Ischemic Colitis Group Research Articles

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

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

Ischemic Colitis Is a Risk Factor for Clostridium difficile Infection.

Introduction: Clostridium difficile infection (CDI) is an anaerobic infection that can carry detrimental outcomes for patients and is a growing burden to the US healthcare system. Various theories have been proposed for the etiopathogenesis of CDI, including antibiotic use, dysbiosis, and acid suppression. The role of ischemia in CDI has not been explored. We hypothesize that tissue ischemia is a risk factor for the development of CDI. The study aimed to assess whether ischemia was a risk factor for CDI using ischemic colitis as a target population.Methods: We performed a case-control study using the National Inpatient Sample (NIS) database in 2013. The study group included all patients with ischemic colitis (ICD 9 Code: 557.0, 557.1, 557.9) and the control group included all patients with diverticulitis (ICD 9 Code: 562.11, 562.13). Univariable and multivariable analyses were performed to assess the risk factors associated with CDI (ICD 9 Code: 008.45). The case and control groups were compared using the chi-square test for analysis. Continuous variables were compared using t-tests and categorical variables were compared using Rao-Scott chi-square tests. In addition, multivariable logistic regression analysis was performed to assess the association between disease group and CDI while adjusting for confounders. Univariable analysis was performed to assess differences between subjects with ischemic colitis and those with diverticulitis; continuous variables were compared using t-tests and categorical variables were compared using Rao-Scott chi-square tests. All analyses were done using SAS (version 9.4, The SAS Institute, Cary, NC).Results: We analyzed more than 30 million hospitalizations in 2013, with 120,490 being Ischemic colitis-related admissions and 309,940 being diverticulitis-related admissions. The rate of CDI was more in the ischemic colitis group than in the diverticulitis group (odds ratio [OR] = 1.39; 95% confidence interval [CI] [1.03-1.88], p=0.03). After adjusting for all variables, multivariate analysis showed CDI was associated with ischemic colitis (OR = 2.06; 95% CI 1.59-2.65, p<0.001).Conclusion: CDI was shown to be more prevalent in ischemic colitis than in diverticulitis control in this population-based study. As C. difficile is an anaerobe, we hypothesize that tissue hypoxia is a risk factor for its development. Further studies are needed to validate our findings.

Clinical features and risk factors for ischemic colitis in young and middle-aged patients.

Ischemic colitis (IC) is thought to occur more frequently in the elderly, but the incidence in young and middle-aged adults is increasing. This study determined the clinical characteristics of and risk factors for young and middle-aged IC patients. The medical records of 190 IC patients from 2010-2020 were reviewed. The clinical features of the young and middle-aged IC group (group A, < 60 years [n=70]) were compared to the elderly IC (group B, ≥60 years [n=120]) and age- and gender-matched colon polyp groups (group C, <60 years [n=272]). Independent risk factors for IC in group A were assessed using multivariate logistic regression analysis. There were no significant differences in groups A and B with respect to season of onset, symptoms, signs, treatment, or recurrences. The main symptoms of group A were abdominal pain (98.6%) and hematochezia (98.6%). Lesions commonly involved the left half of the colon (87.1%) and the clinical conditions were generally not severe. The percentage of patients with constipation (11.4% vs. 4.0%, P=0.034) and using a calcium channel antagonist (21.4% vs. 11.4%, P=0.028) was significantly higher in group A than group C. Regression analysis demonstrated that constipation (OR 2.831, P=0.037) and taking a calcium channel antagonist (OR 2.486, P=0.012) were closely associated with the occurrence of IC in group A. Constipation and taking a calcium channel antagonist were independent risk factors for the onset of IC in young and middle-aged adults. Among young and middle-aged adults with abdominal pain and bloody stools who also have constipation or are taking a calcium channel antagonist to treat hypertension, the diagnosis of IC should be considered.

Screening of serological markers for differential diagnosis ischemic colitis and ulcerative colitis by proteomic techniques

Objective To screen and identify serum protein biomarkers for the differential diagnosis between ischemic colitis (IC) and ulcerative colitis (UC) by tandem mass tag (TMT) combined with liquid chromatography/tandem mass spectrometry (LC-MS/MS). Methods From January 2018 to January 2019, at the First Affiliated Hospital of School of Medicine of Zhejiang University, patients with UC or IC, and health controls, each 10 cases, were enrolled into UC group, IC group and normal control (NC) group, respectively. Fasting serum samples of all the subjects were collected. After removal of high-abundance protein, followed by proteolysis, peptide labeling and fractionating, the samples were then processed by mass spectrometry. The protein with TMT data of three groups was obtained and protein with TMT value 0 were removed. Heat map of protein was constructed. The differential protein was defined as the protein fold change over 1.5 or less than 0.67. The Reactome database was used to cluster the pathways of differential proteins among groups. Statistical methods included t test, hypergeometry test and corrected by BH multiple test. Results A total of 357 serum proteins were identified by proteomic profiling. There were 27 differential proteins between the IC group and the NC group, including six up-regulated proteins and 21 down-regulated proteins. There were 228 differential proteins between the UC group and the NC group, including 75 up-regulated proteins and 153 down-regulated proteins. There were 49 differential proteins between UC group and IC group, including 22 up-regulated proteins and 27 down-regulated proteins. In the comparison of differential proteins between the NC group, IC group and UC group, only the expression of fibrin 3 was statistically significant (the fold change between UC and NC, between UC and IC, between IC and NC were 0.24, 0.46 and 0.53, respectively; t=-5.089, -7.298 and -3.919, all P<0.01). The results of pathway cluster analysis showed that in the comparison of differential proteins between IC group and NC group, only the platelet degranulation pathway was enriched, and 10 proteins were involved in this pathway (P<0.01). In the comparison of differential proteins between UC group and NC group, there were 58 pathways enriched, of which 38 proteins were involved in the platelet degranulation pathway, 16 proteins were involved in the initial complement trigger pathway, 13 proteins were involved in the complement cascade pathway, and 11 proteins were involved in antibody-mediated complement activation pathway (all P<0.01). In the comparison of differential proteins between UC group and IC group, three different pathways were obtained. Among them, nine proteins were involved in the platelet degranulation pathway, seven proteins were involved in the initial complement trigger pathway, and five proteins were involved in the complement cascade pathway (all P<0.01). Conclusions The difference in serum proteome between IC patients and UC patients was significant, and the differential proteins are mainly involved in platelet activation and complement activation. The candidate proteins identified in this study may be used as biomarkers for the differential diagnosis of UC and IC in the future. Key words: Colitis, ischemic; Colitis, ulcerative; Proteomics; Markers, serum

Predictors of severity in ischemic colitis: Usefulness of early ultrasonography

PurposeThe main objective was to evaluate the usefulness of early ultrasonography for determining prognosis of patients with ischemic colitis. Materials and methodsWe 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. ResultsThe 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. ConclusionsSonographic 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.

Ischemic Colitis after Cardiac Surgery: Can We Foresee the Threat?

IntroductionIschemic colitis (IC) remains a great threat after cardiac surgery with use of extracorporeal circulation. We aimed to identify predictive risk factors and influence of early catecholamine therapy for this disease.MethodsWe prospectively collected and analyzed data of 224 patients, who underwent laparotomy due to IC after initial cardiac surgery with use of extracorporeal circulation during 2002 and 2014. For further comparability 58 patients were identified, who underwent bypass surgery, aortic valve replacement or combination of both. Age ±5 years, sex, BMI ± 5, left ventricular function, peripheral arterial disease, diabetes and urgency status were used for match-pair analysis (1:1) to compare outcome and detect predictive risk factors. Highest catecholamine doses during 1 POD were compared for possible predictive potential.ResultsPatients’ baseline characteristics showed no significant differences. In-hospital mortality of the IC group with a mean age of 71 years (14% female) was significantly higher than the control group with a mean age of 70 (14% female) (67% vs. 16%, p<0.001). Despite significantly longer bypass time in the IC group (133 ± 68 vs. 101 ± 42, p = 0.003), cross-clamp time remained comparable (64 ± 33 vs. 56 ± 25 p = 0.150). The majority of the IC group suffered low-output syndrome (71% vs. 14%, p<0.001) leading to significant higher lactate values within first 24h after operation (55 ± 46 mg/dl vs. 31 ± 30 mg/dl, p = 0.002). Logistic regression revealed elevated lactate values to be significant predictor for colectomy during the postoperative course (HR 1.008, CI 95% 1.003–1.014, p = 0.003). However, Receiver Operating Characteristic Curve calculates a cut-off value for lactate of 22.5 mg/dl (sensitivity 73% and specificity 57%). Furthermore, multivariate analysis showed low-output syndrome (HR 4.301, CI 95% 2.108–8.776, p<0.001) and vasopressin therapy (HR 1.108, CI 95% 1.012–1.213, p = 0.027) significantly influencing necessity of laparotomy.ConclusionPatients who undergo laparotomy for IC after initial cardiac surgery have a substantial in-hospital mortality risk. Early postoperative catecholamine levels do not influence the development of an IC except vasopressin. Elevated lactate remains merely a vague predictive risk factor.

Ischemic Colitis Affects Descending Colon More and Cecum Less Often in Females Compared to Males

Introduction: Ischemic colitis (IC) has been increasingly diagnosed with advancement in medicine. However, gender differences have not been studied previously in IC. The aim of this study was to investigate the characteristics of IC in female compared to male patients. Methods: We reviewed medical records of patients with IC from January 2007 to January 2013 in two hospitals after IRB approval. Demographic details, clinical & lab data, imaging, endoscopy & histology, comorbidities, concomitant medications, surgery, length of hospital stay & death within 30 days of admission, were collected. The patients were divided into two groups: female IC group and male IC group. The diagnosis of IC was made based on clinical features consistent with IC with negative stool studies for infections & at least one diagnostic study consistent with IC (CT scan, colonoscopy, or histology). Exclusion criteria: age < 18, pregnancy, positive studies for gut pathogens, colonic ischemia due to trauma or mechanical causes, chronic bowel ischemia, acute flare of IBD & evidence of diverticulitis. Results: A total of 118 patients with IC were identified (mean age 69.4±15.07 years, 83.1% female). The clinical presentation, laboratory features, radiological findings, comorbidities, and use of 12 categories of commonly used medications were not different between both groups (p >0.05 for all variables). While the descending colon was affected more often in the female IC group (71.7% vs. 40%, p=0.007), the cecum was affected more often in the male IC group (8.1% vs. 25%, p=0.039). Colonoscopy was performed in 75.4% of patients; the findings of erosions or ulcerations in the affected colonic areas were more often seen in females compared to males (59.2% vs. 29.4%, p=0.027). Although, numerically, IC in males was worse in terms of the need for surgical interventions, ICU admission, mechanical ventilation, length of hospital stay, and death within 30 days, no statistically significant difference was observed (p >0.05 for all variables). Conclusion: The descending colon was affected more often in females, whereas the cecum was affected more often in males with IC. Erosions and ulcerations were seen more often in females. The outcomes of IC in males tend to be worse than females but were not significantly different. Larger studies are needed to further elucidate the gender differences in IC.

Mo2021 The Role of Hypercoagulability in Ischemic Colitis

Introduction: Ischemic colitis (IC) is one of the most common gastrointestinal vascular diseases in the world. IC can result from alterations in the systemic circulation or from anatomic or functional changes in the mesenteric vasculature. On the other hand, an increasing diversity of causes of IC has been reported, including hematologic disorders, thrombophilic conditions, and medications. The aim of this study is to evaluate the role of thrombophiliahypercoagulability in IC. Methods: A prospective study of 56 patients with IC (diagnosis was established from clinical, endoscopic and pathologic (biopsy proven or compatible with IC) findings) who were evaluated for protein C (PC), protein S (PS), antithrombin (AT), resistance to activated protein C (APCR), lupus anticoagulant (LA), factor V G1691Amutation (FV Leiden), prothrombin G20210A mutation, methylenetetrahydrofolate reductase (MTHFR) gene C677T & A1298C mutations and plasminogen activator inhibitor-1 (PAI1) gene 5G/4G & 4G/4G polymorphisms. The results were compared with 44 controls with known predisposing factors (including history of thrombosis, atherosclerosis, hypertension, chronic renal insufficiency, diabetes mellitus, irritable bowel syndrome, chronic constipation, history of abdominal aorta aneurysm, history of schock and autoimmune disease) but no evidence of IC. Results: Low levels of PC and AT (p= .064 & p= .022, respectively), low levels of APCR (normal: >2, p = .008) and high levels of fibrinogen (p= .0005) were recorded in IC group. Homozygotes for MTHFR A1298C & C677T mutations tended to be more in the group with IC (χ2(2)= 5.582, p = .061 & χ2(2)= 1.291, p= .525, respectively). Furthermore, the prevalences of 5G/4G & 4G/4G polymorphisms were elevated in the patients group (χ2(2)= 6.973, p = .031), while the incidence of LA positives was higher in the same group (p = .037, FET). Multivariate analysis was performed to determine the effects of prothrombotic factors in IC. 5G/4G polymorphism of PAI-1 gene (OR 12.29; 95% CI 2.2667.00), APCR (OR .089; 95% CI 0.011-0.699) and fibrinogen (OR 1.013; 95% CI 1.0031.023) were determined as predictors of IC. (FET: Fischer's Exact Test, OR: Odds ratio, CI: Confidence intervals). Conclusions: This study suggests that hypercoagulability, hereditary or acquired, plays an essential role in the manifestation of IC.

The role of hypercoagulability in ischemic colitis

Objective. The aim of this study is to evaluate the role of thrombophilia-hypercoagulability in ischemic colitis (IC). Material and methods. Thrombophilia and fibrinogen were evaluated in 56 cases of IC and 44 controls with known predisposing factors but no evidence of IC. Thrombophilic factors tested were: protein C (PC), protein S, antithrombin (AT), resistance to activated protein C (APCR), lupus anticoagulant (LA), factor V G1691A mutation (FV Leiden), prothrombin G20210A mutation, methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C mutations and plasminogen activator inhibitor-1 (PAI-1) gene 5G/4G and 4G/4G polymorphisms. Results. In IC group were recorded: i) low levels of PC and AT (p = 0.064 and p = 0.022, respectively); ii) low levels of APCR (normal: >2, p = 0.008); iii) high levels of fibrinogen (p = 0.0005); iv) higher number of homozygotes for MTHFR A1298C and C677T mutations (p = 0.061 and p = 0.525 (Pearson chi-square), respectively); v) greater prevalence of 5G/4G and 4G/4G polymorphisms (p = 0.031 (Pearson chi-square)) and vi) higher incidence of LA-positive individuals (p = 0.037, Fischer’s exact test). Multivariate analysis was performed to determine the effects of prothrombotic factors in IC. 5G/4G polymorphism of PAI-1 gene (odds ratio (OR) 12.29; 95% confidence interval (CI) 2.26–67.00), APCR (OR 0.089; 95% CI 0.011–0.699) and fibrinogen (OR 1.013; 95% CI 1.003–1.023) were determined as predictors of IC. Conclusions. This study suggests that hypercoagulability, hereditary or acquired, plays an essential role in the manifestation of IC.

Risk factors of recurrent ischemic colitis: a multicenter retrospective study.

Recurrence of ischemic colitis (IC) has not been studied extensively. The aim of this study was to investigate the characteristics of recurrent IC in the community setting and to identify any risk factors. We conducted a retrospective study in two community hospitals. Medical records of patients with IC from January 2007 to January 2013 were reviewed. Demographic details, clinical features, co- morbidities, concomitant use of medications,laboratory studies, imaging findings, endoscopic and histological features, surgery, hospital stay, and death within 30 days were collected. Patients were divided into two groups (recurrent IC group, non-recurrent IC group). A total of 118 patients with IC were identified. IC recurred in 10 patients (8.5%) during the study period. Half of the patients in the recurrent IC group were current smokers as compared to only 18.7% of patients in the non-recurrent group. In the recurrent IC group, 20.0% of patients never smoked as compared to 61.7% in the non-recurrent group (p=0.027).Abdominal aortic aneurysm (AAA) was more frequent in the recurrent IC group (40.0% vs. 4.7%; p=0.003). No differences in other clinical symptoms, CT scan findings, comorbidities, endoscopic features, or use of concomitant medications were observed between the two groups. The need for surgical intervention, blood transfusion, intensive care unit stay, mechanical ventilation,length of hospital stay, and anatomic location of affected segments did not differ between the two groups. IC recurred in 8.5% of patients during the six-year study period. Current smoking status and presence of AAA were identifying risk factors for recurrence of IC.

Clinical characteristics of ischemic colitis and ulcerative colitis

Objective To compare the clinical characteristics of ischemic colitis （IC） and ulcerative colitis （UC）. Methods The data of 43 IC patients and 36 UC patients diagnosed from January 2008 to June 2011 were compared on the clinical and endoscopic characteristics. Results There were statistical differences in terms of gender, age, course of disease and underlying diseases between the two groups （P 〈 0. 05）. IC was more frequently seen in aged women with cardiovascular diseases, and with short course of disease （29/43,67.0%）. IC group showed higher CRP and lower PLT levd than did UC group（ P 〈0.05 ）. IC mostly involved sigmoid colon,with localized lesions of vertical or irregular ulcer which cured more quick and characterized with mucosal inflammation, while UC mainly originated from rectum and involved the whole intestinal wall, manifested with scattered spot ulcer, cryptitis and abscess. Conclusion Age, disease course, underlying diseases, serum CRP level, endoscopic and pathological characteristics are all factors to consider for differential diagnosis of IC and UC. Key words: Isehemic colitis; Colitis,ulcerative; Diagnosis

Exploration on value of combination detection of CRP and VEGF in the diagnosis of ischemic colitis

Objective To explore the clinical value of CRP and VEGF in the diagnosis of ischemic colitis.Method The serum of CRP and VEGF in 59 patients with ischemic colitis and 30 healthy volunteers were tested and compared.Then the testing results of two groups were analyzed.Results CRP and VEGF levels of ischemic colitis patients group were significantly higher than those of the healthy group (P＜0.05); CRP and VEGF levels of ischemic colitis patients group were compared with the narrow type of ischemic colitis group,the result was statistically significant (P＜0.05).Conclusion Combination of CRP and VEGF contributes to classification and differential diagnosis in ischemic colitis. Key words: CRP; VEGF; Ischemic colitis

Paraoxonase and Arylesterase Activities, Lipid Profile, and Oxidative Damage in Experimental Ischemic Colitis Model

Objective. In the present study, since PON1 is known as an HDL-associated antioxidant enzyme that inhibits the oxidative modification of LDL and oxidative stress plays a role in the pathogenesis of mesenteric ischemia, we investigated the changes in PON1 activity and lipid profile in an experimental ischemic colitis model. Methods. Forty male Wistar albino rats were divided into two groups: the control group (N = 15) and the experimental group (N = 25). All animals were anesthetized with ether and ketamine anesthesia to undergo a midline laparotomy. Ischemic colitis was induced by marginal vessel ligation in the splenic flexura (devascularization process). A sham laparotomy was performed in the control group. All animals were sacrificed on the seventh postoperative day. Oxidative stress marker (malonyldialdehyde, MDA), lipid profile, and paraoxonase (PON-1) and arylesterase activities were determined. Histopathological evaluation was done under light microscopy, after sectioning and staining with hematoxyline and eosin. Statistical analysis was conducted using Student's t-test and Mann-Whitney U test, and P < 0.05 was considered as statistically significant. Results. There was a significant decrease in both serum and tissue PON1 activity in ischemic colitis group (P < 0.01, for each). Similarly, arylesterase levels showed a parallel decrease in both tissue and serum of the experimental group (P < 0.01 and P < 0.001, retrospectively). MDA, an oxidative stress marker, was seen to increase in the experimental group (P < 0.01, tissue; P < 0.05, serum). In experimental group, there was a significant rise in serum total cholesterol and LDL levels (P < 0.001, for each). However, HDL level decreased significantly (P < 0.001). Triglycerides did not show any change between the groups (P > 0.05). Conclusions. PON1 and arylesterase play an important role in the pathophysiology of ischemic colitis.

The Effect of Erythropoietin on Ischemic Colitis: An Experimental Rodent Model: Original Article

Background: Erythropoietin (Epo), a hormone produced by the kidney that promotes the formation of red blood cells in the bone marrow, is considered anti-inflammatory,anti-apoptotic, angiogenetic and sitoprotective. In this study, high dose erythropoietin is examined on an animal model for ischemic colitis (IC) to detect its possible potential benefits. Methods: Thirty female Wistar albino rats weighing 250-300 g were randomized into three experimental groups as follows: in Group 1, animals were sham operated (n = 10) and received distilled water; in Groups 2 and 3, the rats underwent a standardized surgical procedure to induce IC (n = 10 in each group). Group 2 animals served as the controls, receiving only tap water, while Group 3 animals received 3000 IU/kg eritropoetin as a single high dose. All animals were sacrificed 72 h after devascularization. Colonic malondialdehyde (MDA) levels, glutathione (GSH), myeloperoxidase (MPO), and caspase 3 activities of the sacrified rats were measured. CD-34 was evaluated by the immunohistochemical examination of the colonic tissue. Results: Colonic ischemia significantly increased the colonic MDA levels, caspase 3 activity, and TNF alfa in comparison to the control group. Epo treatment was associated with increased GSH levels, decreased MDA, and caspase 3 activity. Histopathological examination revealed that the intestinal mucosal structure was preserved in the Epo treated group. Moreover, treatment with Epo significantly increased CD-34 (stem cell) when compared to the ischemic colitis group. Conclusion: Epo reduced colonic damage in ischemic colitis. The mechanism of the protection associated with Epo was due to its mobilization of the stem cells as well as its anti-apoptotic and anti-inflammatory effects.

Can We Predict the Development of Ischemic Colitis Among Patients with Lower Abdominal Pain?

This study was performed to find clinical risk factors for developing ischemic colitis in patients experiencing lower abdominal discomfort with or without bloody diarrhea. A total of 467 patients who underwent sigmoidoscopy or colonoscopy because of lower abdominal discomforts with or without blood in stool were consecutively enrolled; 147 patients were diagnosed endoscopically and histologically as having ischemic colitis. The control group was composed of the remaining 320 patients with nonspecific endoscopic/histologic findings. Clinical variables were compared between the ischemic colitis group and the control group. After excluding 67 patients in the ischemic colitis group, we compared the remaining 80 patients to the control group, using various clinical parameters. According to the logistic regression analysis, six factors were significantly related to ischemic colitis: older than aged 60 years (adjusted odds ratio, 5.7; 95 percent confidence interval: 2.6-11.7), hemodialysis (5; 1.2-21.6), hypertension (4.9; 2.3-10.5), hypoalbuminemia (3.5; 1.8-6.7), diabetes mellitus (3.4; 1.3-8.8), and constipation-inducing medications (2.8; 1.1-7.1). Through our analysis, we were able to predict the development of ischemic colitis for the patients with 0, 1, 2, 3, or 4+ risk factors: 8, 21, 55, 79, and 100 percent, respectively. Old age, hemodialysis, hypertension, diabetes mellitus, hypoalbuminemia, and constipation-inducing medications are clinically important risk factors for ischemic colitis in patients experiencing lower abdominal discomfort with or without bloody stool. By considering these factors, we were able to predict with high accuracy the development of ischemic colitis.

Factors predicting poor prognosis in ischemic colitis.

To determine the clinical, analytical and endoscopic factors related to ischemic colitis (IC) severity. A total of 85 patients were enrolled in a retrospective study from January 1996 to May 2004. There were 53 females and 32 males (age 74.6+/-9.4 years, range 45-89 years). The patients were diagnosed as IC. The following variables were analyzed including age, sex, period of time from the appearance of symptoms to admission, medical history, medication, stool frequency, clinical symptoms and signs, blood tests (hemogram and basic biochemical profile), and endoscopic findings. Patients were divided in mild IC group and severe IC group (surgery and/or death). Qualitative variables were analyzed using chi-square test and parametric data were analyzed using Student's t test (P<0.05). The mild IC group was consisted of 69 patients (42 females and 27 males, average age 74.7+/-12.4 years). The severe IC group was composed of 16 patients (11 females and 5 males, average age of 73.8+/-12.4 years). One patient died because of failure of medical treatment (no surgery), 15 patients underwent surgery (6 after endoscopic diagnosis and 9 after peroperatory diagnosis). Eight of 85 patients (9.6%) died and the others were followed up as out-patients for 9.6+/-3.5 mo. Demographic data, medical history, medication and stool frequency were similar in both groups (P>0.05). Seriously ill patients had less hematochezia than slightly ill patients (37.5% vs 86.9%, P = 0.000). More tachycardia (45.4% vs 10.1%, P = 0.011) and a higher prevalence of peritonism signs (75% vs 5.7%, P = 0.000) were observed in the severe IC group while the presence and intensity of abdominal pain were similar between two groups. Two patients with severe IC had shock when admitted. Regarding analytical data, more seriously ill patients were found to have anemia and hyponatremia than the mildly ill patients (37.5% vs 10.1%, P = 0.014 and 46.6% vs 14.9%, P = 0.012, respectively). Stenosis was the only endoscopic finding that appeared more frequently in seriously ill patients than in slightly ill patients (66.6% vs 17.3%, P = 0.017). The factors that can predict poor prognosis of IC are the absence of hematochezia, tachycardia and peritonism, anemia and hyponatremia and stenosis.

The colon single-stripe sign and its relationship to ischemic colitis

Objectives Endoscopic findings may assist in the clinical diagnosis of ischemic colitis but have not been systematically characterized. We noted that a single linear colonic ulcer could on occasion be found endoscopically after hypotension and proceeded to investigate its relationship to ischemic colitis. Methods Twenty-six patients (19 female and seven male, mean age 71 yr) with endoscopic evidence of a single linear ulcer running along the longitudinal axis of the colon (colon single-stripe sign (CSSS) were retrospectively studied. Colitis etiologies were determined in the CSSS patients and in 58 consecutive patients without a stripe forming a colitis comparison group; clinical course and outcome in CSSS patients subsequently were compared with those in 22 patients with circumferentially involved ischemic colitis. Results The CSSS was ≥5 cm in length in all instances and isolated to a segment of the left colon in 89%. Evidence of a preceding ischemic event was noted significantly more often in the CSSS (62%) patients than in the colitis comparison group (7%) ( p < 0.0001). On blinded histopathological examination, 75% of CSSS cases had microscopic evidence of ischemic injury compared with 13% in the colitis comparison group ( p < 0.0001). None of the CSSS patients required surgical intervention, whereas six (27%) patients from the circumferential ischemic colitis group underwent exploration ( p < 0.05). Nine patients (41%) in the circumferential ischemic colitis group died, whereas there was one death in the CSSS group (4%) ( p < 0.05). Conclusions Ischemia can manifest endoscopically as the CSSS. This sign seems to characterize milder disease in the clinical spectrum of ischemic colitis.

Spontaneous and shock-associated ischemic colitis

Ischemic changes in the colon that progress to gangrene present diagnostic and therapeutic difficulties associated with poor survival. During the past 10 years, 36 patients with colonic ischemia were treated. Two clinical groups were evident. The spontaneous ischemic colitis group (type I) included 17 patients who were well before the onset of gastrointestinal symptoms. The cause of type I ischemic colitis is not apparent; it is attributed to occlusive or nonocclusive ischemia. The other group (type II) included 19 patients who developed ischemia of the colon associated with shock secondary to various disease processes. Radiographic evidence of distended bowel correlated well with full-thickness necrosis as determined clinically or pathologically. Twenty-one patients died, for a mortality rate of 58 percent. While full-thickness gangrene was fatal in 71 percent of the patients, mucosal necrosis only was associated with an 88 percent survival rate. The results of treatment should improve with an increased awareness of ischemic colitis, earlier appropriate operative intervention, and more appropriate use of ileostomy and colostomy.