Lymphocytic Plasmacytic Enteritis in Dogs
Dr. Bari Spielman
The term lymphocytic plasmacytic enteritis (LPE) refers to the most common form of inflammatory bowel disease (IBD). It is characterized by a particular population of inflammatory cells – lymphocytes and plasma cells – that are microscopically over- represented, and that gather within the intestinal wall. Although a definitive cause has not been well established, LPE is felt to be associated with an abnormal immune response to environmental stimuli that when continued, creates a self-perpetuating inflammation resulting in the disease. Severe liver disease must be ruled out as a contributing cause of hypoproteinemia: Hepatitis (inflammation of the liver), cancer, and cirrhosis (end stage liver disease).
Signs associated with LPE vary greatly in type, severity, and frequency. In general, early in the disease process signs are often mild and intermittent, but they increase in severity and frequency over time. Some combination of vomiting, diarrhea, weight loss and appetite change are most often noted. Often there is an association with hypoproteinemia (low protein levels) caused by an excessive loss of protein into the gut. In animals that are hypoproteinemic, it is important to note that the initial step in the diagnosis is to exclude non-intestinal causes of hypoproteinemia, specifically related to the liver or kidneys. Many disorders must initially be considered when these individuals present.
Disorders other than primary gastrointestinal diseases that cause hypoproteinemia:
Protein losing kidney disorders need to be considered in hypoproteinemic patients: Glomerulonephritis (inflammation of a part of the kidney) or amyloidosis, which is the deposition or collection of a type of protein in organs and tissues that compromise their normal function.
Blood loss for any reason will decrease the protein level.
Inadequate protein intake will contribute to hypoproteinemia.
Other infiltrative inflammatory bowel conditions:
Eosinophilic enteritis, granulomatous enteritis
Infectious diseases such as histoplasmosis. This is a fungal infection that affects many systems, including the gastrointestinal tract.
Intestinal parasitism has been associated with PLE, especially in young pups that are anemic as well (Roundworms, hookworms, whipworms, coccidia, and giardia).
Bacterial infections (Giardia, Salmonella, Campylobacter).
Exocrine pancreatic insufficiency (EPI) is a disorder where chronic diarrhea and weight loss develop secondary to inadequate production of digestive enzymes.
Intestinal lymphangiectasia, which is blockage of the lymphatics of the gastrointestinal tract.
Cancer of any sort must be ruled out. Lymphosarcoma is a malignant cancer that most often presents in the form of a microscopic infiltration into the bowel, however may form mass lesions.
An intussusception, or telescoping of part of the bowel into an adjacent segment of bowel, especially chronic, may cause similar signs.
Chronic foreign bodies of the intestinal tract are often associated with a number of gastrointestinal signs such as diarrhea, vomiting, and weight loss.
Ulcerative gastroenteritis – interruptions in the lining of the gastrointestinal tract – must be considered. It may be secondary to inflammation, drug administration, cancer or foreign bodies.
Small intestinal bacterial overgrowth is characterized by an overgrowth of normal intestinal flora (bacteria) usually secondary to various gastrointestinal diseases, but occasionally as a primary entity
Hemorrhagic gastroenteritis (HGE) is a dramatic, potentially fatal disorder with no one known cause. It has a predilection for small breed dogs. HGE is characterized by the sudden onset of profuse bloody diarrhea and occasional vomiting.
Food allergies, gluten-induced enteropathies, which are sensitivity to a component of wheat and other grains.