Vet360, December 2016 - Page 15

GASTRO-ENTEROLOGY Article reprinted with the permission of Advanstar. The article was originally printed in VETERINARY MEDICINE December 2014. VETERINARY MEDICINE is a copyrighted publication of Advanstar. Communications inc. All rights reserved. Practical Gastroinstestinal Function Testing Albert E. Jergens, DVM, PhD, DACVIM Department of Veterinary Clinical Sciences Iowa State University These tests can help narrow down your differential veterinary diagnoses for chronic enteropathies. Chronic enteropathies are common in dogs and cats and include adverse reactions to food, idiopathic inflammatory bowel disease (IBD), and antibiotic-responsive diarrhoea. While definitive diagnosis often requires collecting mucosal biopsy samples for histopathologic evaluation, noninvasive laboratory tests are useful in diagnosing these disorders and monitoring treatment. Tests for small intestinal function and disease Cobalamin The physiologic mechanism of cobalamin (vitamin B12) is complex and requires a functioning digestive system. Major disorders that interfere with cobalamin uptake include exocrine pancreatic insufficiency, distal or diffuse small intestinal disease, and excessive bacterial utilisation of cobalamin associated with bacterial dysbiosis. Hypocobalaminaemia is most often seen with long-standing and severe intestinal disease (IBD, lymphoma, or fungal enteritis) affecting the small intestine. Measuring serum cobalamin concentrations in animals with chronic enteropathies is important since failure to recognise this deficiency may result in delay of clinical recovery. Importantly, low serum cobalamin concentrations have been shown to be a risk factor for negative outcome in dogs with chronic enteropathies, including IBD and protein-losing enteropathy (PLE). If low concentrations are detected, appropriate dosages of cyanocobalamin are typically administered subcutaneously once a week, with serum concentrations reassessed at four- to six-week intervals. Folate This water-soluble vitamin (vitamin B9) is abundant in canine and feline diets, making nutritional deficiencies unlikely. Folate concentrations are typically measured in concert with cobalamin and may provide information indicative of small intestinal dysbiosis or proximal small intestinal mucosal disease. Note that serum folate concentrations may be influenced by bacterial production of folate and are therefore a less sensitive indicator of small intestinal disease than cobalamin. Citrulline This amino acid is synthesised predominantly by intestinal enterocytes. Citrulline has been shown to be a marker of functional enterocyte metabolic mass, and preliminary studies have shown plasma citrulline concentrations are significantly decreased in dogs with parvovirus enteritis. Thus, citrulline might serve as a potential marker of spontaneous and acute intestinal dysfunction. However, additional clinical trials evaluating this marker are warranted. Evaluation of intestinal protein loss PLEs are a heterogeneous group of disorders characterised by enteric loss of plasma proteins. Common causes of PLE include inflammatory enteropathi •Μ°₯Ή™•Ρ₯½Ύ•ΉΡ•Ι₯Ρ₯Μ°±ε΅Α‘…Ή₯•Ρ…Ν₯„°₯ΉΡ•ΝΡ₯Ή…°Ή•½Α±…Ν₯„°…Ή΅…Ι­•΅₯Ι½‰₯…°₯΅‰…±…Ή•ΜΈ5½ΝЁ…Ή₯΅…±Μ)•α‘₯‰₯Ёё”±…ΝΝ₯Œ±₯Ή₯…°Ν₯ΉΜ½˜•΅…₯…Ρ₯½Έ…Ή)έ•₯‘Ё±½ΝΜ°…ΉΑ…Ή‘εΑ½ΑΙ½Ρ•₯Ή•΅₯„₯́½™Ρ•Έ™½ΥΉ)½Έ±…‰½Ι…Ρ½Ι䁕م±Υ…Ρ₯½ΈΈ)%Ё₯́₯΅Α½ΙΡ…ΉΠΡΌ™₯ΙΝЁΙΥ±”½ΥЁ½Ρ‘•Θ…Ύ͕½˜‘εΑ½…±‰Υ΅₯Ή•΅₯„‘Υ”ΡΌ±½΅•ΙΥ±…ȁ₯Ή©ΥΙ䁅Ή‘•Α…Ρ₯Œ)™…₯±ΥΙ”½Θ₯ΉΝΥ™™₯₯•ΉδΈ•™₯Ή₯Ρ₯Ω”‘₯…Ή½Ν₯́½˜A1Ι•ΕΥ₯ɕ́ё”½±±•Ρ₯½Έ…Ή‘₯ΝΡ½Α…Ρ‘½±½₯Œ…ΝΝ•ΝΝ΅•ΉΠ)½˜΅Υ½Ν…°‰₯½ΑΝδΝ…΅Α±•ΜΈ)…•…°Δ΅A$)Έ1%M…Νͅ䁙½ΘΡ‘”΅•…ΝΥΙ•΅•ΉΠ½˜™•…°…±Α‘„(Δ΅ΑΙ½Ρ•₯Ή…Ν”₯Ή‘₯‰₯Ρ½Θ€‘Δ΅A$€‘…́‰••ΈΩ…±₯‘…Ρ•₯Έ)‘½Μ…Ή΅…䁉”ΥΝ•ΡΌ…ΝΝ•Ν́ΑΙ½Ρ•₯Έ±½Ν́₯ΈΡ‘”)…ΝΡΙ½₯ΉΡ•ΝΡ₯Ή…°€‘$€ΡΙ…ΠΈΥ”ΡΌΡ‘”Υ΅‰•ΙΝ½΅”)Ι₯Ρ•Ι₯„™½Θ½±±•Ρ₯Ήœ΅Υ±Ρ₯Α±”™•…°Ν…΅Α±•Μ°Ρ‘”±…ˆ΄()%ΝΝΥ”€ΐ؁π 5 H€ΘΐΔ؁π€ΔΤ((0