Video Capsule Endoscopy

Hello, Summarians!

A GI focus today. Wouldn’t it be nice to find another way to visualize the inside of the intestinal tract? The video capsule may help with that with some limitations…

Please give me feedback on ways I can make it more useful to you.

If it is valuable to you please consider sending it on to a friend 😄 

Video Capsule Endoscopy in Dogs

Chronic enteropathy (CE) in dogs is characterized by persistent or recurring gastrointestinal symptoms such as vomiting, diarrhea, hyporexia, and weight loss. The diagnosis is made by excluding other medical conditions. CE is classified based on treatment response as food-responsive, immunosuppressant-responsive, nonresponsive, and possibly antibiotic-responsive. Traditional gastrointestinal endoscopy, though useful for obtaining biopsies from various parts of the gastrointestinal tract, has limitations such as the need for general anesthesia and incomplete evaluation of the jejunum. Video capsule endoscopy (VCE), on the other hand, offers a noninvasive method to evaluate the entire gastrointestinal tract and has been used in human medicine for over a decade. In veterinary medicine, VCE studies have been limited, mostly focusing on treatment response to antiparasiticides and the detection of bleeding lesions. 

The present study aimed to investigate the safety and effectiveness of using the ALICAM video capsule in dogs with CE weighing over 10 kg and to compare the gastrointestinal morphology of CE dogs with healthy controls (HCs). Results showed that VCE was a safe and feasible method for assessing the gastrointestinal mucosa, with complete studies obtained in all dogs and no instances of capsule retention. There were no significant differences between CE and HC dogs regarding the number, severity, or extent of macroscopic gastrointestinal abnormalities. The findings suggest that macroscopic abnormalities commonly attributed to gastrointestinal disease could also occur in healthy dogs, complicating the interpretation of such lesions. 

A similar number of CE and HC dogs had dilated lacteals in the proximal small intestine, which are typically associated with gastrointestinal disease in dogs. However, none of the HC dogs developed clinical signs within a year of the study, suggesting that these findings may represent normal variation. In human studies, a proportion of healthy individuals were found to have lymphangiectasia, raising questions about the clinical relevance of this observation in dogs. 

Although VCE has limitations, such as the inability to obtain biopsies and reduced visualization in the colon, it allows for full evaluation of the small intestine and avoids complications associated with anesthesia. The study did not find significant differences in macroscopic findings between CE and HC dogs, suggesting that these abnormalities might not always be indicative of disease. Furthermore, VCE could be an effective method for detecting gastrointestinal ulcerations. 

The study had limitations, including a relatively small sample size, the inclusion of mostly dogs with moderate gastrointestinal disease, and slight variations in breed, age, sex, and body weight between groups. Despite these limitations, the study concluded that VCE is a safe and feasible diagnostic method in dogs with CE and healthy controls over 10 kg. Future studies are recommended to explore the findings further, especially in dogs with severe gastrointestinal disease, and to establish the clinical significance of macroscopic gastrointestinal abnormalities in both healthy and diseased dogs. 

Holmberg J, Ljungvall I, Pelander L, et al. Video capsule endoscopy findings in dogs with chronic enteropathy and in healthy dogs. J Vet Intern Med. 2024; 38(5): 2454-2463. doi:10.1111/jvim.17168 

Bottom line — May be useful in certain situations.

Fecal Transplants for Diarrhea in Foals

Diarrhea affects up to 80% of foals in their first six months and is often associated with both infectious agents and dysbiosis, a disruption of the intestinal microbial communities. While supportive treatments like fluids and nutritional support are common, they do not address dysbiosis. Probiotics have been tried but sometimes worsen the condition. Fecal microbiota transplantation (FMT) has shown mixed results in adult horses, and its effects in foals had not been previously studied. 

This study aimed to investigate the clinical outcomes and changes in fecal microbiota associated with FMT in foals with diarrhea. The hypothesis was that FMT would improve clinical signs, resolve diarrhea, and restore normal fecal microbiota. The study found that foals receiving FMT showed improvement in certain clinical and clinicopathological variables, such as reduced heart rate, white blood cell count, and packed cell volume, along with increased serum chloride levels. These changes suggest improved hydration, better hemodynamic status, and reduced intestinal inflammation in treated foals. 

Although there were no significant differences between the FMT and control groups in terms of diarrhea resolution and survival rates, the potential beneficial effects of FMT cannot be discounted. Two foals initially in the control group who did not improve were later given FMT and subsequently showed resolution of diarrhea. This suggests that FMT may have contributed to their recovery, although continued supportive care could also have played a role. 

Bell J, Raidal SL, Cuming RS, Trope G, Hughes KJ. Effects of fecal microbiota transplantation on clinical outcomes and fecal microbiota of foals with diarrhea. J Vet Intern Med. 2024; 38(5): 2718-2728. doi:10.1111/jvim.17185 

Bottom line — Appears to be safe but more study is needed on efficacy.

Fat Soluble Vitamins and IBD

Vitamins A, D, and E are essential fat-soluble nutrients in dogs that play critical roles in growth, reproduction, and immune regulation. Since dogs cannot synthesize these vitamins in sufficient amounts, they must obtain them through their diet. Diseases that impair fat absorption, such as intestinal lymphangiectasia, inflammatory bowel disease (IBD), and chronic enteropathy (CE), can lead to deficiencies in these vitamins. In humans, vitamin D is crucial for immune tolerance and maintaining the intestinal barrier, with deficiencies linked to increased severity of intestinal inflammation and higher risks of hospitalization and mortality in IBD patients. Vitamin A interacts with vitamin D receptors and is involved in immune responses, while vitamin E acts as an antioxidant that improves immune function by scavenging free radicals and suppressing proinflammatory cytokines. 

This study hypothesized that dogs with CE would have decreased concentrations of vitamins D and A. The aims were to determine whether serum concentrations of these vitamins differed between dogs with CE and healthy dogs, and to identify any correlations with clinical signs, disease activity indexes, and laboratory variables. The findings revealed that dogs with CE had significantly lower levels of 25(OH)D (vitamin D) compared to healthy dogs, consistent with previous research. Notably, only 35% of the dogs with CE had 25(OH)D concentrations below the reference interval. These dogs often exhibited severe clinical signs such as being underweight, experiencing vomiting, having poor fecal scores, and displaying laboratory abnormalities like hypoalbuminemia and hypocalcemia. 

Contrary to expectations, some dogs with CE had higher concentrations of retinol (vitamin A) and α-tocopherol (vitamin E) than healthy dogs. Retinol levels were increased in dogs with CE, although retinol is considered a late indicator of vitamin A deficiency and may not reflect mild deficiencies. The variability in α-tocopherol concentrations was also higher among dogs with CE, with most healthy dogs having levels above the normal reference range. The study suggests that alterations in vitamin A and E metabolism may occur in dogs with CE, but the clinical relevance of these findings remains unclear. 

The study concludes that dogs with CE, especially those showing severe clinical signs and laboratory abnormalities like low serum calcium and albumin, should be monitored for decreased vitamin D levels. While the benefits of supplementing vitamins A and E in these cases are not yet clear, further research is needed to understand their roles and to establish evidence-based guidelines for supplementation. Limitations of the study include a small sample size, lack of diet and treatment standardization, and a control group that may not be fully representative due to differences in age and living conditions compared to the case group. 

Serafini F, Maxwell KM, Zhu X, Lennon EM. Dysregulated serum concentrations of fat-soluble vitamins in dogs with chronic enteropathy. J Vet Intern Med. 2024; 38(5): 2612-2619. doi:10.1111/jvim.17107 

Bottom line — Supplementation may be needed.

Just putting things in perspective …