A Comparison of Liver Biopsy Techniques in Dogs
Background: The liver biopsy technique in dogs that consistently provides samples adequate for accurate histopathologic interpretation and the variability of histopathology among lobes is unknown.
Hypothesis: Liver biopsy specimens obtained via punch, cup biopsy, and 14 gauge needle biopsy would result in similar histopathologic diagnoses to those found on deeply sectioned samples of liver obtained at necropsy and that discordant results would not differ between lobes.
Animals: Seventy dogs undergoing necropsy.
Methods: Liver specimens were obtained from the left lateral liver lobe with an 8 mm punch, a cup, and a 14 gauge needle. Two larger tissue samples were then collected near the center of the left lateral lobe and used as a histologic standard for comparison. Samples were also obtained from all remaining lobes. Histopathologic features and numbers of portal triads in each sample were compared.
Results: The mean number of portal triads were 2.9 in needle biopsies, 3.4 in cup biopsies, 12 in punch biopsies, and 30.7 in the necropsy samples. Sixty-six percent of needle biopsies, 60% of laparoscopic cup samples, and 69% of punch samples were in agreement with the necropsy samples, differences that were not significantly different. The corresponding kappa coefficient were 0.59 for needle biopsies, 0.52 for cup biopsies, and 0.62 for punch biopsies. Discordant results did not differ between the liver lobes.
Conclusions and Clinical Relevance: A single biopsy using any of the tested techniques is insufficient for reliable diagnosis of liver disease in the dog. Multiple biopsies from 2 lobes is recommended.