Malabsorption in the horse associated with alimentary lymphosarcoma.

This research studied three horses suffering from malabsorption due to alimentary lymphosarcoma that affected their small intestines and related lymph nodes. Changes in the villous architecture and lowered disaccharidase resulted in impaired digestion, observed changes bore a resemblance to human’s alpha chain disease.

Study Aim and Methodology

• The aim of this research was to investigate the malabsorption suffered by three horses and identify its cause. The suspected underlying disease was alimentary lymphosarcoma affecting the small intestines and lymph nodes
• The researchers examined the horses’ condition, the symptoms they displayed and any significant changes in their physical characteristics such as changes in the villous architecture of their intestines.

Findings

• The profound changes in two of the horses’ small intestines, including diffuse cellular infiltration and degradation of villous architecture led the researchers to conclude that a reduction in available mucosal surface area and lowered or undetectable disaccharidase activities were contributing factors to the malabsorption.
• One of the horses, despite having a good appetite and no diarrhea, was unable to gain weight. This indicated a variation in the production and utilization of energy sources absorbed from the small and large intestines, suggesting that malabsorption was impacting its ability to process and utilize nutrients effectively.

Comparison to Human Disease

• The large number of plasma cells found in the infiltrate and the subsequent morphological changes in two of the horses bore a striking resemblance to features seen in alpha chain disease, a type of immunodeficiency disease that affects humans. However, no immunological studies were conducted on the horses to further explore this similarity.

Conclusion

• The research concludes that alimentary lymphosarcoma, primarily affecting the small intestine and associated lymph nodes, is likely the underlying cause of malabsorption in these horses. Changes in the intestinal architecture and significant decreases in the disaccharidase activities were likely contributors to the impaired digestive-absorptive processes, leading to malabsorption.