 cadavers (15 male, 15 female). Vessel length and distance to the promontory were measured for each branch.

RESULTS

There were two manifestations of the sigmoidea ima artery, irrespective of the branching pattern of the inferior mesenteric artery. It originated below the promontory in 25 cases (83.3%) and above it in three (10%). It did not derive from the superior rectal artery in two cases (6.7%). In these 16.7%, the marginal artery was absent near the rectosigmoid junction.

CONCLUSIONS

We suggest the terms "arteria sigmoidea ima pelvina" and "arteria sigmoidea ima abdominalis" for the two variants. The terms "arteria marginalis pelvina" and "arteria marginalis abdominalis" could be applied in clinical practice. An abdominal marginal artery could be considered a risk factor for colonic ischemia in colorectal resections and abdominal aortic aneurysm repair. Both variants should be considered when pre- and intra-operative perfusion measurements are interpreted.

Nonocclusive Ischemic Colitis: Analysis of Risk Factors for Severity

The purpose of this study was to identify risk factors predictive of severe nonocclussive ischemic colitis (IC) requiring operation or resulting in mortality. One hundred seventeen patients with nonocclussive IC were identified and divided into two groups: those with severe disease (n = 24) and those with disease that resolved with supportive care (n = 93). Univariate and multivariate logistic regression models were used. The splenic flexure was the most common involved segment (57.3%), whereas the right colon was involved in 17.9 per cent of patients. Multivariate logistic regression identified three independent risk factors for severe disease: leukocytosis greater than 15 3 109/L (odds ratio [OR], 5.7; confidence interval [CI], 1.5 to 21), hematocrit less than 35 per cent (OR, 4.5; CI, 1.1 to 17), and history of atrial fibrillation (OR, 15; CI, 1.3 to 190). Right-sided IC and chronic renal insufficiency did not affect severity. Special attention should be given to patients with the following risk factors for a severe course: atrial fibrillation, elevated white blood cell count, and anemia. These factors might enable earlier identification of patients who may benefit from early operation. Further prospective studies focusing on subgroups of IC (occlusive and nonocclusive) are required.

Young-Onset Ischemic Colitis: A Condition of Elusive Etiology Frequently Associated With Immune Dysregulation

Ischemic colitis (IC) associates with older age, hypertension, and heart disease, among others. Young-onset IC is rare. We aimed to delineate clinical characteristics of young patients (<40 years) with IC. Cases from 1984 to 2017 were re-reviewed. Of the 60 cases available, 52% (n = 31) had histologic features of IC. Fifty-five percent were female with a mean age of 32 (range = 14-40) years. Fifty-eight percent (n = 18) were resections. The most common presentations were diarrhea and abdominal pain. Three teenagers had IC associated with prior surgery, volvulus, and constipation. In the 21- to 40-year group, 43% (n = 12) lacked clinical associations. A second subset (n = 6, 21%) had histories of immune dysregulation (lupus, dermatomyositis, vasculitis) and poorly controlled HIV/AIDS (n = 5, 18%). Smoking and cocaine were endorsed by 1 and 2 patients, respectively. One patient had premature atherosclerosis while another had HMG Co-A lyase deficiency. Vasculitis was identified in 22% of the resections and in none of the biopsies. Nineteen percent of patients died (n = 6) from complications of IC, all treated surgically, including 1 patient previously misdiagnosed as ulcerative colitis; 2 patients died of unrelated causes. While rare before 20 years of age, IC in teenagers relates to mechanical issues and is rare in children. Associations in young adults include immune dysregulation, cocaine and cigarette use, and premature atherosclerosis. Our retrospective cohort had a surgical mortality rate within the range reported by others, highlighting the importance of accurate diagnosis in young individuals.

Acute mesenteric ischaemia: a pictorial review

Abstract

Acute mesenteric ischaemia (AMI) is an uncommon cause of acute hospital admission with high mortality rates (50–90%) that requires early diagnosis and treatment. With the increase in average life expectancy, AMI represents one of the most threatening abdominal conditions in elderly patients. Untreated, AMI will cause mesenteric infarction, intestinal necrosis, an overwhelming inflammatory response and death. Early intervention can reverse this process leading to a full recovery, but the diagnosis of AMI is difficult. The failure to recognise AMI before intestinal necrosis has developed is responsible for the high mortality of the disease. Unfortunately, common CT findings in bowel ischaemia are not specific. Therefore, it is often a combination of nonspecific clinical, laboratory and radiological findings that helps most in the correct interpretation of CT findings. The purpose of this article is to provide an overview of the anatomy, physiology of mesenteric perfusion and discussions of causes, pathogenesis and CT findings in various types of acute bowel ischaemia. Familiarity with various imaging features of mesenteric injury is essential to make a timely diagnosis that will lead to improved patient outcomes.

Teaching Points

• AMI is a potentially life-threatening disorder whose prognosis depends on early recognition, accurate diagnosis and timely intervention.

• Arterial inflow occlusion due to thrombosis or embolisation is the most common cause of AMI.

• Four aetiological types of AMI have been associated with different characteristics and risk factors (EAMI, TAMI, VAMI and NOMI).

• Physical examination and laboratory findings are not sensitive or specific for diagnosing AMI; therefore, MDCT is still the first-line imaging method in suspected AMI.

• Although a number of scoring systems for prognosis have been proposed, these have not been validated in large-scale studies.

Predictors of severity in ischemic colitis: Usefulness of early ultrasonography

PURPOSE

The main objective was to evaluate the usefulness of early ultrasonography for determining prognosis of patients with ischemic colitis.

MATERIALS AND METHODS

We reviewed the histories of patients with diagnosis of ischemic colitis over a period of 11 years. Two hundred twenty nine patients with ischemic colitis were included. Demographic, clinical, laboratory and sonographic findings were retrospectively analyzed. Patients were divided into two groups according to the outcome: mild (those who improved with conservative treatment) or severe (those who died or required surgery), and the findings of each group were compared. In addition, we developed a predictive model of multivariate logistic regression analysis, and then it was validated in a different population of 58 consecutive patients with ischemic colitis.

RESULTS

The mild ischemic colitis group consisted of 184 patients (age 74,7±8,8years), and the severe group of 45 patients (age 78,6±7,7years). More pancolitis (p=0.005), altered pericolic fat (p=0.032) and free fluid (p=0.013) was observed in the severe ischemic colitis group compared with the mild group. Severe ischemic group had lower wall thickness (p=0.020) and higher resistive index than mild group (p=0.025). Multivariate analysis identified as protective factors to severe ischemic colitis: pain (p=0.026), diarrhea (p=0.034), rectal bleeding (p=0.000), and hypertension (p=0.001). Altered pericolic fat (p=0.008) and pancolitis (p=0.017) were sonographic findings significantly related to severe ischemic colitis. Our model correctly classified 88.4% of the study patients and 89.6% of the population of 58 patients used in validation.

CONCLUSIONS

Sonographic features with clinical findings can predict the outcome of ischemic colitis. Our predictive model could differentiate properly between patients with mild or severe ischemic colitis.

Advents in the Diagnosis and Management of Ischemic Colitis

BACKGROUND

Ischemic colitis (IC) is a common type of ischemic insult, resulting from decreased arterial blood flow to the colon. This disease can be caused from either atherosclerotic occlusive vascular disease or non-occlusive disease. The aim of this study is to present the diagnostic methodology and management of this severe disease based on current literature.

METHODS

A literature search has been done including articles referring to modern diagnosis and management of IC.

RESULTS

IC is usually a transient disease, but it can also cause gangrene of the colon, requiring emergency surgical exploration. Diagnosis is troublesome and is based on imaging examinations, mainly computerized tomography, which in association with colonoscopy can delineate the distribution pattern and severity of disease.

CONCLUSION

The majority of patients with mild disease have usually complete clinical recovery within a short period. The severe forms of the disease carry high morbidity and mortality rates and prompt surgical intervention is the only way to improve the associated severe prognosis.

Association between lower air pressure and the onset of ischemic colitis: a case-control study

OBJECTIVE

Ischemic colitis (IC) often affects the elderly. Proarteriosclerotic factors, such as hypertension and smoking, and cardiovascular disease are considered major contributors to IC. Although a possible link between certain cerebrocardiovascular disorders and meteorological phenomena has been reported, the relationship between IC onset and weather changes remains uninvestigated. This study examined whether specific meteorological factors were associated with the occurrence of IC.

PATIENTS AND METHODS

We retrospectively enrolled 303 patients who had been diagnosed with IC between January 2003 and June 2010 at Suwa Red Cross Hospital in Nagano Prefecture, Japan. The meteorological data of the days on which IC patients visited the hospital (IC+ days) were compared with those of the days on which IC patients did not (IC- days).

RESULTS

Univariate analysis indicated that IC+ days had significantly lower air pressure (P<0.001), depressed air pressure from the previous day (P<0.001), and fewer daylight hours (P<0.001), as well as higher air temperature (P=0.017), air humidity (P=0.004), wind velocity (P<0.001), and rainfall (P=0.012) compared with IC- days. Multivariate logistic regression analysis of the meteorological data showed that air pressure (odds ratio: 0.935, P<0.001) and change in air pressure from the previous day (odds ratio: 0.934, P<0.001) were related to onset of IC.

CONCLUSION

Lower air pressure and decrease in air pressure from the previous day are possible novel factors associated with the development of IC.

A Rare Case of Vasculitis Patched Necrosis of Cecum due to Behçet's Disease

Isolated cecal necrosis is a rare form of acute ischemic colitis and a rare cause of surgical abdomen. Behçet's disease is a multisystemic autoimmune condition which can induce vasculitis. This can result in cecal necrosis while disease involves colon vessels. We describe a patient with complicated Behçet's disease and ischemic colitis admitted to our hospital. Patient was a 62-year-old female with more accompanying diseases. Histopathologic findings confirmed the diagnosis of ischemic colitis and regarding patient's vision problem and skin lesions, rheumatologic tests were performed which were positive for HLAB5 and HLAB51 suggestive of Behçet's disease; the patient was improved with surgery. Abdominal pain can indicate a disease with vascular involvement like Behçet's disease, especially in the presence of other clinical findings suggestive of the disease including blurred vision and skin lesions. An abdominal computerized tomography (CT) scan is very diagnostic in the same patients.

Colon ischemia: Right-sided colon involvement has a different presentation, etiology and worse outcome. A large retrospective cohort study in histology proven patients

BACKGROUND

Colon ischemia (CI), is generally considered a non-occlusive mesenteric ischemia disorder that usually runs a benign course, but right-sided involvement (RCI) has been associated with worse outcome. The poor outcome of RCI has been associated with comorbidity, but more recently also with occlusions of the mesenteric arteries. We performed a retrospective analysis of a large cohort of CI-patients to assess differences in presentation, etiology, and comorbidity between right-sided colon ischemia (RCI) and non-right-sided colon ischemia (NRCI), and their relation to outcome.

METHODS

We performed a retrospective cohort study in two centers from 2000 to 2011 for CI and analyzed clinical presentation, etiology, treatment and outcome. Diagnosis was based on full colonoscopy and/or surgical findings and confirmed by histopathology.

RESULTS

239 patients were included (mean age 69, 52% female). RCI was found in 48% and NRCI in 52%. Patients with NRCI presented more often with rectal bleeding (87% vs. 45%; p<0.001). In RCI more nausea (58% vs. 39%; p=0.013), weight loss (56% vs. 19%; p<0.001), paralytic ileus (32% vs. 18%; p=0.018) and peritoneal signs (27% vs. 7%; p<0.001) was observed compared to NRCI. The cause of CI was more often idiopathic in NRCI (46% vs. 26%; p=0.002); an occlusive cause was seen more often in RCI (26.3 vs 2.4%, p<0.0001). RCI patients had longer hospital stay (15 vs. 8 days, p<0.001), need for surgery (61% vs. 34%, p<0.001), and trend toward higher 30-day in-hospital mortality (20% vs. 12%, p=0.084).

CONCLUSIONS

RCI ischemia has different etiology, presentation, and outcome. The series shows a high proportion of - treatable - vessel occlusion. It reinforces the advice to perform CT angiography in RCI as means to improve its poor outcome.

The predictors of the severity of ischaemic colitis: a systematic review of 2823 patients from 22 studies

AIM

The study reviews the literature related to ischaemic colitis (IC) as the evidence base to identify factors predicting severity.

METHOD

A systematic review of the literature was conducted on the predictors of the severity of IC. Severe IC or adverse outcome of IC was defined as a patient requiring surgery or who died. MEDLINE, Embase and Cochrane Library databases were searched from inception to 15 January 2015. Manual searches of reference lists from potentially relevant papers and meetings were also performed.

RESULTS

In all, 22 studies involving 2823 patients were identified; 19 were case series, two were case-control studies and one was a cohort study. The overall adverse outcome rate was 22.0% (620/2823). The prognostic predictors for surgery or mortality which were most frequently reported included right sided IC, peritonitis, shock or arterial hypotension (< 90 mmHg), male gender, tachycardia and lack of rectal bleeding. Thirteen studies relating to the right colon from which data could be extracted were further analysed. The right colon was involved in 277 cases, with an incidence of adverse outcomes of 48.4% (134/277), while in the non-right colonic involvement group the incidence was significantly lower at 12.1% (142/1175) (P = 0.000).

CONCLUSION

The incidence of adverse outcome in patients with IC remains high. Male gender, tachycardia, lack of rectal bleeding, peritonitis, shock or arterial hypotension (< 90 mmHg) and right sided IC are predictors of poor prognosis. Right-sided IC, shock or arterial hypotension (< 90 mmHg) and signs of peritonitis may be the most significant predictors of severity.

What is the predictor of surgical mortality in adult colorectal perforation? The clinical characteristics and results of a multivariate logistic regression analysis

PURPOSE

Colorectal perforations are a serious condition associated with a high mortality. The aim of this study was to describe the clinical characteristics and identify predictors for the surgical mortality in adult patients with colorectal perforation, thereby achieving better outcomes.

METHODS

A retrospective study of adult patients diagnosed with colorectal perforation operated was performed. The clinical variables that might influence the surgical mortality were first analyzed, and the significant variables were then analyzed using a logistic regression model.

RESULTS

A total of 423 patients were identified, and the surgical mortality rate was 36.9 %. The most common etiology was diverticulitis (38.2 %). The highest etiology-specific mortality was for colorectal cancer (61.5 %) and ischemic proctocolitis (59.8 %). In a logistic analysis, the significant predictors for the surgical mortality were ≥3 comorbidities (p = 0.034), preoperation American Society of Anesthesiologists score ≥4 (p = 0.025), preoperative sepsis or septic shock (p < 0.001), colorectal cancer or ischemic proctocolitis (p = 0.035), reoperation (p = 0.041), and Hinchey classification grade IV (p = 0.024).

CONCLUSION

We demonstrated that ≥3 comorbidities, a preoperation American Society of Anesthesiologists score ≥4, preoperative sepsis or septic shock, colorectal cancer or ischemic proctocolitis, reoperation, and Hinchey classification grade IV are predictors for the surgical mortality in the adult cases of colorectal perforation. These predictors should be taken into consideration to prevent surgical mortality and to reduce potentially unnecessary medical expenses.

Predictive Factors for Severe Outcomes in Ischemic Colitis

Background/Aims

Ischemic colitis includes a wide clinical spectrum ranging from mild to severe forms. This study aimed to determine the factors that are related to the occurrence of severe ischemic colitis.

Methods

This multicenter study was conducted retrospectively in Korea. The patients were divided into mild and severe groups. This study surveyed clinical characteristics, blood tests, endoscopic findings, and imaging studies.

Results

In the comparison of comorbidities, the severe group had a higher ratio of chronic kidney disease than the mild group (p=0.001). In the blood test, the severe group had a reduced number of platelets (p=0.018) and a higher C-reactive protein value (p=0.001). The severe group had a higher ratio of involvement of the right colon (p=0.026). The Eastern Cooperative Oncology Group (ECOG) performance status score of the patients showed that the severe group had higher scores than the mild group (p=0.003). A multivariate analysis showed that chronic kidney disease and high ECOG performance status scores were significant risk factors.

Conclusions

If patients diagnosed with ischemic colitis are also treated for chronic kidney disease or have poor performance status, more attention and early intervention are necessary.

Radiological Evaluation of Bowel Ischemia

Intestinal ischemia, which refers to insufficient blood flow to the bowel, is a potentially catastrophic entity that may require emergent intervention or surgery in the acute setting. Although the clinical signs and symptoms of intestinal ischemia are nonspecific, computed tomography (CT) findings can be highly suggestive in the correct clinical setting. In our article, we review the CT diagnosis of arterial, venous, and nonocclusive intestinal ischemia. We discuss the vascular anatomy, pathophysiology of intestinal ischemia, CT techniques for optimal imaging, key and ancillary radiological findings, and differential diagnosis.

"Cat scratch colon" in a patient with ischemic colitis

"Cat scratch colon" is a gross finding characterized by hemorrhagic mucosal scratches on colonoscopy. It is usually associated with a normal colon and is rarely associated with collagenous colitis. In a previous report, cat scratch colon was noted in the cecum and ascending colon, but has also been observed in the distal transverse colon. The patient in this study was also diagnosed with ischemic colitis that may have played a role in the development of cat scratch colon.

Natural history of outpatient-onset ischemic colitis compared with other lower gastrointestinal bleeding: a long-term cohort study

PURPOSES

The long-term clinical course of outpatient-onset ischemic colitis remains unknown. Our aims are to elucidate the in- and out-of-hospital clinical outcomes of ischemic colitis and compare them with those of lower gastrointestinal bleeding (LGIB).

METHOD

A cohort of 370 outpatients was hospitalized for ischemic colitis (n = 57) or other LGIB (n = 313). All patients had undergone colonoscopy. During hospitalization, the need for transfusion or interventions, further bleeding, mortality, and length of hospital stay were measured. After discharge, long-term recurrence and mortality were analyzed by the Kaplan-Meier method.

RESULTS

Colonoscopy revealed that 88% of ischemic colitis cases were left sided. Compared with other LGIB, ischemic colitis cases had significantly lower transfusion requirements (p < 0.01), further bleeding (p = 0.02), endoscopic intervention (p < 0.01), and shorter hospital stay (p = 0.03). No significant differences between the groups were noted in the need for surgery, angiographic procedures, or mortality during hospitalization. During a mean follow-up of 22 months, rebleeding was significantly lower (log-rank test; p < 0.01) in ischemic colitis cases (5.3%) than in other LGIB cases (19.4%) after discharge. During the mean follow-up period of 29 months, 1 patient (1.8%) with ischemic colitis and 18 patients (5.8%) with other LGIB died (log-rank test; p = 0.41).

CONCLUSIONS

Outpatient-onset ischemic colitis patients usually had left-sided colitis, recovered with conservative short-term treatment and had lower transfusion requirements and further bleeding compared with other LGIB patients. After discharge, patients with outpatient-onset ischemic colitis had lower recurrence over the long term than other LGIB patients.

The effects of vardenafil and pentoxifylline administration in an animal model of ischemic colitis

OBJECTIVES

Vardenafil enhances dilatation of vascular smooth muscle and inhibits platelet aggregation. The purpose of this study was to evaluate the clinical effects of vardenafil and pentoxifylline administration in an experimental model of ischemic colitis.

METHODS

Forty female Wistar albino rats weighing 250-300 g were randomized into five experimental groups (each with n = 8) as follows:1) a sham group subjected to a sham surgical procedure and administered only tap water; 2) a control group subjected to a standardized surgical procedure to induce ischemic colitis and administered only tap water; 3) and 4) treatment groups subjected to surgical induction of ischemic colitis followed by the postoperative administration of 5 mg/kg or 10 mg/kg vardenafil, respectively; and 5) a treatment group subjected to surgical induction of ischemic colitis followed by postoperative administration of pentoxifylline at 50 mg/kg/day per day as a single dose for a 3-day period. All animals were sacrificed at 72 h post-surgery and subjected to relaparotomy. We scored the macroscopically visible damage, measured the ischemic area and scored histopathology to determine the severity of ischemia. Tissue malondialdehyde levels were also quantified.

RESULTS

The mean Gomella ischemic areas were 63.3 mm2 in the control group; 3.4 and 9.6 mm2 in the vardenafil 5 and vardenafil 10 groups, respectively; and 3.4 mm2 in the pentoxifylline group (p = 0.0001). The mean malondialdehyde values were 63.7 nmol/g in the control group; 25.3 and 25.6 nmol/g in the vardenafil 5 and vardenafil 10 groups, respectively; and 22.8 nmol/g in the pentoxifylline group (p = 0.0001).

CONCLUSION

Our findings indicate that vardenafil and pentoxifylline are effective treatment options in an animal model of ischemic colitis. The positive clinical effects produced by these drugs are likely due to their influence on the hemodynamics associated with vascular smooth muscle and platelet functions.

Ischaemic colitis: indications, extent, and results of standardized emergency surgery

BACKGROUND

Acute ischaemic colitis can occur postoperatively, mainly after aortic surgery, or spontaneously. Surgical treatment is debated. Study aim was to describe factors related to ischaemic colitis severity, determine if postoperative and spontaneous ischaemic colitis share similar outcomes, and evaluate results of standardized management.

METHODS

191 consecutive cases of ischaemic colitis observed from 1997 to 2012 were retrospectively analyzed: 119 (62%) after surgery and 72 (38%) spontaneous. Colon resection was performed for endoscopic type 2 colitis with multiple organ failure, and for every type 3. Types 1 and 2 without multiple organ failure were managed nonoperatively.

RESULTS

Seventeen patients (9%) were managed nonoperatively, without mortality. Mortality rate after resection was 48% (84/174), within 9 days (range, 0-152). Multivariate analysis found 2 independent factors associated with postoperative death: age≥75 years and multiple organ failure. The context in which ischaemic colitis occurred was not a risk factor for mortality. Mortality rates were 51% for final type 3 (66% with multiple organ failure, 17% without), 53% for final type 2 with multiple organ failure, and 0% for type 1 or type 2 without multiple organ failure.

CONCLUSION

An aggressive surgical approach in patients with ischaemic colitis seems justified in patients with multiple organ failure and findings of severe form of ischaemia at endoscopy.

Surgery for ischemic colitis: outcome and risk factors for in-hospital mortality

PURPOSE

Surgery for ischemic colitis is associated with high perioperative morbidity and mortality, but the risk factors for mortality and major surgical complications are unclear.

METHODS

In this retrospective single institution cohort study of all patients undergoing colorectal surgery for histologically proven ischemic colitis between 2004 and 2010, we evaluated surgical outcomes and risk factors for in-hospital mortality and major surgical complications.

RESULTS

For the 100 patients included in the study, in-hospital mortality was 54 %; major surgical complications, defined as anastomotic leakage or rectal stump and stoma complications, occurred in 16 %. In the multivariable analysis, hospital death was more likely in patients with right-sided (odds ratio [OR] 3.8; 95 % confidence interval [CI] 1.2, 12; P = 0.022) or pan-colonic ischemia (OR 11; 95 % CI 2.8, 39; P < 0.001), both relative to left-sided ischemia. Decreased preoperative pH level (OR 2.5 per 0.1 decrease; 95 % CI 1.5, 4.1; P < 0.001) and prior cardiac or aortic surgery (OR 2.4; 95 % CI 0.82, 6.8; P = 0.109) were further important risk factors for in-hospital mortality. Major postoperative surgical complications were more likely in patients with ischemic alterations at the resection margin of the histological specimen (OR 3.7; 95 % CI 1.2, 11; P = 0.022).

CONCLUSIONS

Colonic resection for ischemic colitis is associated with high in-hospital mortality, especially in patients with right-sided or pan-colonic ischemia. In patients developing acidosis, early laparotomy is essential. Since resection margins' affection seems to be underestimated upon surgery, resections should be performed wide enough within healthy tissue.

Acute mesenteric ischemia: a sequela of abdominal aortography

The use of abdominal angiography and transcatheter embolization has increased rapidly in the last few decades. Although improvement in angiographic techniques has made the procedure safe, ischemic colitis is a rare but potentially dreadful complication. We report a case of a 51-year-old woman who developed ischemic colitis following aortography, demonstrating that such angiographic studies may produce substantial morbidity.

Management of ischemic colitis

Ischemic colitis is a commonly misunderstood clinical condition. Although the colon is the most common region of ischemia in the gastrointestinal tract, many surgeons have difficulty with diagnosis and treatment of ischemic colitis. The process can occur from either occlusive vascular disease or nonocclusive disease, and can be gangrenous or nongangrenous. Differentiating gangrenous from nongangrenous disease can be a difficult clinical challenge as both sets of patients generally present with abdominal pain and bloody diarrhea. Although the majority of patients have transient ischemia with nongangrenous colitis that can be successfully managed nonoperatively, prompt recognition and surgical intervention is critical in patients with gangrenous colitis. In this article, the diagnosis and treatment of ischemic colitis is reviewed with emphasis on a systematic, evidence-based approach to management.

Retrospective analysis of disease association and outcome in histologically confirmed ischemic colitis

OBJECTIVE

To identify risk factors, clinical features and complications in patients with ischemic colitis (IC).

METHODS

All patients diagnosed with biopsy proven IC within a 2-year period were identified; clinical data were retrospectively collected and subsequently analyzed.

RESULTS

In total, 72 IC patients with a mean age of 68 years were included in this study. Among them, 18 (25.0%) were younger than 65 years with a female predominance. One-third of the patients was found to be without vascular risk factors, and 8 patients met the criteria for irritable bowel syndrome. No history of oral contraceptives or hormonal replacement therapy use could be found among the women diagnosed with IC. Over a mean duration of follow-up of 9.5 months (range 0-65 months), the rate of recurrent disease was 16.7%, while only 2 (2.8%) patients developed extra intestinal vascular sequelae. Statistical analysis identified a history of atrial fibrillation and the use of furosemide to be the only significant predictors of a poor outcome, while coronary artery disease and chronic renal failure predicted recurrence and low platelet count predicted stricture formation.

CONCLUSIONS

Although most patients with IC are elderly and have conventional vascular risk factors, it should also be considered in young patients without vascular risk factors, especially in women, who may have an atypical distribution of the disease. Severe complications and extraintestinal vascular sequelae are rare, however, residual gastrointestinal complaints and recurrent disease are relatively common and there are no reliable predictors of the outcome.

Ischemic colitis: the ABCs of diagnosis and surgical management

Ischemic colitis (IC) is a rare condition. As ischemia is often transient and clinical symptoms are reversible, its exact incidence is unknown. In current clinical practice, two types of IC are described according to the severity: severe IC, with transmural colonic ischemia and/or multi-organ failure (MOF), and mild IC, without MOF and spontaneous favourable evolution in most cases. Two clinical contexts are encountered: spontaneous IC (SIC) and postoperative IC (POIC), mainly after aortic surgery. As there is no specific clinico-biologic symptom of IC, emergent CT-scan and rectosigmoidoscopy are required for diagnosis confirmation, surgical decision and prognosis analysis. IC surgical treatment is not consensual but can be standardized according to organ function and the degree of ischemia: surgical treatment in case of colonic necrosis with deep ischemia and/or MOF; observation for superficial ischemia without organ dysfunction; systematic medical care. Surgery is required in 20% of cases, and consists in extended colectomy without continuity restoration and prophylactic cholecystectomy. Continuity restoration is feasible in one third of survivors, who are exposed to a high risk of severe cardiovascular events.

Branching pattern of inferior mesenteric artery in a black african population: a dissection study

Background. Branching pattern of inferior mesenteric artery (IMA) and pattern of vascular supply to the left colon and rectosigmoid areas, though important during colorectal surgery, display interethnic variations. Further, these regions have notable vascular "weak points" reported to be highly susceptible to ischemic colitis. This study aimed at evaluating the branching pattern of IMA in a black African population. Materials and Methods. Fifty-seven formalin-embalmed cadavers (28 Male, 27 Female) were studied. The length, branching pattern, and diameter of IMA at its origin were recorded. Results. IMA mean length and diameter at origin were 30.57 ± 10.0 mm and 4.10 ± 0.9 mm, respectively. IMA most frequently branched into left colic artery and a common sigmoid trunk in 23 cases while the classical branching pattern was observed in only 7 cases. Colic marginal artery was absent at the splenic flexure and sigmoid colon in 7 and 5 cases, respectively. Arc of Riolan was observed in 9 cases. Conclusion. Branching pattern of IMA shows variations from the previously reported cases which might help account for some of the untoward outcomes observed following colon surgery. An angiographic study to further delineate functionality of the arterial anastomoses in this region is recommended.

Systematic review of the management of ischaemic colitis

AIM

The study reviews the literature related to ischaemic colitis (IC) to establish an evidence base for its management and to identify factors predicting severity and mortality.

METHOD

A systematic review of the English language literature was conducted according to recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. MEDLINE, Embase and Cochrane Library databases were searched using the keyword search 'ischaemic colitis OR colon ischaemia OR colonic ischaemia OR management ischaemic colitis'. IC is often misdiagnosed so only studies where the diagnosis was supported by histopathology in every case were included. Critical appraisal was performed of included studies using predefined quality assessment checklists and narrative data synthesis.

RESULTS

In all, 2610 publications were identified. Of these, eight retrospective case series and three case controlled studies describing 1049 patients were included. Medical management was used in 80.3% patients of whom 6.2% died. Surgery was required in 19.6% of whom 39.3% died. The overall mortality of IC was 12.7%. Lack of rectal bleeding, peritonism and renal dysfunction were commonly quoted predictors of severity; however, right sided IC appeared to be the most significant predictor of outcome.

CONCLUSION

Most patients with IC can be managed conservatively. Right sided IC may be the most significant predictor of severity.

Stenotic ischemic colitis treated with laparoscopy-assisted surgery

Ischemic colitis is the most common type of intestinal ischemia. The etiology of this condition is multifactorial, and the diagnosis is based on a combination of clinical symptoms, as well as endoscopic and histological findings. Although conservative therapy is effective in most cases, surgery still plays a key role in the treatment of ischemic colitis. Here, we describe a case of a 73-year-old man in whom laparoscopy-assisted left colectomy was performed 80 d after the onset of ischemic colitis. He recovered completely after surgery, and the pathological findings were consistent with ischemic colitis. To the best of our knowledge, there are no detailed reports of laparoscopic surgery for chronic segmental stenotic ischemic colitis. We discussed the usefulness of laparoscopic surgery, comparing it with endoscopic treatment, and we propose an optimal treatment strategy from a viewpoint of stenosis length and duration of disease.

The Differential Diagnosis of Colitis in Endoscopic Biopsy Specimens: A Review Article

Context.—A variety of inflammatory disorders may affect the colon, with widely differing clinical outcomes and management. These conditions encompass a spectrum of acute and chronic conditions.

Objective.—Review the pathology of the major colitides and highlight the most diagnostically useful features.

Data Sources.—Review of recent literature supplemented with personal experience in the field of gastrointestinal pathology.

Conclusions.—The etiologies associated with the various types of colitis are diverse and the range of histologic changes is somewhat limited. Nevertheless, the combination of clinical and endoscopic data coupled with histopathology allows for accurate classification in the majority of cases.

Adverse drug reaction: rosuvastatin as a cause for ischaemic colitis in a 64-year-old woman

Rosuvastatin (Crestor, AstraZeneca) is a commonly used drug for managing hypercholesterolaemia. It is a very safe medication with mostly acceptable side effects. Rare but serious side effects are not well known. A 64-year-old woman presented with bloody diarrhoea after starting rosuvastatin for hypercholesterolaemia. Stool microscopy and culture ruled out infective causes. Abdominal CT scan revealed normal calibre celiac axis and superior mesenteric artery. Colonoscopic biopsy revealed ischaemic colitis as the final histological diagnosis. The patient is in complete remission after ceasing the medication. Rosuvastatin causing ischaemic colitis should be considered a rare but serious adverse drug reaction.

Clinical characteristics of young-onset ischemic colitis

BACKGROUND

Ischemic colitis (IC) typically develops in the elderly, where hypertension, cerebrocardiovascular disease, and past history of abdominal surgery are regarded as risk factors. Although there have been reports of younger patients with IC, its clinical features remain unclear.

AIM

The aim of this study was to clarify the clinical characteristics of IC in young adults.

METHODS

Three hundred fifty-nine patients were diagnosed as having IC at five hospitals across Nagano prefecture, Japan. Clinical data were compared between the young patient group [20-45 years, n = 53 (15%)] and the elderly patient group [>45 years, n = 306 (85%)], as well as with age- and gender-matched healthy individuals (n = 156).

RESULTS

The presence of a smoking habit and hyperuricemia were significantly higher in the young patient group compared with the elderly patient group (42 vs. 19%, P = 0.001 and 8 vs. 1%, P = 0.019, respectively), which was confirmed by multiple logistic regression analysis (P = 0.001, odds ratio 3.239 and P = 0.028, odds ratio 16.907, respectively). Additionally, multiple logistic regression analysis of the young IC patient group and age- and gender-matched healthy individuals demonstrated that these two factors were strongly associated with IC development (P = 0.008, odds ratio 2.49 for smoking habit and P = 0.039, odds ratio 6.37 for hyperuricemia).

CONCLUSIONS

High prevalences of a smoking habit and hyperuricemia are characteristic features of IC in the young adult population.

Ischemic colitis: clinical presentation, localization in relation to risk factors, and long-term results

BACKGROUND

Ischemic colitis is commonly thought to occur most often in the left hemicolon close to the splenic flexure owing to insufficient blood supply near Griffith's point. This study investigates the colorectal localization pattern, the risk factors, and the long-term outcome of histologically proven ischemic colitis.

METHODS

Between 1996 and 2004, a total of 49 patients with a median age of 69 years (range 26-94 years) with colonoscopically assessed and histologically proven ischemic colitis were identified on behalf of the pathology database. Long-term results of 43 patients were evaluated retrospectively after a median interval of 79 months (range 6-163 months).

RESULTS

In 27 patients (55%) more than one location was affected. We found 98 affected locations in 49 patients. The distribution of ischemic colitis in our group shows no significantly preferred location. In an exploratory analysis, the cecum, ascending colon, and right flexure were affected significantly more often if intake of a nonsteroidal antiinflammatory drug (NSAID) is documented. There was no association between the location of ischemic colitis and a history of smoking, peripheral artery occlusive disease, coronary heart disease, diabetes, or malignant tumor.

CONCLUSIONS

Ischemic colitis seems not to have a predisposing site of occurrence in the colorectum, especially Griffith's point which was not afflicted significantly more often than other sites. Frequently, ischemic colitis afflicts more than one colonic location. In patients being treated with NSAIDs, ischemic colitis was observed significantly more often in the right hemicolon. Recurrence of ischemic colitis seems to be rare.

Predictors of severity in ischaemic colitis

PURPOSE

Ischaemic colitis (IC) is an inadequate perfusion leading to potentially life-threatening colonic inflammation. The aim was to identify patient characteristics that predict severity in biopsy-confirmed IC.

METHODS

A retrospective study of consecutive patients admitted with a robust diagnosis of IC over a 5-year period was performed. As IC is often misdiagnosed, strict inclusion criteria including supporting histopathology, exclusion of inflammatory bowel disease, absence of recent antibiotics or negative stool sampling with testing for Clostridium difficile were adhered to. Due to differing pathophysiology involved, patients suffering IC due to injury to colonic perfusion from vascular procedures or tumours were also excluded. Patients were divided by outcomes into a severe IC group including those that needed surgery or suffered mortality and a non-severe IC group that included patients managed medically with good evolution during their index admission. Patient characteristics were analysed to identify statistically significant predictors of severity (p < 0.05).

RESULTS

Thirty-two patients (11 males, 21 females; mean age 72.5) met the inclusion criteria. Medical management was adopted in 23 patients with a single mortality (4.3%). Nine patients were managed surgically with two mortalities (22.2%), giving an overall mortality of 9.4% and a severe IC group consisting of ten patients. Significant prognostic predictors of severity included: right-sided IC (p = 0.0002), guarding (p = 0.001), lack of bleeding per rectum (p = 0.005) and chronic constipation (p = 0.02).

CONCLUSIONS

The majority of patients with IC can be managed conservatively. Right-sided IC, guarding, lack of bleeding per rectum and chronic constipation are associated with severe IC.

Ischemic colitis masquerading as colonic tumor: Case report with review of literature

Ischemic colitis can mimic a carcinoma on computed tomographic (CT) imaging or endoscopic examination. A coexisting colonic carcinoma or another potentially obstructing lesion has also been described in 20% of the cases of ischemic colitis. CT scan can differentiate it from colon cancer in 75% of cases. However, colonoscopy is the preferred method for diagnosing ischemic colitis as it allows for direct visualization with tissue sampling. Varied presentations of ischemic colitis have been described as an ulcerated or submucosal mass or as a narrowed segment of colon with ulcerated mucosa on colonoscopy. Awareness and early recognition of such varied presentations of a common condition is necessary to differentiate from a colonic carcinoma, and to avoid unnecessary surgery and related complications.

Systematic review on the treatment of ischaemic colitis

AIM

Ischaemic colitis is uncommon. Aetiological factors include abdominal aortic surgery, drugs (especially inotropics) or rheumatoid diseases, such as Takayasu's or Buerger's diseases. However, there is often no triggering factor, and it may be part of multifactorial cardiac, respiratory, renal or metabolic failure.

METHOD

A systematic review of the current literature on the management of ischaemic colitis was carried out.

RESULTS

Ten retrospective trials (841 patients) were included. No randomized controlled or prospective trial of the management of ischaemic colitis was found.

CONCLUSION

There is very little evidence base for the management of this condition.

Clinical patterns and outcomes of ischaemic colitis: results of the Working Group for the Study of Ischaemic Colitis in Spain (CIE study)

BACKGROUND

There is a lack of prospective studies evaluating the natural history of colonic ischaemia (CI). We performed such a study to evaluate the clinical presentation, outcome, and mortality as well as clinical variables associated with poor prognosis.

METHODS

An open, prospective, and multicentre study was conducted in 24 Spanish hospitals serving a population of 3.5 million people. The study included only patients who met criteria for definitive or probable CI. A website (www.colitisisquemica.org) provided logistical support.

RESULTS

A total of 364 patients met criteria for inclusion. CI was suspected clinically in only 24.2% of cases. The distribution of clinical patterns was as follows: reversible colopathy (26.1%), transient colitis (43.7%), gangrenous colitis (9.9%), fulminant pancolitis (2.5%), and chronic segmental colitis (17.9%). A total of 47 patients (12.9%) had an unfavorable outcome as defined by mortality and/or the need for surgery. Multivariate analysis identified the following signs as independent risk factors for an unfavorable outcome: abdominal pain without rectal bleeding [odds ratio (OR) 3.9; 95% confidence interval (CI) = 1.6-9.3], non-bloody diarrhoea (OR 10; 95% CI = 3.7-27.4), and peritoneal signs (OR 7.3; 95% CI = 2.7-19.6). Unfavorable outcomes also were more frequent in isolated right colon ischaemia (IRCI) compared with non-IRCI (40.9 vs. 10.3%, respectively; p < 0.0001). The overall mortality rate was 7.7%.

CONCLUSIONS

The clinical presentation of CI is very heterogeneous, perhaps explaining why clinical suspicion of this disease is so low. The presence of IRCI, and occurrence of peritoneal signs or onset of CI as severe abdominal pain without bleeding, should alert the physician to a potentially unfavorable course.

Multidetector CT imaging in mesenteric ischemia--pearls and pitfalls

Mesenteric ischemia is a complex and devastating disease which still remains a diagnostic challenge to the clinicians due to non-specific clinical and laboratory findings. Several imaging features have been described with multidetector computed tomography which allows the diagnosis of mesenteric ischemia with high sensitivity and specificity. However, there are imaging features which overlap with other pathologies including benign inflammation and infection. Knowledge of imaging findings in mesenteric ischemia and its potential mimics is important in early and definitive diagnosis.

Morbidity and mortality following colorectal surgery in patients with end-stage renal failure: a population-based study

PURPOSE

The risk of abdominal surgery in patients with end-stage renal failure is poorly defined. Our objective was to describe outcomes of colorectal surgery in dialysis patients from a population-based perspective.

METHODS

We analyzed the 1993 to 2007 Nationwide Inpatient Sample to identify patients hospitalized for colorectal surgery. The effect of renal failure on mortality, complications, length of stay, and charges was evaluated using logistic regression models.

RESULTS

Between 1993 and 2007, there were 755,343 admissions for colorectal surgery in the Nationwide Inpatient Sample database; 5806 patients (0.77%) were receiving dialysis treatment (87.4% hemodialysis, 4.9% peritoneal dialysis, 7.7% method not specified). Patients undergoing dialysis had an increased risk of mortality (22.1% vs 2.8%; adjusted OR 4.83; 95% CI 4.58-5.31) and complications (52.1% vs 34.0%; adjusted OR 2.04; 95% CI 1.90-2.17). Dialysis patients undergoing nonelective procedures had a 2-fold higher mortality rate than patients having had elective surgery (25.5% vs 10.3%; adjusted OR 2.01; 95% CI 1.65-2.43). In nonelective surgery, independent predictors of mortality included procedures with an end-stoma (adjusted OR 1.86; 95% CI 1.58-2.18), age over 60 (adjusted OR 1.73; 95% CI 1.43-2.08), total colectomy (adjusted OR 1.68; 95% CI 1.27-2.22), vascular insufficiency as surgical indication (adjusted OR 1.58; 95% CI 1.32-1.90), nonprivate insurance coverage (adjusted OR 1.38; 95% CI 1.07-1.77) and malnutrition (adjusted OR 1.26; 95% CI 1.01-1.59).

CONCLUSIONS

Patients receiving dialysis treatment have an increased risk of morbidity and mortality following colorectal surgery. Elective procedures are associated with a 10% rate of mortality in this population. Dialysis patients are especially susceptible to infectious and pulmonary complications after colorectal resection. Additional studies are necessary to refine risk stratification in this high-risk patient population.

Anatomic patterns, patient characteristics, and clinical outcomes in ischemic colitis: a study of 313 cases supported by histology

OBJECTIVES

Previous reports on the anatomic portions of colon involved in cases of supposed ischemic colitis (IC) have been limited by the absence of confirmation of the true nature of the disease. This is the first anatomic study to define the patterns of colon involvement in which only cases with biopsy-proven or -compatible IC and in which the entire colon had been visualized at surgery or at colonoscopy were included. The aims of this study were to re-examine patterns of colonic involvement in IC using only cases in which the diagnosis was biopsy proven or compatible, and to examine the clinical features and outcomes with regard to the segments of colon involved.

METHODS

A retrospective study was undertaken of patients with IC who were hospitalized at Montefiore Medical Center from 1998 to 2009. Patients were identified using computerized searches of ICD-9 (International Classification of Diseases, ninth revision) codes for colon ischemia, and patterns of colon involvement were then tabulated and categorized into five major groups: right colon, transverse colon, left colon, distal colon, and pancolon involvement. Patterns were classified based on the most proximal location of injury. Major anatomic patterns were then subcategorized into more specific segments of involvement. Only biopsy-proven or -compatible cases of IC in which the entire colon had been visualized at surgery or at colonoscopy were used in this study.

RESULTS

A total of 313 cases of biopsy-proven or -compatible IC were identified. Patterns and frequencies of involvement were: right colon, 25.2%; transverse colon, 10.2%; left colon, 32.6%; distal colon, 24.6%; and pancolon, 7.3%. Compared with all other patterns of IC, the right colon pattern was more likely to be associated with coronary artery disease (39.2 vs. 21.4%) or end-stage kidney disease requiring dialysis (20.3 vs. 7.7%), a longer hospitalization (median stay, 10 vs. 6 days), a greater need for surgery (44.3 vs. 11.5%), and the highest mortality rate (20.3 vs. 9%). Patients with a left colon pattern were less likely to be operated upon, and had a shorter length of stay than any other pattern of IC. Hyperthyroidism, stroke, and chronic obstructive pulmonary disease (COPD) were statistically significant independent predictors of mortality.

CONCLUSIONS

IC is typically a segmental disease, flanked by normal colon on either side of the affected area. Comorbid disease associations and severity of disease as reflected by length of hospitalization, need for surgery, and mortality vary with the segment involved. IC isolated to the right side of the colon is a more severe disease than IC affecting any other segment of colon.

Development and validation of a novel prognostic scoring model for ischemic colitis

PURPOSE

This study was conducted to identify prognostic factors affecting the course of ischemic colitis and to develop a prognostic scoring model.

METHODS

We analyzed medical records of consecutive patients with ischemic colitis treated between October 2002 and September 2008 at Severance Hospital, Seoul, Republic of Korea. Patients were excluded if results of endoscopy were unavailable. Patients were classified as having severe ischemic colitis on the basis of outcome (improvement delayed for more than 2 weeks, complications requiring surgery, or death). Univariate analyses and multivariate logistic regression analyses with backward stepwise selection were used to identify clinical, endoscopic, and laboratory variables associated with severe ischemic colitis. A novel prognostic scoring model was derived from the data, with probability of severe ischemic colitis and risk index determined for 8 risk groups based on independent risk factors identified by multivariate analyses. Predictive power was tested by means of 10-fold cross-validation, with area under the receiver operating characteristic curve representing discrimination accuracy.

RESULTS

Analyzable data were available for 153 of 173 consecutive patients. Ischemic colitis was classified as severe in 20 patients. Multivariate analyses showed the following significant independent predictors of severe ischemic colitis: tachycardia (adjusted odds ratio = 4.6; 95% CI, 1.4-14.7), shock within 24 hours after admission (adjusted odds ratio = 6.5; 95% CI, 2.0-21.2), and endoscopic evidence of ulceration (adjusted odds ratio = 9.9; 95% CI, 2.0-48.8). Probability of severe ischemic colitis and risk index were 74 times higher for patients with all 3 risk factors (group 8) than for patients with none (group 1). Internal validation showed the area under the receiver operating characteristic curve to be 0.91 (95% confidence interval, 0.86-0.96).

CONCLUSIONS

Endoscopic findings and instability of vital signs were associated with the disease course of ischemic colitis. A novel scoring model based on presence of tachycardia, shock within 24 hours after admission, and endoscopic evidence of ulceration provides a method of assessing patient prognosis and should be further validated.

Male gender and renal dysfunction are predictors of adverse outcome in nonpostoperative ischemic colitis patients

OBJECTIVE

Ischemic colitis (IC) spans a broad spectrum from self-limiting illness to intestinal gangrene and mortality. Prognostic factors specifically for nonpostoperative IC were not fully characterized. We aim to focus on nonpostoperative IC in patients with renal dysfunction and try to identify prognostic factors for adverse outcomes.

METHODS

We conducted a retrospective analysis at a university-affiliated tertiary medical center in Taiwan. From January 2003 to August 2008, 25 men and 52 women (mean age: 66 y) had colonoscopic biopsy-proven IC without prior culprit surgery. We estimated glomerular filtration rate with simplified Modification of Diet in Renal Disease equation. Nine patients with glomerular filtration rate below 30 mL per minute per 1.73 m were classified as renal dysfunction group (including 7 dialysis patients). Adverse outcomes were defined as need for surgery and mortality. Predictors for adverse outcomes were captured by univariate and multivariate analysis. Research ethical committee approved the study protocol.

RESULTS

Patients with renal dysfunction more often had: diabetes mellitus (56% vs. 16%, P=0.02), prolonged symptoms (6.8 d vs. 3.5 d, P=0.01), lower hemoglobin (11.1 g/dL vs. 13.4 g/dL, P=0.01), and more often right colonic involvement (56% vs. 19%, P=0.03). Renal dysfunction patients also had longer hospitalization days (median 15 d vs. 4 d, P=0.045). However, there was no statistical significance in the rate of either surgery or mortality between these 2 groups (P>0.05). Univariate analysis showed that renal dysfunction, sex, emergency department referral, presentation with abdominal pain were significant for adverse outcome (P<0.1). Multivariate analysis revealed that male sex conveyed 9.5-fold risk (P=0.01) and renal dysfunction conveyed 8.5-fold risk (P=0.03) for adverse outcomes.

CONCLUSIONS

Nonpostoperative IC patients with concurrent renal dysfunction had distinct clinical profiles. Multivariate analysis showed that male patients had 9.5-fold and renal dysfunction patients had 8.5-fold increased risk for adverse outcomes. Although IC is often self-limited, our data warrants special attention and aggressive therapy in treating these patients.