Gastroduodenal ulceration in small animals is a complex and important comorbidity that occurs when the physiological homeostasis of the gastrointestinal tract is disrupted secondary to administration of medications or the presence of local or systemic diseases. The aim of this article is to provide a comprehensive review of the veterinary literature regarding the pathophysiology, epidemiology, and risk factors associated with gastroduodenal ulceration in small animals. Pertinent concepts from the human literature will be integrated into the discussion. This article serves as an introduction to the second part of this series, which will review current evidence regarding the use of H2-receptor antagonists and proton pump inhibitors in small animals.
In the first part of this review, we discussed the pathophysiology and epidemiology of gastric acid secretion and the epidemiology of gastroduodenal ulceration in dogs and cats. In this section, we discuss the pharmacology and evidence-based clinical use of histamine-2 receptor antagonists and proton pump inhibitors.
Brachycephalic airway syndrome may predispose to gastroesophageal reflux (GER) because of the high negative intrathoracic pressures required to overcome conformational partial upper airway obstruction. To investigate this, 20 dogs presenting for elective correction of brachycephalic airway syndrome (cases) and 20 non-brachycephalic dogs (controls) undergoing other elective surgeries were prospectively enrolled. Dogs underwent a standardized anesthetic protocol, and esophageal pH was monitored. Signalment, body weight, historical gastrointestinal and respiratory disease, complete blood count, serum biochemical values, radiographic findings, and anesthetic and surgical time were compared between cases and controls, and dogs that did and did not have basic (pH > 7.5), acidic (pH < 4), or any GER. Controls had higher mean esophageal pH (6.3) compared to cases (5.6, P = .019), but there was no difference in % with GER (cases 60%, controls 40%, P = .34). When all dogs were evaluated, dogs with GER had increased creatinine (P = .01), % positive for esophageal fluid on radiographs (P = .05), and body weight (P = .04) compared to those without GER. GER was common in both cases and controls, and cases had lower esophageal pH; however, greater numbers are required to determine if a true difference exists in % GER.
The use of cytotoxic drugs to treat neoplastic conditions is increasing in veterinary practices. Many agents have the potential to be genotoxic and evidence of exposure to cytotoxic drugs has been found in healthcare workers handling these pharmaceuticals. To date, limited contamination evaluations have been performed in veterinary practices. Evaluation for carboplatin contamination was performed at a veterinary teaching hospital involving twelve areas in the dispensary and treatment room. Detectable levels of platinum were found on the surface of the biological safety cabinet where drugs are transferred from vial to administration device. Results indicate contamination did occur and care must be taken during all phases of cytotoxic drug preparation and administration; precautionary procedures must be in place to limit the spread of surface contamination and personnel exposure.
Dilated cardiomyopathy (DCM) is the most common myocardial disorder of dogs, typically affecting large and giant breeds. The purpose of this study was to describe the clinical features of DCM in standard schnauzers. Medical records for 15 standard schnauzers diagnosed with DCM were reviewed. The median age at diagnosis of DCM was 1.6 yr, with all dogs developing left-sided congestive heart failure (CHF). The median age of onset of CHF was 1.6 yr, and was significantly shorter in males (1.5 yr) than for females (2.35 yr). The median survival time after diagnosis of CHF was 22 days, and was shorter in males (13 days) than females (62 days). The occurrence of early onset DCM in multiple closely related standard schnauzers suggests a familial predisposition in this breed. Pedigree analysis confirmed common ancestry for all DCM affected dogs with a most likely autosomal recessive mode of inheritance.
Transcondylar screw fixation was performed using a minimally invasive percutaneous technique on three dogs (four elbows) diagnosed with incomplete ossification of the humeral condyle. The technique was performed using an aiming device in all four elbow joints and assisted by intraoperative fluoroscopy in one. All screws were successfully placed on first attempt and no elbow joint required repositioning of the transcondylar screw. On immediate postoperative radiographs, median transcondylar screw angulation was 2.9° and median percentage of screw eccentricity relative to the theoretical center of the humeral condyle was 14%. No short-term postoperative complications (<1 mo) were observed. The surgical technique described is a feasible option for surgical management of incomplete ossification of the humeral condyle in dogs that allowed accurate transcondylar screw placement and orientation.
This case report describes the use of two new concepts in the diagnosis and treatment of metastatic osteosarcoma (OSA) in one dog. The dog was initially presented for positron emission tomography and computed tomography (PET/CT) as full-body staging following amputation and adjuvant chemotherapy for treatment of OSA of the proximal tibia. The initial PET/CT did not show evidence of metastatic disease. Six mo after OSA, diagnosis pulmonary metastatic nodules were identified and oral toceranib phosphate was initiated. Twelve mo postdiagnosis the dog developed neck pain and non-ambulatory tetraparesis and was diagnosed with a C7 vertebral metastatic lesion based on magnetic resonance imaging. A second PET/CT was performed to screen for further metastatic lesions, and a nodule within the right ischium was identified. The C7 and ischial lesions were treated with stereotactic radiation therapy (SRT). Sixteen mo postdiagnosis, a third PET/CT was performed due to increasing size of the pulmonary nodules and a right-sided liver metastasis was detected. The liver mass was treated with SRT. The PET/CT scans facilitated identification of gross metastatic lesions that were subsequently treated with SRT, which resulted in clinical improvement of the dog's neurological signs.
A 7 yr old female spayed Yorkshire terrier was referred to the author's institute for a 5 mo history of recurrent cervical spinal pain. Neurologic examination did not reveal any deficits. Hematologic and serum analyses were within normal limits. Thoracic radiographs that incorporated the cervical spine did not show structural abnormalities. Magnetic resonance imaging of the cervical spine demonstrated a contrast enhancing, intradural extramedullary lesion at the level of the C2 vertebra. Hemilaminectomy was performed, during which a long, narrow nematode was visualized upon opening of the dura mater. The parasite was alive when removed during surgery, and the dog recovered with complete resolution of symptoms. The parasite was submitted and confirmed as a male adult Dirofilaria immitis. This is a novel case of an intradural D. immitis infection in the dog with a magnetic resonance imaging description of spinal D. immitis.