Lymphoplasmacytic Enteritis

Lymphoplasmacytic enteritis describes a pattern of persistent inflammation in the small intestine, where particular types of immune cells—lymphocytes and plasma cells—gather in numbers higher than usually seen in healthy tissue. This inflammation can interfere with how the gut absorbs nutrients and how comfortably it moves food through. It sits within a broader group of conditions sometimes called inflammatory bowel disease, though that term is used differently across contexts. Owners often arrive at this page because their dog or cat has been experiencing ongoing digestive signs—loose stools, weight loss despite eating, occasional vomiting, or a coat that has lost condition. These signs tend to build gradually rather than appearing suddenly, and they may come and go over weeks or months. The condition is confirmed through biopsy, not through symptoms alone, so many owners are seeking to understand what the diagnosis means and what has been found in their pet's tissue. This page explores the signals that can appear in affected animals, the mechanisms that may drive the inflammation, the investigations used to reach and refine the diagnosis, and the range of approaches—dietary, medical, and supportive—that may be considered in managing the condition over time.