I'mCustomerand I would be glad to help with your question about Luna. Despite the negative tests for parasites, make sure she has been dewormed with fendbendazole (i.e. Panacur) to treat for common worms in the event of false negative tests. I would also suggest a round of metronidazole as presumptive treatment for clostridial bacterial overgrowth. I would also advise a daily probiotic such as Canine Fortiflora by Purina. Please also consider eliminating the raw portion of her diet especially if it is not commercially prepared: as you likely know, raw foods can contain organisms that can cause GI problems such as pathogenic strains of E. Coli, clostridium, Toxoplasmosis just to name a few. Make sure the kibble you are feeding is prescription hypoallergenic food and not an over the counter limited ingredient food. I understand that the prescription food is expensive but so are all the other tests that may be needed if it turns out that this is not a problem that can be managed with diet change. It usually takes 2 weeks on a specific diet (i.e. no other food or treats of any kind) to determine if it will be helpful to your dog. By 4 weeks on a prescription diet, you will know if your dog's stool is going to be normal (i.e. no unformed) and should appreciate some weight gain. If the hypoallergenic diet fails, then you could consider a trial on a high fiber diet such as Hill's w/d which is beneficial to some dogs that have large bowel inflammation (i.e. colitis): 2-4 weeks on that kind of diet is required to see if it will help.
If the above plan of action fails to resolve the issue, then other diagnostics are in order. I would advise a baseline cortisol test to rule-out atypical Addison's disease (i.e. decreased production of cortisol by the adrenal glands). If the value is less than 2, then an ACTH Stim test is in order to confirm a diagnosis of Addison's disease which is treatable with corticosteroids and other drugs as needed. I would also suggest that a PLI, cobalamin and folate tests are run to assess for pancreatitis (i.e. different than exocrine pancreatic insufficiency), bacterial overgrowth and intestinal malabsorption. The results of that test may indicate the need for specific additional therapy such as supplementation with pancreatic enzymes, long term antibiotic use and/or injectable cobalamin (B12). Beyond that, abdominal ultrasound would be the next logical step to assess the intestines and other organs. If thickening of the intestinal tract is evident, it is suggestive of inflammatory bowel disease. Endoscopic or surgical biopsies may be helpful in confirming inflammatory bowel disease (IBD) provided all other options have been exhausted prior to pursuing this kind of invasive procedure. Dogs with IBD can be managed with a variety of therapies and sometimes require use of prednisone especially in the early stages of treating the disease. Because their can be many negative side effects including changes to the intestines that makes biopsy results difficult to interpret, I do not recommend using steroids for intestinal disease in young dogs without having ruled out all other causes of loose stool and weight loss AND having intestinal biopsies to confirm the diagnosis of IBD.
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