Malabsorption in dogs refers to the impaired absorption of nutrients, stemming from disruptions in either digestion, absorption, or both processes. While interference with food digestion is often linked to a deficiency in pancreatic enzymes (exocrine pancreatic insufficiency), most absorption failures are attributed to diseases affecting the small intestine.
The primary symptoms of malabsorption arise from the body’s inability to adequately take up nutrients, leading to their loss in feces. These typically manifest as chronic diarrhea, weight loss, and changes in appetite, which can range from a complete loss to excessive eating. However, it’s important to note that diarrhea may not always be present, even in severe cases. Significant weight loss can occur despite a healthy appetite, sometimes accompanied by the consumption of feces or non-food items. Unless the condition involves severe inflammation or cancer, dogs with malabsorption generally appear otherwise healthy. Other nonspecific signs might include dehydration, anemia, the presence of dark blood in stools, or fluid retention. A veterinarian may also detect thickened intestinal loops or enlarged abdominal lymph nodes during an examination.
Diagnosing malabsorption can be challenging, as chronic diarrhea and weight loss are common indicators for a variety of diseases. Consequently, reaching an accurate diagnosis might require multiple veterinary visits. A comprehensive examination is crucial for dogs exhibiting malabsorption signs to rule out underlying generalized or metabolic conditions. Specific tests can help identify if the symptoms are related to conditions like inflammatory bowel disease, liver disease, or parasitic infections. The dog’s medical history plays a significant role, potentially pointing towards food allergies, the ingestion of non-food items, or other sensitivities. While weight loss can signify malabsorption or protein-losing conditions, it can also be a result of appetite loss, vomiting, or non-digestive ailments. Certain characteristics can differentiate small intestinal diarrhea from large intestinal diarrhea. If large intestinal disease is suspected, a biopsy of the intestinal lining may be performed. However, if weight loss or large volumes of feces accompany these signs, the small intestine is likely affected as well. Initial diagnostic steps typically involve blood, urine, and fecal tests, along with X-rays and an abdominal ultrasound. Specialized blood tests and tissue biopsies may also be required.
Treatment for malabsorption encompasses dietary adjustments, managing complications, and addressing the underlying cause if identifiable. For malabsorption caused by exocrine pancreatic insufficiency, treatment involves a specialized low-fiber diet with moderate fat content, highly digestible carbohydrates, and high-quality protein. Supplementation with pancreatic extracts to replace missing enzymes is also essential. If the dog’s response to pancreatic enzyme replacement therapy is suboptimal, small intestinal bacterial overgrowth might be suspected. In such cases, a course of oral antibiotics for approximately one month may be prescribed to mitigate bacterial overgrowth. The effectiveness of treating small intestinal disease hinges on the specific nature of the disorder; however, if a definitive diagnosis cannot be made, treatments may be initiated on a trial basis.
Dietary modification is a cornerstone in managing small intestinal diseases. Your veterinarian might suggest an exclusion diet, featuring a single protein source to which your dog has not been previously exposed, as a diagnostic measure for suspected dietary sensitivities. It is imperative to strictly adhere to the prescribed special diet and medications. Owners may be tempted to offer “special treats” not included in the diet, despite instructions to the contrary. Deviating from the prescribed diet can impede diagnosis and delay necessary treatment. During this period, owners can offer non-food rewards such as petting, a new blanket, a suitable toy, or simply extended periods of attention, which are often the most appreciated by the pet.
The prognosis for dogs experiencing malabsorption is generally favorable if the cause is straightforward. For instance, approximately 85% of dogs with exocrine pancreatic insufficiency show a positive response to treatment with pancreatic enzymes. However, the outlook is less positive for dogs suffering from severe small intestinal disease, cancer, fluid retention due to low protein levels, significant weight loss, low vitamin B12 levels, or a lack of appetite.
