Quantitative MRI in murine radiation-induced rectocolitis: comparison with histopathological inflammation score.

Murine radiation-induced rectocolitis is considered to be a relevant animal model of gastrointestinal inflammation. The purpose of our study was to compare quantitative MRI and histopathological features in this gastrointestinal inflammation model. Radiation rectocolitis was induced by localized single-dose radiation (27 Gy) in Sprague-Dawley rats. T2 -weighted, T1 -weighted and diffusion-weighted MRI was performed at 7 T in 16 rats between 2 and 4 weeks after irradiation and in 10 control rats. Rats were sacrificed and the histopathological inflammation score of the colorectal samples was assessed. The irradiated rats showed significant increase in colorectal wall thickness (2.1 ± 0.3 mm versus 0.8 ± 0.3 mm in control rats, P < 0.0001), normalized T2 signal intensity (4 ± 0.8 versus 2 ± 0.4 AU, P < 0.0001), normalized T1 signal intensity (1.4 ± 0.1 versus 1.1 ± 0.2 AU, P = 0.0009) and apparent and pure diffusion coefficients (ADC and D) (2.06 × 10-3 ± 0.34 versus 1.51 × 10-3 ± 0.23 mm2 /s, P = 0.0004, and 1.97 × 10-3 ± 0.43 mm2 /s versus 1.48 × 10-3 ± 0.29 mm2 /s, P = 0.008, respectively). Colorectal wall thickness (r = 0.84, P < 0.0001), normalized T2 signal intensity (r = 0.85, P < 0.0001) and ADC (r = 0.80, P < 0.0001) were strongly correlated with the histopathological inflammation score, whereas normalized T1 signal intensity and D were moderately correlated (r = 0.64, P = 0.0006, and r = 0.65, P = 0.0003, respectively). High-field MRI features of single-dose radiation-induced rectocolitis in rats differ significantly from those of control rats. Quantitative MRI characteristics, especially wall thickness, normalized T2 signal intensity, ADC and D, are potential markers of the histopathological inflammation score.

Glutaraldehyde-induced colitis: case reports and literature review.

Glutaraldehyde-induced colitis is an uncommon colitis in clinical practice. Because the involvement of colonic segment is determined by the endoscopic part where glutaraldehyde remains, a recent history of endoscopy and a demarcated involvement of colonic segment are the most characteristic signs of glutaraldehyde-induced colitis. The typical clinical scenario is acute onset of lower abdominal pain, fever, and bloody stool. Laboratory data usually show leukocytosis and elevated C-reactive protein. The endoscopic pictures of involved segments are compatible with acute colitis, including hyperemic, edematous, with or without multiple erosions. Acute ischemic colitis and infectious colitis should be differentiated at the outset of the disease. Stool pathogen tests are usually negative. Parenteral empiric antibiotic may be considered if severe transmural edema of the involved segment is observed in computed tomography. Conservative treatment, including bowel rest and parenteral hydration, is able to stabilize the condition in a week. Herein, we present two cases of acute proctocolitis caused by glutaraldehyde after uneventful colonoscopy.

Acute rectocolitis following endoscopy in health check-up patients--glutaraldehyde colitis or ischemic colitis?

PURPOSE: Acute rectocolitis is a rare complication that follows endoscopy. It could be caused by glutaraldehyde or ischemic injury. The clinical, endoscopic, radiological, and pathological features of glutaraldehyde-induced colitis may mimic those of ischemic colitis. We reported our experiences regarding this problem. METHODS: The medical records of patients with acute rectocolitis following endoscopy treated at Kaohsiung Veterans General Hospital since 2001 were reviewed. The indication of endoscopy was health check-up for all patients. Published English-language studies regarding acute rectocolitis following endoscopy were also reviewed. RESULTS: An outbreak of six patients occurred in April 2002 and one cirrhotic patient was admitted in July 2008. All patients developed a self-limited syndrome of abdominal pain and bloody diarrhea within 48 h of uncomplicated endoscopy. One severely ill patient required hospitalization to receive intravenous fluid and antibiotics. After the investigation in April 2002, glutaraldehyde-induced colitis was diagnosed due to a defect in the endoscope-cleansing procedure. There were no any deficiencies in the cleansing procedure in July 2008. Considering the patient's concomitant disease, we postulated that ischemic colitis with cirrhosis-related intestinal inflammation and endotoxemia was the possible diagnosis in this sporadic case. CONCLUSIONS: Endoscopists should be aware of this iatrogenic complication in patients presenting with acute rectocolitis, especially in those who have undergone recent endoscopic examination. An outbreak of acute rectocolitis following endoscopy should be considered glutaraldehyde-induced and should lead to an investigation of cleansing and equipment-disinfection procedures. In the absence of strong evidence of an outbreak, an infectious disease, or contamination of glutaraldehyde, a sporadic case should be considered ischemic colitis especially in patients with relevant concomitant diseases or predisposing factors.

Refractory proctosigmoiditis probably caused by inferior mesenteric vein ligation at sigmoidectomy.

A case of refractory proctosigmoiditis is reported in a 65-year-old female post-sigmoidectomy patient. She had bloody diarrhea and abdominal pain 2 years after sigmoidectomy, in which the inferior mesenteric vein was ligated close to the inferior mesenteric artery root during the lymph node dissection, while the inferior mesenteric artery trunk and the last branch of the sigmoid arteries was preserved. The biopsied specimen obtained by a fiber optic colonoscopy was diagnosed as proctitis. Antidiarrheals, 5-aminosalicylic acid and steroid enemas showed only limited therapeutic effects. An angiography revealed a mild degree of rectal artery dilatation and tiny venous angiogenesis detected on the delayed phase images. Because the inferior mesenteric vein had been ligated, collateral veins developed to drain the blood on the distal side of the anastomosis to bilateral internal iliac veins. The venous blood of the descending colon (oral side of anastomosis) drained to left colic vein. The cause of rectosigmoiditis was considered to be venous congestion due to the inferior mesenteric vein ligation. A rectosigmoidectomy with reanastomosis using a double-stapling technique was performed, and the patient was discharged without symptoms.

CT findings in isolated ischemic proctosigmoiditis.

The purpose of our study was to describe the CT features of ischemic proctosigmoiditis in correlation with clinical, laboratory, endoscopic, and histopathologic findings. Our study included seven patients with isolated ischemic proctosigmoiditis. Patients were identified by a retrospective review of all histopathologic records of colonoscopic biopsies performed during a time period of 4 years. All patients presented with left lower abdominal quadrant pain, bloody stools, and leukocytosis, and four patients had fever at the time of presentation. Four of seven patients suffered from diarrhea, one of seven was constipated and two of seven had normal stool consistency. The CT examinations were reviewed by two authors by consensus and compared with clinical and histopathologic results as well as with the initial CT diagnosis. The CT showed a wall thickening confined to the rectum and sigmoid colon in seven of seven patients, stranding of the pararectal fat in four of seven, and stranding of the perisigmoidal fat in one of seven patients. There were no enlarged lymph nodes, but five of seven patients showed coexistent diverticulosis and in three of these patients CT findings were initially misinterpreted as sigmoid diverticulitis. Endoscopies and histopathologic analyses of endoscopic biopsies confirmed non-transmural ischemic proctosigmoiditis in all patients. Isolated ischemic proctosigmoiditis often presents with unspecific CT features and potentially misleading clinical and laboratory findings. In an elderly patient or a patient with known cardiovascular risk factors the diagnosis of ischemic proctosigmoiditis should be considered when wall thickening confined to the rectum and sigmoid colon is seen that is associated with perirectal fat stranding.

Colitis cystica profunda: self-inflicted by rectal trauma? Report of a case.

Colitis cystica profunda (CCP) is a rare benign condition with a controversial etiology. We report a case of CCP in a patient with a history of anal masturbation, supporting an acquired traumatic etiology. Diagnosis was assisted by transrectal ultrasound. The patient was successfully treated by local excision.

[Rectal endosonography for perirectal and non-tumor rectal changes]. / Rektale endosonographie für perirektale und nichttumoröse rektale Veränderungen.

The value of rectal endosonography was retrospectively evaluated in 39 patients with various rectal and perirectal diseases. Endosonography proved to be very helpful in demonstrating or excluding abscesses. In patients with aspecific minor inflammatory rectal diseases, endosonography was not very helpful. Endosonography is complementary to other imaging techniques like CT and MRI in establishing perirectal tumors. Endosonography shows the relationship of the rectal wall with an extrarectal tumor and is capable of demonstrating the extent of smaller tumors. It may contribute to the diagnosis of endometriosis in the rectovaginal space. In patients with anal pain endosonography can play an important role in demonstrating or excluding fistulas, abscesses and other diseases.

The plain abdominal film accurately estimates extent of active ulcerative colitis.

The aim of our study was to establish whether plain abdominal film can accurately assess the extent of active ulcerative colitis. Ninety-seven ulcerative colitis patients were studied, in whom the extent of the macroscopic lesion was established either by colonoscopy (n = 75) or by resection (n = 22). Of these, 42 had proctosigmoiditis, 12 left-sided colitis, 12 subtotal colitis, and 31 total colitis. Nine well-tested features were used for the radiological classification of lesion extent. The radiologists were not given any clinical information. Seventy-eight patients (80.4%) were correctly classified by plain abdominal film (r = 0.86); the best concordance was achieved for proctosigmoiditis and total colitis (80.9 and 90.3%, respectively). In total colitis the most reliable radiological features were "irregularity of the mucosal edge" and "increased thickness of the colon wall, " which were present in 74.2 and 67.7%, respectively, of the correctly classified patients. The fourfold combination of these two features with "loss of haustral clefts" and "empty right colon" was present only in patients with total colitis, and at least one of these features was present in all but one of them. Conversely, all nine abnormalities were absent in 73.8% of patients with proctosigmoiditis. In conclusion, plain abdominal film is a reliable tool for judging the extent of lesion in active ulcerative colitis. It seems particularly accurate in total colitis, where, in the acute phases, it is most important to avoid invasive examinations.

The natural history of radiation-induced proctosigmoiditis: an analysis of 88 patients.

The records of 88 patients with radiation-induced proctosigmoidosis seen over an eight year period were reviewed. Eighty-four (95 per cent) had been irradiated for a gynaecological malignancy. The peak incidence of bleeding occurred after a latent period of nine months from the time of irradiation. Twenty-five subjects (28 per cent) had associated injury to the urinary tract. A wide spectrum of radiological abnormalities found on barium enema is described. Twenty-four patients (27 per cent) underwent operations for radiation-induced injury to the colon and urinary tract. Operations on the bowel were attended by a high complication rate (79%). A clinical classification based on bowel symptoms is presented. Those whose only symptom was low grade rectal bleeding (Group I) had the most favourable outcome and of these, 35 per cent stopped bleeding spontaneously by six months. Patients who required frequent transfusions (Group II) had an increasing mortality rate with the passage of time. Patients whose predominant symptoms were pain and bowel dysfunction (Group III) had the highest death rate but some did well after an operative procedure.

Radiology of invasive amebiasis of the colon.

Entamoeba histolytica is a protozoan that is endemic in various parts of the world, including some areas of the United States. It may live in the large bowel in its cyst form without harming the host (commensalism) or, for as yet poorly understood reasons, invade the tissues as a trophozoite producing invasive amebiasis of the colon. In a review of over 3,000 cases of invasive amebiasis, the clinico-pathologic forms of the disease were: ulcerative rectocolitis (95%), typhloappendicitis (3%), ameboma (1.5%), and fulminating colitis and toxic megacolon (0.5%). Different radiographic patterns are seen in each clinical form with varying degrees of specificity. It is vitally important that this disease be included in the differential diagnosis of large bowel pathology even in nonendemic areas. Several referral patients who have received inappropriate therapy for inflammatory bowel disease with near disastrous results are seen at one of our institutions (Loyola) each year.