Dr. Bari Spielman
Gastrinomas are malignant tumors of the pancreas that often become progressively worse and result in death of the patient. These tumors secrete the hormone gastrin that stimulates stomach acid secretion and in turn, causes gastrointestinal ulceration. In human medicine gastrinomas are referred to as the Zollinger-Ellison syndrome. These tumors commonly metastasize, or spread to other organs, early in the disease process. The ingestion of certain drugs and medications may cause either gastrointestinal ulceration or signs similar to individuals with ulceration, including vomiting and lack of appetite.
Gastrinomas are fairly uncommon in veterinary medicine, although have been reported in both dogs and cats. Signs can be extremely variable from patient to patient. Some patients may have no clinical signs, while others may be in immediate need of intensive support and hospitalization, to include very close monitoring and even blood transfusions.
Gastrointestinal ulceration has many other causes besides gastrinomas. It is important to realize that while some cases of ulceration are clear cut when reviewing the history, physical examination and diagnostic findings, it is sometimes more difficult to identify a gastrinoma as the primary cause.
Many diseases/disorders cause similar clinical signs to patients with gastrinomas.
Metabolic disorders such as kidney failure, liver disease, hypoadrenocorticism, hyperthyroidism in cats are often associated with vomiting and/or gastrointestinal ulceration and may need to be differentiated from gastrinomas.
Stress, pain, fear and/or major medical illness to include shock, low blood pressure, trauma, and major surgery can all be associated with vomiting and/or gastrointestinal ulceration.
Dietary indiscretion, or the ingestion of foreign bodies or inappropriate/excessive food items, is a common disorder seen in both cats and dogs. Vomiting, diarrhea and gastric ulceration are commonly seen.
Pancreatitis is an inflammation of the pancreas, and in certain cases, can be life-threatening. The most common clinical signs seen with pancreatitis are vomiting and inappetence. Pancreatitis is a common cause of GI ulceration.
Intestinal obstruction/blockage secondary to foreign bodies, tumors or an intussusception, which is the telescoping of one part of the bowel into itself, must be differentiated from and/or can cause GI ulceration.
Mast cell tumors are growths that occur anywhere in or on the body and secrete substances that can cause gastrointestinal ulceration.
Infiltrative diseases of the gastrointestinal tract, including inflammatory bowel disease and lymphosarcoma (a type of cancer) must be ruled out. Infiltrative diseases are microscopic diseases that penetrate and spread throughout the body.
Hemorrhagic gastroenteritis (HGE) is a syndrome seen in dogs that has no known cause. These animals often experience vomiting (with or without blood) and bloody diarrhea. HGE is most often seen in urban settings in small breed dogs.
Clotting disorders, such as thrombocytopenia (decreased platelet count) or warfarin toxicity (rat poison), may present with bloody diarrhea or vomiting.
Neurologic disorders, especially of the vestibular center that deals with balance and coordination, often causes vomiting.
Certain toxins, such as lead, can cause severe gastrointestinal signs and ulceration.