Page 804 - Cote clinical veterinary advisor dogs and cats 4th

Gastric Ulcers 381

PHYSICAL EXAM FINDINGS if severe or associated with gastric perforation Advanced or Confirmatory Testing
Generally nonspecific and may be normal: and peritonitis. • Serum gastrin levels may help diagnose
VetBooks.ir • ± Evidence of anemia (e.g., pale mucous Differential Diagnosis receiving acid-suppressing drugs at the time Diseases and Disorders
gastrinoma, but the animal should not be
• ± Pain on abdominal palpation or pain
manifested as a praying position
of testing.
• Acute vomiting (p. 1293)
membranes, tachycardia)
○ Coagulopathies or platelet disorders
free gas is seen in the abdomen on imaging,
• ± Melena on rectal exam • Hematemesis • If gastric perforation is suspected and no
• Signs of shock (p. 911) possible with severe (decreased number or function) abdominocentesis (p. 1056) is indicated.
bleeding or gastric perforation ○ Ingested blood (nasopharyngeal, oral, Ultrasound can guide sampling of even
• Evidence of septic peritonitis (p. 779) pos- esophageal, or pulmonary bleeding) small amounts of free fluid sufficient for
sible with gastric perforation ○ Acute hemorrhagic diarrhea syndrome cytological evaluation. Cytological evaluation
○ Any cause of severe GI erosion may show only neutrophilic inflammation
Etiology and Pathophysiology • Melena (p. 644) with no evident cause in up to 44% of
• See causes of gastrointestinal (GI) ulceration • Abdominal pain (p. 21) cases. Peritoneal lavage may be needed to
(p. 1225). obtain samples if fluid accumulation is
• Primary gastroduodenal diseases (e.g., toxins Initial Database scant.
or foreign bodies, chronic gastritis, inflam- • Rectal exam to assess presence of melena; • Gastroscopy (p. 1098): preferred for confir-
matory bowel disease, neoplasia [lymphoma, not always found mation of gastric ulcer and tissue sampling;
adenocarcinoma, leiomyosarcoma, GI • CBC, serum biochemistry profile, urinalysis: can identify or confirm perforation and need
stromal tumor, gastrinoma], pyloric outflow important to identify underlying cause of for immediate surgical intervention
obstruction) gastric ulceration and especially important ○ A solitary ulcer in an otherwise normal
• Gastric hyperacidity disorders (e.g., gastri- if hematemesis or melena is present stomach should raise suspicion of gastric
nomas, hypergastrinemia due to drugs, mast ○ CBC may show anemia (variably regen- neoplasia, especially if the edges and sur-
cell tumors) erative if acute, depending on the time rounding mucosa are thickened.
• Drug-induced ulcers (e.g., COX inhibitors, between onset of bleeding and time of ○ NSAID-induced ulcers can be solitary, but
other NSAIDs, corticosteroids) testing; nonregenerative in the setting of the surrounding mucosa is usually not
• Exercise-induced ulcers theorized to occur underlying chronic disease; in dogs with normal because of generalized mucosal
from prolonged hyperthermia during exercise iron deficiency from chronic blood loss disease (gastritis and other erosions are
that increases gastric paracellular permeability may be microcytic, hypochromic, and common).
to acid, resulting in mucosal damage. either regenerative or nonregenerative), ○ Multiple, diffuse, small ulcers can be seen
• Other metabolic, endocrine, or systemic causes neutrophilia (± left shift if associated with NSAIDs, uremia, liver disease, high-
(e.g., pancreatitis, disseminated intravascular with perforation), hypoproteinemia, or grade mast cell tumor, and gastrinoma.
coagulation, hypoadrenocorticism, chronic mild thrombocytopenia (rarely less than ○ Biopsies should be obtained from the ulcer
kidney disease, liver failure, hypovolemic/ 75,000/mcL) or thrombocytosis. periphery to avoid perforation. Repeated
septic shock, neurologic diseases [especially ○ Serum biochemistry profile may or may biopsies from the same site may improve
intervertebral disc disease]) not show a high blood urea nitrogen the likelihood of identifying neoplasia.
• The causes of ulceration are similar to those (BUN)/creatinine ratio or identify condi- In some cases, endoscopic biopsies are
of gastritis and erosion, but for unknown tions associated with ulcers (e.g., kidney inadequate for diagnosis (neoplastic tissue
reasons, the reparative mechanisms of the disease). is deeper than superficial mucosal tissues
mucosa are overwhelmed, resulting in deep ○ Urinalysis: essential for differentiat- sampled with endoscopic biopsies), and
indolent lesions. ing BUN elevation due to kidney laparotomy is required for full-thickness
• Ulcer healing starts as necrotic mucosa disease (urine specific gravity [USG] = biopsies.
sloughs and granulation tissue fills the 1.008-1.020) from BUN elevation due
ulcer. Mucus and bicarbonate are secreted to prerenal causes (USG > 1.035) or GI TREATMENT
by the neighboring mucosa to protect bleeding (any USG).
the ulcer. Granulation tissue eventually • Fecal occult blood test has limited utility. Treatment Overview
organizes, a connective tissue bed devel- ○ O-tolidine–based tests are significantly Goals are to remove the primary cause and
ops, and epithelial tissues slide across the more specific (0/108 false-positive results promote healing. For animals with massive
surface to re-epithelialize it. Glandular in healthy dogs) than guaiac-based tests bleed or perforation, stabilization must be
structures are the last to repopulate the (64/108 false-positive results in same the first priority.
denuded area. dogs).
• Reduced gastric acid secretion facilitates • Imaging studies Acute General Treatment
healing by decreasing tissue damage from ○ Plain radiographs cannot confirm gastric Supportive care:
acid and by decreasing further damage from ulceration. If perforation has occurred, • Intravenous fluids, antibiotics, antiemetics,
pepsin, which is less active at higher pH. loss of detail (suggesting peritonitis or and opioid analgesics may be required for
free abdominal fluid) or free peritoneal the patient with severe vomiting that has
DIAGNOSIS gas may be present. resulted in dehydration and electrolyte
○ Contrast radiographs (p. 1172) may disturbances.
Diagnostic Overview identify a mucosal filling defect. • Blood transfusion for the patient with severe
Gastric ulceration should be suspected in ○ Ultrasonography may show focal gastric anemia as a result of massive bleeding
patients with any signs of GI disturbance that wall thickening, loss of normal layering, Surgery:
persist or worsen beyond the degree expected for a wall defect or crater, fluid accumulation • Surgical resection is indicated when the ulcer
the primary diagnosis. There may be a history in the stomach, and diminished gastric appears deeply penetrating (volcano crater
of receiving ulcerogenic medications or other motility. In animals with perforation, appearance), is bleeding continuously, has
known risk factors for ulcer. In many mild there may be evidence of free abdominal perforated, or is large and fails to heal.
cases, diagnosis is only presumptive (response fluid. • Surgical exploration may identify the cause
to antiulcer medications); a definitive diagnosis ○ CT scan may be more sensitive than (neoplasia) and allow resection of the mass/
requires endoscopy or laparotomy, particularly radiographs or ultrasonography. ulcer.

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