Short colon syndrome in cats.

BACKGROUND: Shortening of the colon has been described in cats, but its imaging and clinicopathological features remain poorly understood. OBJECTIVES: Description of the signalment, clinical presentation, imaging, endoscopic and histological features of short colon syndrome in cats. ANIMALS: Ninety-three cats diagnosed with short colon. METHODS: Multi-institutional, descriptive, retrospective case series study. Medical records were searched for a diagnosis of short colon on abdominal ultrasonography, computed tomography, endoscopy, autopsy, or a combination of these modalities. RESULTS: The median age of included cats was 12 years at the time of diagnosis. Diarrhea was the most common clinical sign (60/92; 65%), followed by vomiting (36/92; 39%), weight loss (36/92; 39%), and inappetence (24/92; 26%). Thirteen percent of cats (12/92) had no signs of gastrointestinal disease at the time of diagnosis. In addition to a shortened colonic length, 79% (66/84) of cats had concomitant colonic thickening on ultrasonographic examination. On colonoscopy, mucosal ulcerations of the colonic wall were seen in 39% (9/23) of cats. Histopathologically, all cats but 1 (diagnosed simultaneously with colonic small cell lymphoma) had lymphoplasmacytic colitis, and when small intestinal biopsies were performed, concurrent lymphoplasmacytic enteritis or small cell lymphoma of the small intestine. CONCLUSIONS AND CLINICAL IMPORTANCE: Lymphoplasmacytic colitis is seen commonly in cats with short colon, suggesting a potential link between these entities.

ACUTE ABDOMINAL COMPARTMENT SYNDROME DURING COLONOSCOPY IN A WESTERN LOWLAND GORILLA (GORILLA GORILLA GORILLA).

A novel case report of acute abdominal compartment syndrome (ACS) with respiratory and hemodynamic collapse during colonoscopy in a western lowland gorilla (Gorilla gorilla gorilla), notably, without colonic perforation is presented here. ACS is a rapidly progressive and sustained increase in intra-abdominal pressure leading to shock with multisystem organ failure. Surgical intervention was mandatory, and abdominal decompression was immediately life-saving, although the patient died 1 wk later of surgical complications. Colonoscopy is a widely performed procedure that is generally considered safe, and serious complications during colonoscopy are rare. ACS has been previously reported during colonoscopy with perforation in four cases (human)1,4,6,8. In this instance there was no evidence of perforation, representing not only a rare complication of the procedure, but also a novel cause of ACS. This is the first report of ACS in a nonhuman primate and of nonperforation-associated ACS in human or nonhuman primates.

Transanal access port (TrAAP) technique: the use of a single incision laparoscopic surgical port during canine colonoscopy (a cadaveric study).

BACKGROUND: Transanal colonoscopy using the single-incision laparoscopic surgical port is routinely used in human patients but has not been described in veterinary literature. The purpose of this study was to describe a novel access technique elucidating its endoscopic clinical potential and benefits. Additionally, its challenges, limitations, and clinical usability will be discussed and critiqued. The aim of this study was to describe the feasibility of the single-incision laparoscopic surgical port (SILS) as a transanal access technique in canine cadavers and compare its technical capabilities and economic value when compared to the traditional approaches of digital pressure and purse string. RESULTS: The overall time to reach an intraluminal pressure of 10 mmHg was faster for digital pressure versus purse string (p = 0.05) and faster for single-incision laparoscopic surgical port versus purse string (p < 0.02). Maximum luminal pressure was significantly higher between single-incision laparoscopic surgical port and purse string (p = 0.001). Mean pressure for both the complete 60 s trial and during the last 45 s of insufflation were highest with the SILS port and were significantly different between the single-incision laparoscopic surgical port versus purse string (p = 0.0001, p < 0.0001) and digital pressure versus purse string (p < 0.005, p < 0.01) respectively. Complete luminal distention and visualization was observed in all trials. CONCLUSIONS: The SILS port in a cadaveric canine model allowed good visualization of the rectal and colonic mucosa, provided constant insufflation of the colon and was feasible and subjectively easy to perform. Technical differences between techniques were observed with the use of the SILS port allowing for potentially lower personnel requirements, less procedural associated cost, less variability versus the digital pressure technique between assistants, and the ability of additional instruments to be used for procedures.

Successful implementation of intestinal endoscopy in non-human primates prompts the possibility of achieving AIDS longitudinal intestinal research.

HIV infection induces pathological changes in the intestinal mucosa. Here, a successful endoscopy was performed on the colon of a Chinese rhesus macaque by using Olympus CV170 gastroscope. The stability on postoperative recovery and the integrity of biopsy tissue implied a possibility of achieving AIDS longitudinal intestinal research on macaques.

Colonoscopic and histologic features of rectal masses in dogs: 82 cases (1995-2012).

OBJECTIVE To evaluate colonoscopic and histologic features of rectal masses in dogs. DESIGN Retrospective case series. ANIMALS 82 client-owned dogs with rectal masses that underwent colonoscopy. PROCEDURES Medical records of dogs with rectal masses that underwent colonoscopy were reviewed. History, signalment, clinical signs, results of physical examination, diagnostic imaging findings, and results of colonoscopy (including complications) were recorded. When available, tissue samples obtained during colonoscopy and by means of surgical biopsy were reviewed by a single board-certified pathologist. Histologic features and tumor grade (when applicable) of tissue samples obtained during colonoscopy versus surgical biopsy were compared. RESULTS Multiple rectal masses were observed during colonoscopy in 6 of the 82 dogs, but no lesions were visualized orad to the colorectal junction. Results of histologic evaluation of surgical biopsy specimens were consistent with a diagnosis of epithelial neoplasia in 58 of 64 dogs, of which 71% were classified as benign adenoma or polyp and 29% were classified as adenocarcinoma in situ or adenocarcinoma. Complications of colonoscopy occurred in 3 of 82 dogs but were considered minor. A discrepancy in diagnosis occurred in 5 of 16 dogs for which both colonoscopic and surgical biopsy samples were available for histologic review. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that multiple rectal masses are uncommon in dogs, and secondary lesions orad to the colorectal junction were not found in this study. Colonoscopy was associated with few complications, but the need for colonoscopic assessment of the entire colon in this patient population may merit reevaluation.

Ultrasonographic, endoscopic and histological appearance of the caecum in clinically healthy cats.

Objectives The aim of the study was to describe the ultrasonographic and endoscopic appearance and characteristics of the caecum in asymptomatic cats, and to correlate these findings with histology. Methods Ex vivo ultrasonographic and histologic evaluations of a fresh caecum were initially performed. Then, 20 asymptomatic cats, privately owned or originating from a reproductive colony, were recruited. All cats had an ultrasonographic examination of the ileocaecocolic junction, where the thickness of the caecal wall, ileocolic lymph nodes and the echogenicity of the local fat were assessed. They all underwent a colonoscopy with a macroscopic assessment of the mucosa and biopsies for histology. Results An ultrasonographic hypoechoic nodular inner layer, which corresponded to the coalescence of multiple lymphoid follicles originating from the submucosa and protruding in the mucosa on histology, was visible in all parts of the caecum. The combined mucosa and submucosa was measured ultrasonographically and defined as the follicular layer. Although all cats were asymptomatic, 3/19 cats showed mild caecal inflammation on histology. The most discriminatory ultrasonographic parameter in assessing this subclinical inflammation was the thickness of the follicular layer at the entrance of the caecum, with a cut-off value of 2.0 mm. All cats (20/20) showed some degree of macroscopic 'dimpling' of the caecal mucosa on endoscopy. Conclusions and relevance Lymphoid follicles in the caecal mucosa and submucosa constitute a unique follicular layer on ultrasound. In asymptomatic cats, a subtle, non-clinically relevant inflammation may exist and this is correlated with an increased thickness of the follicular layer on ultrasound. On endoscopy, a 'dimpled aspect' to the caecal mucosa is a normal finding in the asymptomatic cat.

Ultrasonographic, endoscopic and histological appearances of the caecum in cats presenting with chronic clinical signs of caecocolic disease.

Objectives This study aimed to describe the ultrasonographic, endoscopic and histological characteristics of the caecum and ileocaecocolic junction in cats suffering from chronic clinical signs compatible with caecocolic disease. Methods Cats presenting with clinical signs suggestive of a caecocolic disease were prospectively recruited. All cats underwent an ultrasonographic examination of the caecum, ileum, colon, ileocolic lymph nodes and local mesenteric fat, in addition to comprehensive abdominal ultrasonography. This was followed by a colonoscopy with a macroscopic assessment of the caecocolic mucosa; caecocolic tissue samples were systematically collected for histologic analysis. Results Eighteen cats were included. Eleven of 18 cats had ultrasonographic abnormalities adjacent to the ileocaecocolic junction (lymphadenopathy, local steatitis) and 13/18 cats had abnormalities directly related to the junction (wall thickening, loss of wall layering). Seventeen of 18 cats had at least one ultrasonographic abnormality. Endoscopically, hyperaemia, oedema, discoloration and/or erosions were found in all cats. Each cat was classified as having mild or moderate-to-severe lesions according to endoscopic results; no classification could be established statistically for ultrasonographic results. The accentuation of the dimpled pattern tended to be inversely related to the severity of endoscopic lesion scoring. Histologically, a large proportion of cats showed typhlitis (13/16), one had lymphoma and two were normal. All cats with typhlitis also had colitis. There was only slight agreement between endoscopic and histological caecal results regarding the severity of lesions. Loss of caecal wall layering on ultrasound was found in 7/18 cats and, surprisingly, did not appear as a reliable predictor of the severity of inflammation or of malignancy; neither did local steatitis nor lymph node size. Conclusions and relevance Ultrasonography and endoscopy should not be used as the sole methods to investigate the ileocaecocolic region in cats with clinical signs suggestive of caecocolic disease. The presence of chronic clinical signs should routinely prompt histological biopsy.

Use of endoscopic-assisted argon plasma coagulation for the treatment of colonic vascular ectasia (angiodysplasia) in an adult dog.

CASE DESCRIPTION: A 10-year-old neutered male mixed-breed dog was evaluated for a 5-year history of intermittent hematochezia and chronic anemia that were unresponsive to medical treatment. CLINICAL FINDINGS: Colonoscopy revealed multifocal areas of coalescing tortuous mucosal blood vessels throughout the colon and rectum. Colonic vascular ectasia (angiodysplasia) was diagnosed on the basis of the endoscopic appearance of the lesions. TREATMENT AND OUTCOME: The dog failed to respond to traditional medical treatments for colonic vascular ectasia and required multiple plasma and blood transfusions. The dog received 4 endoscopic-assisted argon plasma coagulation treatments, which resulted in long-term resolution of gastrointestinal hemorrhage. Colonic perforation occurred during the third argon plasma coagulation treatment. The perforation was surgically repaired. The dog remained free from clinical signs of colonic vascular ectasia for > 1 year after the third argon plasma coagulation treatment and was euthanized because of clinical deterioration associated with progressive heart disease. CLINICAL RELEVANCE: Endoscopic-assisted argon plasma coagulation treatment is a novel treatment for dogs with colonic vascular ectasia and provided long-term resolution of clinical signs for the dog of this report. In human patients, complications associated with endoscopic-assisted argon plasma coagulation treatment include colonic perforation, which also occurred in the dog of this report.

Burrowing is a sensitive behavioural assay for monitoring general wellbeing during dextran sulfate sodium colitis in laboratory mice.

An impaired intestinal epithelial barrier is thought to be a major factor in the pathogenesis of human inflammatory bowel disease (IBD). IBD is frequently investigated by inducing a damaged barrier in murine models of colitis. This can be done by feeding mice with dextran sulfate sodium (DSS) polymers in their drinking water. Refinement measures should focus on alleviating unnecessary suffering during this probably painful condition. Appropriate parameters are needed to decide when to terminate the experiments. Our aim was to investigate whether a change in burrowing behaviour is a sensitive measure of animal welfare in murine models of colitis. Acute colitis was induced in C57BL/6 mice with 2.0% DSS over nine days. The burrowing test is based on the species-typical behaviour of mice to spontaneously displace items from tubes within their home cage. As a burrowing apparatus, a water bottle (250 mL, 150 mm length, 55 mm diameter) filled with 138-142 g of pellets of the animal's diet was used. The presence of intestinal inflammation as a result of acute DSS-induced colitis was confirmed by a decrease in body weight, colon length and an increase of murine endoscopic index of colitis severity, histological score and spleen weight in the group receiving DSS as compared with the control group. An onset of intestinal inflammation correlated with a significant decrease in burrowing behaviour (P < 0.05). Altered adrenal gland histology indicated stress as a result of acute colitis. Our findings provide evidence that changes of spontaneous burrowing behaviour correlate with the onset of inflammation in acute DSS-induced colitis.

Adapter-modified Ussing chamber enables evaluation of endoscopically-obtained colonic biopsy samples from cats and dogs.

Adapter-modified Ussing chambers have been used for assessment of endoscopically obtained intestinal biopsies in humans. The aim of this study was to evaluate the feasibility of an adapter-modified Ussing chamber for assessment of intestinal transport physiology in endoscopically-obtained colonic biopsies from cats and dogs. Fifteen colonic biopsies from four cats and 13 colonic biopsies from four dogs were transferred into a modified Ussing chamber and sequentially exposed to several compounds. Baseline mean±SD conductance was measured. Changes of short circuit current (ΔIsc) were observed after exposure to glucose (number of feline biopsies that responded=0/number of canine biopsies that responded=4), phloridzin (n=0/n=7), histamine (n=5/n=12), serotonin (n=7/n=12), prostaglandin (n=5/n=7), forskolin (n=7/n=7), and ouabain (n=9/n=7). The adapter-modified Ussing chamber studied here enables investigation of transport physiology of endoscopically-obtained colonic biopsies from companion animals. However, we observed a large variability of results, suggesting that clinical use of this method is limited.

Chronic idiopathic large bowel diarrhea in the dog.

Chronic idiopathic large bowel diarrhea (CILBD) is a descriptive diagnosis reached by exclusion of the most common diseases associated with chronic large bowel diarrhea. The most important features of irritable bowel syndrome in people are reviewed. The authors report 19 new cases of CILBD that they compare with 37 cases from the literature. The disease appears to be common among dogs referred for colonoscopy. Many dogs with CILBD experience behavioral problems or are exposed to a stressful environment. Most dogs respond to diet change and fiber supplementation. Some benefit from behavior-modifying therapy.

Endoscopic polypectomy using endocautery in three dogs and one cat.

Endoscopic polypectomy has long been employed in humans with either gastric or colonic polyps. Despite the frequency of use in humans, reports in veterinary medicine remain scarce. The medical records of three dogs and one cat were reviewed. Two animals that were presented with hematochezia underwent colonoscopic polypectomy and were clinically normal 22 months and 6 months postpolypectomy. One animal that was presented with chronic vomiting underwent gastric polypectomy and was clinically normal 21 months postpolypectomy. One animal with an incidentally discovered gastric polyp underwent polypectomy without complication. Endoscopic polypectomy may be a viable alternative to surgery in veterinary patients with gastric or colonic polyps.

Safety and efficacy of oral low-volume sodium phosphate bowel preparation for colonoscopy in dogs.

BACKGROUND: Sodium phosphate (NaP) is a low-volume, hyperosmolar laxative that is an effective bowel-cleansing agent in humans. HYPOTHESIS: NaP will be as safe and efficacious as polyethylene glycol (PEG) bowel preparation for colonoscopy in dogs. ANIMALS: Eight purpose-bred healthy dogs. METHODS: In phase I, standard (NaP and enemas; NaP(1)) and control preparations (PEG and enemas) were compared in a crossover design to determine the safety and efficacy of NaP. Serial clinical and serum analytical evaluations were used to determine the safety of NaP. In phase II, the efficacy of the standard NaP preparation was compared with 3 other NaP variations, which excluded enema or included bisacodyl, with or without enemas in a crossover design. An observer blinded to the bowel preparation assigned a score of 1-4 (1=clean colon; 4=unacceptable colon cleansing preventing adequate endoscopic evaluation) to each of 5 regions of the colon. RESULTS: The mean total colon cleansing score (TCS), defined as the sum of scores from each region, of the control (9.4) was less than NaP(1) (13.6) (P < 0.05). There were no significant differences in regional or TCS for the remaining 4 NaP protocols. NaP(1) resulted in moderate, but clinically occult, hyperphosphatemia and hypocalcemia, which resolved within 24 hours. CONCLUSIONS AND CLINICAL IMPORTANCE: Despite the safety and ease of administration of the NaP preparations, the NaP bowel-cleansing preparations used in this study cannot be recommended for use because of the inadequate quality of bowel preparation compared with the protocol using PEG-containing fluids.

Effects of the macrolide drug tylosin on chronic diarrhea in rhesus macaques (Macaca mulatta).

Diarrhea is the gastrointestinal disease most frequently encountered in captive rhesus macaques. The precise pathogenic mechanisms underlying chronic diarrhea in nonhuman primates are not well understood, but a persistent inflammatory component has been implicated strongly. This study evaluated the inflammatory changes in the colon of macaques with diarrhea and assessed the efficacy of a 10-d course of tylosin in a cohort of 21 animals with chronic diarrhea. Stool quality was evaluated daily, and fecal consistency was scored. Colonoscopies were performed; biopsy samples were characterized histologically and assayed for expression of TNFalpha mRNA. Blood samples collected pre-, mid-, and post-treatment were assayed for C-reactive protein (CRP). The results indicated that 63% of the animals receiving tylosin showed improvement in stool quality, compared with 10% in the sham-treated group. Histologically, 82% of animals in the tylosin-treated group had a reduction in the severity of colonic lesions post-treatment, compared with 40% of animals in the sham group. The amount of TNFalpha mRNA before treatment did not differ from that afterward in either tylosin- or sham-treated animals. CRP levels serially decreased in tylosin-treated monkeys; the average post-treatment CRP value for tylosin-treated animals was 11.96 +/- 3.86 microg/ml compared with 26.48 +/- 4.86 microg/ml for sham-treated controls. In conclusion, tylosin significantly improved the fecal consistency score, significantly decreased colonic inflammation, and significantly decreased serum CRP levels post-treatment in rhesus macaques with chronic diarrhea.

Murine microvideo endoscopy of the colonic microcirculation.

Natural orifice endoscopy in small animal models has been limited in the past by instrument size and optical performance. In this report, we investigate the feasibility of using a recently developed microvideo endoscopy system to evaluate the colon microcirculation. Using a murine model of acute colitis, microvideo endoscopy was useful in mapping the topography of inflammation as well as identifying relevant structures in the microcirculation. We conclude that natural orifice endoscopy is a useful method for the minimally invasive longitudinal assessment of the colonic mucosal microcirculation.

Evaluation of colonoscopic allergen provocation as a diagnostic tool in dogs with proven food hypersensitivity reactions.

OBJECTIVE: To evaluate the colonoscopic allergen provocation (COLAP) test as a new tool for the diagnosis of IgE-mediated food allergy. METHODS: Oral food challenges as well as COLAP testing were performed in a colony of nine research dogs with proven immediate-type food allergic reactions. In addition, COLAP was performed in five healthy dogs. RESULTS: When compared with the oral challenge test, COLAP accurately determined 18 of 23 (73 per cent) positive oral challenge reactions (73 per cent) in dogs with food allergies and was negative in the healthy dogs. CLINICAL SIGNIFICANCE: The accuracy of this new test may be higher than that for gastric sensitivity testing. Therefore, COLAP holds promise as a new test to confirm the diagnosis of suspect IgE-mediated food allergy in dogs.

Complications associated with 355 flexible colonoscopic procedures in dogs.

Flexible colonoscopy is commonly performed in dogs with signs of large-bowel diseases. Although considered to be a safe procedure, no reports of complications associated with colonoscopy have appeared in the veterinary literature. The purpose of this study was to describe the frequency and types of adverse events that developed during flexible colonoscopy in dogs. Medical records were reviewed from 355 scheduled colonoscopic procedures. Major complications were defined as adverse events in which the dog's life was potentially jeopardized and the complication required intensive treatment or monitoring. Major complications consisting of fatal aspiration of GoLYTELY, colonic perforation, and excessive hemorrhage after biopsy of an adenocarcinoma with rigid forceps occurred in 3 (0.85%) dogs. Minor complications associated with anesthesia or colonoscopy occurred during 3.4% of procedures. Complications were classified as minor if the adverse event required minimal treatment or monitoring, and the complication was not considered a threat to the dog's life. Vomiting of GoLYTELY occurred with the administration of 4.6% of doses in 6.5% of dogs. When administering GoLYTELY, clinicians should be prepared to rapidly remove the orogastric tube and mouth speculum if vomiting occurs to reduce the potential for aspiration. In this group of dogs undergoing flexible colonoscopy, major complications occurred infrequently and minor complications developed uncommonly. Overall, minor or major complications developed during 30 (8.5%) of 355 procedures. Mortality was rare (0.28%). Flexible colonoscopy appears to be a safe procedure in dogs with signs of large-bowel diseases.

Protothecal colitis in a German shepherd dog.

A 3 1/2-year-old intact male German Shepherd Dog was admitted with a history of protracted haemorrhagic diarrhoea and tenesmus. Clinical evaluation revealed thickening of the rectal mucosa and presence of fresh blood and mucus in the faeces. Severe mucosal granularity and multiple nodules, in addition to a rectal stricture 7 to 9 cm from the anus, were found on colonoscopy. Histopathological evaluation of biopsy specimens identified organisms with morphologic features compatible with those reported for Prototheca spp. Although surgical excision of the rectal stricture was performed and ketoconazole treatment was instituted postoperatively, the dog's clinical condition deteriorated and euthanasia was performed 4 months later.

Colonoscopy, proctoscopy, and ileoscopy.

Colonoscopy and proctoscopy are primarily performed on dogs and cats with signs of chronic large bowel or rectal disease, and ileoscopy is typically performed in patients with signs of either large or small bowel disease. These techniques should not be used indiscriminately but only on animals that have a reasonable chance to benefit from their use. Even then, the techniques must be performed carefully so that the results are meaningful instead of misleading. We first consider what does and what does not constitute a reasonable indication for endoscopic examination of the lower intestines. After that, we turn to the specific techniques involved.