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PubMed1997

Extracellular matrix composition and gene expression in collagenous colitis.

BACKGROUND & AIMS: Collagenous colitis is a rare diarrheal disease of unknown pathophysiology that is histologically defined by subepithelial bandlike structures. The objective of this study was to elucidate the biochemical composition and the origin of the bandlike structures in collagenous colitis. METHODS: Immunohistochemical and in situ hybridization analyses were performed on endoscopic specimens using specific antibodies and riboprobes for collagen types I, III, IV, and VI and for the glycoprotein tenascin. RESULTS: In collagenous colitis, the mucosal matrix with the exception of the bands retained a normal architecture and extracellular matrix composition. The bands stained most prominently for type VI collagen and tenascin. Less abundant staining for both proteins was also found in the subepithelial matrix of the normal mucosa. In situ hybridization showed no significant increase in collagen type VI messenger RNA expression in cells around and entrapped in the bands in collagenous colitis compared with normal specimens. CONCLUSIONS: The results support the suggestion that collagenous colitis is a localized alteration of the extracellular matrix, which involves the pericryptal-subepithelial myofibroblast sheath. The data suggest that reduced matrix degradation and not overactivation of matrix synthesis may be the reason for the subepithelial accumulation of matrix proteins.

Adult↗
PubMed1998

Efficacy of open-label bismuth subsalicylate for the treatment of microscopic colitis.

BACKGROUND & AIMS: The pathogenesis of the microscopic colitis syndrome is unknown but may involve bacteria, an intestinal luminal antigen, and/or autoimmunity. It was hypothesized that bismuth subsalicylate would resolve both diarrhea and colonic inflammation in microscopic colitis because it possesses antidiarrheal, antibacterial, and anti-inflammatory properties. METHODS: Thirteen patients with microscopic colitis (7 with subepithelial collagen deposition and 6 without) were treated with eight chewable 262-mg bismuth subsalicylate tablets per day for 8 weeks. Patients recorded the frequency of bowel movements daily. Forty-eight-hour stool collections and flexible sigmoidoscopy with 24 biopsies were performed before and after treatment in each patient. RESULTS: Twelve patients completed the trial. Eleven patients had a resolution of diarrhea and a reduction in fecal weight. The average time to respond was 2 weeks. In 9 patients, colitis resolved. When present before treatment, subepithelial collagen thickening disappeared. Those completing the trial experienced no side effects. Posttreatment follow-up for 7-28 months shows that 9 patients remain well having undergone no further treatment, 2 are well but required retreatment, and 1 has continued diarrhea. CONCLUSIONS: Bismuth subsalicylate treatment for 8 weeks is safe and well tolerated. This regimen appears to be efficacious for the treatment of microscopic colitis and is worthy of further study in a controlled trial.

Administration, Oral↗
PubMed1999

Varying cecal bacterial loads influences colitis and gastritis in HLA-B27 transgenic rats.

BACKGROUND & AIMS: Recent data support an important role of resident luminal bacteria in experimental colitis. We determined how altered cecal bacterial loads influence colitis and gastritis. METHODS: A cecal self-filling blind loop (SFBL) was created or the cecum was excluded from the fecal stream in specific pathogen-free HLA-B27 transgenic (TG) rats with early colitis and in nontransgenic (nonTG) littermates; controls underwent sham operation (SHAM). Luminal bacterial concentrations were determined by culture and counting chamber. RESULTS: TG rats with SFBL had more severe cecal inflammation and leukocytosis than TG SHAM controls. TG excluded rats with low cecal bacterial loads had no cecal inflammation and less colitis and gastritis than SHAM controls, despite having normal distal colonic and gastric bacterial concentrations. Metronidazole attenuated cecal inflammation and eliminated Bacteroides in SFBL TG rats. NonTG SFBL rats had mild cecal inflammation and no gastritis and colitis. The ratio of total anaerobic to aerobic bacteria was 1000-fold greater in SFBL than in SHAM rats, with a 10,000-fold increased ratio of Bacteroides spp. to aerobes. CONCLUSIONS: The luminal bacterial load and composition determines the activity of cecal inflammation in genetically susceptible hosts. Lowering cecal bacterial concentrations can diminish inflammation in remote organs.

Animals↗
PubMed1999

Cigarette smoke aggravates experimental colitis in rats.

BACKGROUND & AIMS: Tobacco smoking has a complex effect on intestinal inflammation, being protective in ulcerative colitis, whereas it aggravates Crohn's disease. The beneficial effect of smoking has been attributed to nicotine, but the mechanisms underlying the adverse effect are still under investigation. The aim of this study was to examine the effect of cigarette smoking on experimental colitis in rats and to investigate the underlying mechanism. METHODS: Rats were exposed daily to cigarette smoke by means of a specialized smoking chamber. Control rats were placed in the same chamber without introducing smoke. In parallel experiments, rats received the ganglionic blocker hexamethonium before smoke exposure. After 2 weeks, colitis was induced by dinitrobenzenesulfonic acid (DNBS), and inflammation was assessed 3 days later. RESULTS: Exposure to cigarette smoke significantly increased macroscopic and histological damages as well as myeloperoxidase activity compared with sham-treated controls. Treatment with hexamethonium before smoking reversed the effect of the smoke on the colitis, improving all parameters. CONCLUSIONS: Exposure to cigarette smoke aggravates DNBS-induced colitis in the rat. This effect is reversed by hexamethonium, suggesting that a neural pathway is involved.

Animals↗
PubMed2000

How gastroenterologists screen for colonic cancer in ulcerative colitis: an analysis of performance.

BACKGROUND: The aim of this study was to assess the colorectal cancer surveillance practices of British gastroenterologists for patients with ulcerative colitis. METHODS: A questionnaire that investigated aspects of surveillance in patients with ulcerative colitis was mailed to all consultant gastroenterologists in the U.K. (n = 413). RESULTS: Three hundred forty-one questionnaires were returned (response rate 83%). Ninety-four percent of consultants practice cancer surveillance in ulcerative colitis, with 35% maintaining a registry of patients in surveillance programs. All gastroenterologists perform surveillance in patients with pancolitis, 24% in those with left-sided colitis and 2% in patients with proctitis. The mean duration of disease before surveillance is commenced is 9.2 years for pancolitis and 12.4 years for left-sided colitis (p < 0.0001). Only 4% of gastroenterologists routinely offer patients with disease of more than 10 years' duration a prophylactic colectomy. Colonoscopies are conducted by an accredited gastroenterologist in 65% of cases and biopsies are reviewed by specialists in gastrointestinal pathology in 45%. When histology reveals low-grade dysplasia only 4% advise colectomy and when high-grade dysplasia is found 53% recommend colectomy. Sixteen percent of gastroenterologists were unaware of the significance of a dysplasia associated lesion or mass. CONCLUSION: The majority of gastroenterologists practice surveillance on a disorganized basis. There is inconsistency in the management of patients with dysplasia and education of gastroenterologists is needed.

Biopsy↗
PubMed1995

Patchiness of mucosal inflammation in treated ulcerative colitis: a prospective study.

Conventional wisdom dictates that ulcerative colitis affects contiguous areas of the colon and is most severe in the rectum, and that the finding of rectal sparing or patchy involvement should raise suspicions of Crohn's disease. We and others have noted occasional rectal sparing and patchy involvement in patients with ulcerative colitis. Therefore, we prospectively studied the prevalence of patchiness, including rectal sparing, in treated cases of ulcerative colitis. Consecutive patients with longstanding ulcerative colitis were studied. The left colon was divided into three zones for scoring degree of activity, and biopsy specimens from each zone were graded for histologic activity by a blinded observer. Patchiness by endoscopy or histology was defined as (1) frank rectal sparing (normal appearance endoscopically; absence of inflammation of the lamina propria and crypts histologically); (2) areas of greater inflammation proximally than distally; or (3) discrete areas of patchiness endoscopically within any one zone. Of 39 patients evaluated, 17 (44%) had endoscopic evidence of patchiness, including 5 (13%) with rectal sparing. Thirteen (33%) had histologic evidence of patchiness, including 6 (15%) with rectal sparing. Both endoscopic and histologic patchiness were seen in 9 patients (23%). The patchy and nonpatchy groups did not differ in regard to the use of rectal therapy. In patients with treated ulcerative colitis, the finding of rectal sparing or patchiness should not necessarily indicate a change in the diagnosis to Crohn's disease.

Adult↗
PubMed1998

Technetium Tc 99m hexamethyl propylene amine oxine leukocyte scintigraphy in patients with ulcerative colitis: correlation with clinical, biologic, endoscopic, and pathologic intensity, and local release of interleukin 8.

BACKGROUND: Technetium Tc 99m hexamethyl propylene amine oxine (99mTc-HMPAO) has been used to radiolabel leukocytes with promising results for its clinical use in inflammatory bowel disease. During active ulcerative colitis, colonoscopy is indicated to determine the extent and the intensity of the disease for proper management. The aim of this prospective study was to determine whether 99mTc-HMPAO-labeled leukocyte scintigraphy can give information similar to that obtained with colonoscopy during acute attacks of ulcerative colitis. METHODS: Thirty-three consecutive patients with 50 acute episodes of ulcerative colitis underwent 99mTc-HMPAO scintigraphy and colonoscopy with biopsies. Scintigraphic determination of disease extent and intensity were compared with those obtained by colonoscopy with biopsies and clinicobiologic markers. RESULTS: The scintigraphic index of disease intensity was correlated with endoscopic index, Truelove index, biologic markers, and local release of interleukin-8. The extent measured by scintigraphy was well correlated to the endoscopic and histologic extent. CONCLUSIONS: 99mTc-HMPAO scintigraphy accurately determines the extent and the intensity of acute ulcerative colitis lesions. This noninvasive method can specify the extent and the intensity of an acute attack in patients with previously known ulcerative colitis.

Adult↗
PubMed1996

Use of air enema radiography to assess depth of ulceration during acute attacks of ulcerative colitis.

BACKGROUND Acute colitis is usually assessed by means of plain abdominal radiographs, the diagnostic utility of which can be enhanced by barium enema. Colonoscopy can also be useful. The latter methods may be laborious and carry risk. We describe a radiographic technique using air as the contrast medium to show mucosal or deeper ulceration. METHODS Of 60 patients undergoing colectomy for acute ulcerative colitis, 35 had air enema radiography and 14 had plain films with sufficient amount of spontaneously occurring gas to allow visualisation of the mucosa, during the 10 days before surgery. The degree of inflammation on air enema films and the extent of histopathological ulceration in colectomy specimens were independently graded and compared with each other. Depth of ulceration was compared with clinical data including a preoperative risk stratification, the APACHE II score. FINDINGS The degree of inflammation on air enema radiography correlated significantly with depth of ulceration at histopathological examination (rs 0.61, p<0.001). Presence of mucosal changes had a close association with deep ulceration extending into the muscularis propria layer or beyond (p<0.001). Air enema radiography had a high sensitivity (0.91) for presence of and specificity (0.75) in the exclusion of deep ulceration, with positive and negative predictive values of 0.88 and 0.80. 42 of 49 patients were correctly classified as regards deep ulcers. The correlation between higher preoperative APACHE II scores and severity of histopathological colitis was weak (rs 0.30, p<0.05). INTERPRETATION Air enema radiography reliably assesses the presence of colonic ulceration in patients with an acute attack of ulcerative colitis. It is a first-line investigation to assess the presence of deeper ulceration in acute colitis.

APACHE↗
PubMed2002

High resolution analysis of chromosome 18 alterations in ulcerative colitis-related colorectal cancer.

We previously have demonstrated by comparative genomic hybridization that 80% of ulcerative colitis-related cancers show loss of all or part of chromosome 18, the site of at least three candidate tumor suppressor genes: DCC, SMAD2, and SMAD4. To determine whether these genes are targeted in colitis-related carcinogenesis, we performed a high-resolution analysis of chromosome 18 alteractions in 32 colitis-related colorectal cancers by assessing allelic imbalance at 11 microsatellite markers distributed along the chromosome, and by the quantitative polymerase chain reaction (PCR) method (TaqMan). TaqMan analysis was used to determine the relative copy number of five test genes on chromosome 18 (PACAP on 18p and DCC, SMAD2, SMAD4, and GALNR on 18q). We found allelic imbalance, as assessed by loss of heterozygosity, in at least one marker on chromosome 18 in 25 of the 29 tumors (86%) successfully tested. In 14 tumors, allelic imbalance was detected at all informative markers on 18q, while the other 11 tumors showed only partial loss. Allelic imbalance was most commonly detected at D18S363 (78% of informative cases). This marker is in closest proximity to SMAD4. By quantitative PCR analysis, a relative loss of copy number of SMAD2, SMAD4, and DCC were detected in 40%, 57%, and 53%, respectively, of the colitis-related cancers. SMAD2 was retained in four tumors having loss of SMAD4 and DCC. Loss of SMAD4 alone was seen in one tumor. The present data indicate that the loss of SMAD4 and DCC occurs in the majority of colitis-related cancers.

Adult↗
PubMed2003

Pronounced chromosomal instability and multiple gene amplifications characterize ulcerative colitis-associated colorectal carcinomas.

Patients with ulcerative colitis have a significantly increased lifetime risk for the development of colorectal carcinomas. While genetic and genomic changes during carcinogenesis have been thoroughly studied in sporadic colorectal cancers, less is known about ulcerative colitis-associated colorectal carcinomas. The aim of this study was to extend the identification of specific genomic imbalances to ulcerative colitis-associated colorectal carcinomas and to establish a comprehensive map of DNA gains and losses by investigating 23 tumor specimens from 23 patients. The molecular cytogenetic characterization was performed using comparative genomic hybridization; immunohistochemistry was used to measure proliferative activity and laminin-5 expression as a marker for invasiveness. The results indicate that these tumors are invariably aneuploid, with a high proliferative activity and increased invasive potential. The average number of copy alterations correlates with increased cyclin A levels (P=0.044), which is an independent predictor of risk of carcinoma development in ulcerative colitis. Despite severe genetic instability, the general pattern of specific chromosomal aberrations that defines sporadic colorectal carcinomas is maintained in ulcerative colitis-associated malignancies. High-level copy number increases (amplifications) are dispersed throughout the genome. Strikingly, these amplifications are much more frequent than in sporadic carcinomas and map to chromosomal regions that have not been described before.

Adenocarcinoma↗
PubMed2003

Anti-inflammatory effects of leptin and cholecystokinin on acetic acid-induced colitis in rats: role of capsaicin-sensitive vagal afferent fibers.

Leptin and cholecystokinin (CCK) have a synergistic interaction in the suppression of food intake, and afford similar gastroprotective activity. The present study was designed to investigate the putative protective effects of CCK and leptin on acute colonic inflammation. Leptin or CCK-8s was injected to rats intraperitoneally immediately before and 6 h after the induction of colitis with acetic acid. CCK-A receptor antagonist (L-364,718) or CCK-B receptor antagonist (L-365,260) was injected intraperitoneally 15 min before leptin or CCK treatments. In a group of rats, vagal afferent fibers were denervated by topical application of capsaicin on the cervical vagi. Rats were decapitated at 24 h, and the distal 8 cm of the colon were removed for macroscopic scoring, determination of tissue wet weight index (WWI), histologic assessment and tissue myeloperoxidase (MPO) activity. All inflammation parameters were increased by acetic acid-induced colitis compared to control group. Leptin or CCK-8s treatment reduced these parameters in a similar manner, while co-administration of leptin and CCK was found to be more effective in reducing the macroscopic score and WWI. CCK-8s-induced reduction in the score and WWI was prevented by CCK-A, but not by CCK-B receptor antagonist, whereas neither antagonist altered the inhibitory effect of leptin on colitis-induced injury. On the other hand, perivagal capsaicin prevented the protective effects of both CCK-8s and leptin on colitis. Our results indicate that leptin and CCK have anti-inflammatory effects on acetic acid-induced colitis in rats, which appear to be mediated by capsaicin-sensitive vagal afferent fibers involving the reduction in colonic neutrophil infiltration.

Acetic Acid↗
PubMed1998

Lack of beneficial effect of a tachykinin receptor antagonist in experimental colitis.

Nerves within the wall of the intestine may contribute to inflammatory responses, such as those occurring in inflammatory bowel disease. Studies in an experimental model of colitis have demonstrated that neuromodulation, through chemical sympathectomy or administration of lidocaine, can markedly attenuate granulocyte infiltration and tissue injury. Given the many pro-inflammatory effects of substance P, we have evaluated the effects of a tachykinin receptor (NK-1) antagonist, RP 67580, in models of acute colitis in the rat and guinea pig. While administration of RP 67580 and a second NK-1 antagonist (CP-96,345-1) significantly reduced the infiltration of granulocytes into colonic tissue during the first 12 h after induction of colitis in the rat, repeated administration of RP 67580 over a three day period failed to significantly affect granulocyte recruitment or the severity of tissue injury. In contrast, lidocaine enemas were effective in reducing both indices of inflammation/injury. In the guinea pig, similar observations were made. These observations demonstrate that blockade of NK-1 receptors over a three day period failed to significantly modify the course of experimental colitis. It remains possible that the beneficial effects of lidocaine may be due, in part, to inhibition of substance P release, and that the contribution of substance P to inflammation in experimental colitis occurs through NK-1 receptor-independent mechanisms.

Analgesics↗
PubMed2002

Chitosan capsules for colon-specific drug delivery: enhanced localization of 5-aminosalicylic acid in the large intestine accelerates healing of TNBS-induced colitis in rats.

The objective of this study was to achieve the colon-specific delivery of an anti-ulcerative colitis drug using chitosan capsules and to accelerate healing of 2,4,6-trinitrobenzene sulfonic acid sodium salt (TNBS)-induced colitis in rats. 5-Aminosalicylic acid (5-ASA) was used as a model of an anti-inflammatory drug. The gastrointestinal transit of chitosan capsules was determined by counting the number of capsules in the gastrointestinal lumen by celiotomy at certain times after their oral administration to rats. The chitosan capsules reached the large intestine 3.5 h after oral administration in rats. We studied the release of 5-ASA from chitosan capsule by the Japan Pharmacopoeia (JP) rotating basket method. The release of 5-ASA from the chitosan capsule markedly increased in the presence of rat cecal contents. After oral administration of chitosan capsules containing 5-ASA, the concentrations of 5-ASA in the large intestinal mucosa were higher than those in the CMC suspension. For the treatment of colitis in rats, 5-ASA was orally administered using chitosan capsules or a carboxy methyl cellulose (CMC) suspension to TNBS-induced rats. The colonic injury and inflammation were assessed by measuring the myeloperoxidase (MPO) activities, colon wet weight/body weight (C/B) ratio and the damage score, respectively. When 5-ASA was orally administered using chitosan capsules in TNBS-induced colitis rats, we found better therapeutic effects with 5-ASA than with a 5-ASA CMC suspension, as evaluated by the MPO activities, C/B ratio and the damage score. In conclusion, chitosan capsules may be useful carriers for the colon-specific delivery of anti-inflammatory drugs including 5-ASA and the healing of TNBS-induced colitis in rats.

Administration, Oral↗
PubMed1999

Vagally dependent protective action of calcitonin gene-related peptide on colitis.

This work evaluates the mechanism of action of calcitonin gene-related peptide (CGRP) on colitis. Firstly, Wistar rats were intracolonically instilled with trinitrobenzenesulfonic acid (TNBS) and i.v. treated by either alphaCGRP, or hCGRP(8-37), or by vehicle. The inflammatory level was evaluated 8 h and 4 days after TNBS. Secondly, intracerebroventricular alphaCGRP was assessed on the 4-day group with colitis. Finally, i.v. alphaCGRP was administered in vagotomized animals, and tested on the 4-day group with colitis. Colitis was aggravated by hCGRP(8-37), and decreased by peripheral but not central alphaCGRP. AlphaCGRP was inactive on inflammatory parameters in vagotomized colitic rats. This suggests that endogenous peripheral CGRP has an anti-inflammatory role in TNBS-induced colitis, depending upon the integrity of the vagus.

Animals↗
PubMed2003

Clinical and genetic heterogeneity in Mexican patients with ulcerative colitis.

Ulcerative colitis (UC) is an inflammatory bowel disease of unknown etiology. Genetic factors implied on its onset and severity may include genes located within the class II major histocompatibility complex (MHC) region. The aim of this study was to determine the relationship between human leukocyte antigen (HLA)-DRB1 alleles with the clinical disease patterns of UC in Mexican Mestizo patients. High-resolution HLA typing was performed by polymerase chain reaction-sequence specific oligonucleotide (PCR)-SSO reverse dot blot and PCR-single-strand polymorphism in 67 patients with UC and 99 ethnically matched healthy controls. UC patients overall showed an increased frequency of HLA-DR1 as compared with healthy controls (17.1% versus 5%, [pC = 0.003, OR = 3.9]). Patients with extensive colitis showed increased frequencies of HLA-DR1 (pC = 1 x 10(-10), OR = 13.9), HLA-DRB1*0103 (pC = 1 x 10(-3), OR = 21.7), HLA-DRB1*0102 (pC = 0.007, OR = undetermined), and HLA-DR15 (pC = 1 x 10(-3), OR = 8.5) when compared with healthy controls. We also found a statistically increased frequency of HLA-DR15 in UC patients with extensive colitis compared with UC patients with only distal colitis (18.7% versus 1.8%, pC = 0.03; OR = 12.2). When patients who underwent proctocolectomy were compared with those who did not, an increased frequency of HLA-DRB1*0103 was observed (21.8% versus 4.9%; pC = 0.03; OR = 5.4; 95% confidence interval, 1.39-21.93). Also, patients with proctocolectomy showed increased frequencies of HLA-DR1 (pC = 1 x 10(-3), OR = 24.2) and HLA-DRB1*0103 (pC = 1 x 10(-3), OR = 50.6) when compared with healthy controls. We concluded that HLA-DR1 is associated with genetic susceptibility to UC in the Mexican Mestizo population. HLA-DR15 distinguishes a subgroup of patients with extensive colitis and the HLA-DRB1*0103 allele distinguishes a subgroup of severe form of disease that might require surgical management.

Adult↗
PubMed1999

[Lymphocytic colitis and Gougerot-Sjögren syndrome. Report of two cases].

INTRODUCTION: Microscopic colitis describes a subset of patients with chronic watery diarrhea of unknown origin, and normal endoscopic findings and microscopic evidence of an inflammatory infiltrate in the colonic mucosa. We report two cases associated with sicca syndrome. EXEGESIS: A 56-year-old woman and a 76-year-old man presented with a history of lymphocytic colitis associated with sicca syndrome. Drugs or infectious agents were not implicated in the cause of lymphocytic colitis, suggesting that sicca syndrome may be involved in the pathogenesis of microscopic colitis. CONCLUSION: These cases suggest that sicca syndrome should be detected in patients with lymphocytic colitis.

Aged↗
PubMed2002

Protective effects of Polygalae root in experimental TNBS-induced colitis in mice.

In this study, the protective effect of Polygalae root was evaluated in a murine model of experimental colitis by intrarectal injection with 2,4,6-trinitrobenzene sulfonic acid (TNBS). Polygalae root, given orally at 2, 4 g/kg body weight of herbs once a day consecutively for 9 days, could recover the lost body weight and decrease the gross rectal bleeding. Polygalae root also reduced the degree of inflammation and improved significantly the histological changes such as infiltration by polymorphonuclear leukocytes and multiple erosive lesions. Furthermore, the cytokine production of intraepithelial lymphocytes was analyzed. The results showed that IFN-gamma was increased, but IL-4 was decreased in TNBS-induced colitis, when those were compared with the sham controls. But the administration of Polygalae root to TNBS-induced colitis mice showed lower production of IFN-gamma and higher production of IL-4 than the TNBS-induced colitis. These results suggest that the protective effects of Polygalae root against the TNBS colitis may be associated with the regulation of cytokine production of intraepithelial lymphocytes.

Animals↗
PubMed1996

Pelvic radiation therapy as a risk factor for ischemic colitis complicating abdominal aortic reconstruction.

Ischemic colitis is an infrequent but potentially devastating complication of abdominal aortic reconstruction. Identification of patients with predisposing risk factors for the development of ischemic colitis can guide intraoperative measures to preserve or restore colonic blood flow during aortic surgery. Previous radiation therapy for pelvic malignancy may be one such predisposing risk factor. Two cases are presented in which ischemic colitis complicated abdominal aortic reconstruction in the setting of previous pelvic irradiation. In the months after radiation therapy for prostate cancer, one patient underwent infrarenal abdominal aortic aneurysm repair. Ischemic infarction of the sigmoid colon developed acutely after surgery and required emergent sigmoid colectomy. The second patient underwent reconstruction of an infrarenal abdominal aortic aneurysm after having had radiation therapy for a bladder tumor. Despite an initial satisfactory result, the patient's abdominal pain and diarrhea progressively worsened and he eventually required sigmoid colectomy for severe ischemic colitis. In both of these patients, the inferior mesenteric arteries were patent and had not been reimplanted. The association of pelvic radiation therapy with ischemic colitis after aortic reconstruction should focus attention to the operative details for maintaining the colonic circulation in these patients. Reimplantation of the inferior mesenteric artery in particular may prevent both the acute and the insidious variants of this complication in patients who undergo aortic surgery and decrease the incidence of this complication in patients with a history of radiation therapy to the pelvis.

Aged↗