An increase in BUN and BUN:creatinine ratio levels was observed over ≈5 months prior to presentation for recheck evaluation. Because Romeo was able to tolerate deracoxib and had no outwardly detectable adverse effects from NSAID administration, his increased BUN was initially attributed to GI injury secondary to chemotherapy and radiation therapy, but no improvement was shown with omeprazole and sucralfate treatment following chemotherapy. Deracoxib was continued because of the severity of Romeo’s orthopedic disease and potential benefits of cyclooxygenase-2 inhibition in the treatment of bladder carcinomas. Although Romeo was clinically healthy, his BUN levels continued to increase following cessation of radiation therapy and during the weeks in which chemotherapy was not administered. He was treated with sucralfate slurry (500 mg PO q8h) and omeprazole (1 mg/kg PO q12h) for 2 weeks, and CBC and serum chemistry profile were evaluated at regular intervals; however, his BUN and BUN:creatinine levels continued to increase. A video capsule endoscopy (VCE) was performed to investigate the possibility of subclinical GI bleeding and revealed multiple hemorrhages in the distal small intestine (Figure; see Treatment at a Glance). Treatment with deracoxib was discontinued after VCE was performed.
VCE has been used in dogs with unexplained causes of microcytosis, iron-deficiency anemia, or hypoalbuminemia to determine whether the cause was related to GI bleeding.1 VCE should be reserved for dogs weighing >9.5 lb (4.3 kg) because the size of the capsule restricts its use in smaller dogs. VCE is not recommended in cats, even those weighing >9 lb (4 kg), because of gastric retention of the capsule. The sensitivity of VCE for detection of the source of GI bleeding in dogs is unknown but is likely less than that of traditional endoscopy; thus, VCE should only be used when more sensitive measures for detection of GI bleeding are unavailable.