You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

TLI testing can help to detect subclinical exocrine pancreatic insufficiency (EPI) in dog breeds known to be predisposed to develop this condition, and histopathological studies in these cases have now shown that the underlying cause of pancreatic acinar atrophy is probably an immune-mediated disorder.

Two dog breeds have been described as being predisposed to develop pancreatic acinar atrophy - the German Shepherd dog and , in Finland, Rough-coated Collies. Genetic studies suggest the condition is due to a  recessive polygenic trait in these breeds. 

By screening apparently healthy dogs it  has been shown that repeated low trypsin-like immunoreactivity (TLI) (<5.0mg/L) precedes the development of acinar atrophy and subsequent exocrine pancreatic insufficiency.  On gross examination of the pancreas in these early cases pancreatic mass is reduced, and on histopathological examination T-lymphocyte infiltration is found in addition to normal and atrophied acinar tissue, suggesting that the underlying disease is probably immune-mediated. The predominant types of lymphocytes found infiltrating the pancreas were cytotoxic  CD8+  and CD4+ helper cells. Some dogs also had autoantibodies to acinar cell cytoplasm. It was found that subclinical EPI may be present for many months or even years (observed range 1-4 years) before clinical signs occur.

Reference

W. Wiberg "Immune-mediated lymphocytic pancreatitis in German Shepherd dogs and Rough-coated Collies" ESVIM Newsletter Vol 11 No 2 p12-14 (2001)

Updated October 2013