Histologic grading schemes for canine inflammatory conditions are sparse, and in the case of the canine pancreas, have not been previously described. In a previous study, we determined that histologic lesions of the exocrine pancreas occurred much more frequently than gross lesions. The intention of the current study was to develop a histologic grading scheme for nonneoplastic lesions following extensive assessment of the exocrine pancreas from dogs presented for necropsy examination. The parameters of the proposed scheme include neutrophilic inflammation, lymphocytic inflammation, pancreatic necrosis, pancreatic fat necrosis, edema, fibrosis, atrophy, and hyperplastic nodules. In this case series, the most common lesion was pancreatic hyperplastic nodules (80.2%), followed by lymphocytic inflammation (52.5%), fibrosis (49.5%), atrophy (46.5%), neutrophilic inflammation (31.7%), pancreatic fat necrosis (25.7%), pancreatic necrosis (16.8%), and edema (9.9%). Only 8 of the 101 animals had no evidence of any of the lesions in any of the sections examined. Fibrosis, atrophy, and/or lymphocytic infiltration most commonly accompanied nodules. Neutrophilic inflammation, when present, was often associated with necrosis (pancreatic necrosis, pancreatic fat necrosis, or both) and occasionally with hyperplastic nodules. The utilization of a grading scheme for exocrine pancreatic lesions will be useful in advancing the classification of exocrine pancreatic disease in the dog, which may lead to multicenter studies of exocrine pancreatic disorders in the dog and in other species.

Few studies of the prevalence of histologic lesions of the exocrine pancreas in dogs have been reported, and none of them systematically evaluate the localization of these lesions. The purpose of this study was to describe the anatomic localization of pancreatic inflammation, necrosis, and fibrosis in dogs presented for postmortem examination. Seventy-three pancreata from dogs presented for postmortem examination were evaluated and investigated for the presence of suppurative inflammation (SI), pancreatic necrosis (PN), and lymphocytic inflammation (LI). Sections that showed evidence of SI, PN, or LI also were evaluated for pancreatic fibrosis (F). The tendency for a preferred localization for SI, PN, and LI was evaluated by chi-square analysis. A total of 47 pancreata with histologic evidence of pancreatitis (SI, PN, or LI; F alone was not considered evidence of pancreatitis) were identified. Twenty-four (51.1%) had SI, 23 (48.9%) had PN, and 34 (72.3%) had LI. Of the 47 dogs with SI, PN, or LI, 28 (59.6%) had F. The distribution of SI, PN, and LI between the right and the left limb of the pancreas and among the 5 anatomic regions was random, based on a goodness-of-fit test. We conclude that pancreatic inflammation tends to occur in discrete areas within the pancreas rather than diffusely throughout the whole organ. These findings suggest that a single biopsy is insufficient to exclude subclinical pancreatitis and that there is no preferred site for pancreatic biopsy collection unless gross lesions are apparent.

Few studies of the prevalence of histologic lesions of the exocrine pancreas in dogs have been reported, and none of them systematically evaluate the localization of these lesions. The purpose of this study was to describe the anatomic localization of pancreatic inflammation, necrosis, and fibrosis in dogs presented for postmortem examination. Seventy-three pancreata from dogs presented for postmortem examination were evaluated and investigated for the presence of suppurative inflammation (SI), pancreatic necrosis (PN), and lymphocytic inflammation (LI). Sections that showed evidence of SI, PN, or LI also were evaluated for pancreatic fibrosis (F). The tendency for a preferred localization for SI, PN, and LI was evaluated by chi-square analysis. A total of 47 pancreata with histologic evidence of pancreatitis (SI, PN, or LI; F alone was not considered evidence of pancreatitis) were identified. Twenty-four (51.1%) had SI, 23 (48.9%) had PN, and 34 (72.3%) had LI. Of the 47 dogs with SI, PN, or LI, 28 (59.6%) had F. The distribution of SI, PN, and LI between the right and the left limb of the pancreas and among the 5 anatomic regions was random, based on a goodness-of-fit test. We conclude that pancreatic inflammation tends to occur in discrete areas within the pancreas rather than diffusely throughout the whole organ. These findings suggest that a single biopsy is insufficient to exclude subclinical pancreatitis and that there is no preferred site for pancreatic biopsy collection unless gross lesions are apparent.

The cutoff cPSL value used in this study may be useful for diagnosing pancreatitis in dogs with a lack of histologic lesions consistent with pancreatitis and for which pancreatitis is not considered a major differential diagnosis.

The purpose of this study was to determine the prevalence of pancreatic nodular hyperplasia (NH) and its relation to age in the dog. A total of 101 dogs were enrolled. The pancreas was evaluated by histology and hyperplastic lesions were detected and scored. Age was recorded from the medical records. Correlation of age with inflammation and presence of hyperplastic lesions was evaluated. Of the 101 dogs, 81 (80.2%) had evidence of NH. Twenty-five of the 101 dogs did not have evidence of pancreatic inflammation, necrosis, and/or fibrosis, 17 (68.0%) of which had evidence of NH. Mean +/- SD age in dogs with NH was significantly higher compared with dogs without NH (9.5 +/- 3.4 years versus 3.4 +/- 3.3; P-value < 0.0001). We conclude that NH is a common pathologic lesion in dogs and shows a positive correlation with age regardless of the presence or absence of pancreatic inflammation, necrosis, or fibrosis.