Malabsorption in Dogs
Dr. Bari Spielman
Malabsorption refers to deficiency in the absorption of one or more nutrients in the gastrointestinal tract as a result of disruption of the normal process of digestion and absorption. Digestion and absorption of nutrients occur in three sequential phases: intraluminal digestion, mucosal digestion and absorption, and delivery of nutrients to the circulation. Many diseases cause chronic malabsorption by interfering with these processes. Some of these include: Inflammatory bowel disease, a microscopic infiltration of the intestinal wall with inflammatory cells. The cause is unknown, although it is suspected to have an immune basis.
Intestinal neoplasia, such as lymphosarcoma, adenocarcinoma and leiomyosarcoma
Intestinal bacterial overgrowth, which is characterized by an overgrowth of normal intestinal flora (bacteria) usually secondary to various gastrointestinal diseases, but occasionally as a primary entity.
Infectious enteropathies, such as bacterial, viral, fungal, parasitic, rickettsial
Short bowel syndrome, which is created after a large portion of the intestinal tract is resected for any number of reasons. The remaining bowel is incapable of functioning normally, and malabsorption often develops.
Lymphangiectasia, which is an obstructive (blockage) disorder involving the lymphatic system of the gastrointestinal tract. This results in protein being lost through the gastrointestinal tract and causes profound hypoproteinemia or low protein levels.
Villous atrophy (wheat-sensitive enteropathy)
What to Watch For
Depending on the underlying cause, different breeds and ages are affected. There is a tremendous variation in spectrum and severity of signs.
Soft stool or watery diarrhea
Stools containing undigested food
Increased frequency of defecation and stool volume
Increased or decreased appetite
Borborygmus (noise coming from the gastrointestinal tract)
A thorough knowledge of history and clinical signs is very important and is most helpful in the diagnosis of malabsorption. The following diagnostic tests may also be necessary:
Complete blood count (CBC)
Fecal bacterial cultures
Abdominal radiographs (x-rays)
Radioimmunoassay of serum trypsinlike immunoreactivity (TLI), a blood test to rule out exocrine pancreatic insufficiency, a maldigestive disorder that often presents with similar signs
Folate and cobalamin (vitamin B12) levels, which are blood tests that assess for malabsorption and bacterial overgrowth
Endoscopic examination and biopsy
Treatment should be directed at the underlying cause, as different disorders require different therapy.
Pancreatic enzyme replacement
Administer prescribed diet and medication. Follow patient closely for resolution of symptoms, especially diarrhea and body weight. If improvement is not appreciated over the first week or two, contact your veterinarian.
There is no preventative available for malabsorptive disorders.