Lesions of subclinical doberman hepatitis

This investigation describes histologic lesions in the livers of 18 Doberma n Pinschers suffering from subclinical doberman hepatitis (DH). The dogs' a ges ranged from 2.5 to 7 years; 15 were females and 3 were males. At the ti me of liver biopsy, the dogs had no clinical signs of liver disease, althou gh serum alanine aminotransferase (ALT) values had been elevated in two sam ples in successive months. In the histologic examination, all biopsies reve aled parenchymal and portal mononuclear inflammation. In the parenchyma, th e inflammation was diffuse, with multifocal clusters of inflammatory cells. The periportal reaction was usually mild to moderate. Bridging necrosis (3 /18) and bile duct proliferation (2/18) were rare. Excessive copper was det ected by rubeinic acid stain in every specimen. Postmortem liver samples we re obtained from nine dogs 3.5-65 months after the initial biopsy specimen; five of these dogs had been euthanatized for reasons other than DH, and li ver specimens revealed piecemeal necrosis (5/5), bridging necrosis (3/5), a nd bile duct proliferation (2/5). Four of them had been euthanatized becaus e of DH. Liver lesions of these dogs were typical for chronic active hepati tis, with bridging and piecemeal necrosis (4/4), portal expansion (4/4), bi le duct proliferation (4/4), and fibrosis (4/4). A scoring system was used to evaluate changes numerically from biopsy to postmortem samples. Lesions in all dogs had progressed. The most important histologic changes were expa nsion of portal areas (P = 0.008), increased periportal and bridging necros is (P = 0.008), increased fibrosis (P = 0.016), and proliferation of the bi le ducts (P = 0.063).