Background Among patients with idiopathic inflammatory myopathy (IIM), not a few cases are associated with a variable degree of liver dysfunction1,2.. Not only aspartate aminotransferase (AST) as a myogenic enzyme, but also other hepatogenic enzymes, such as alanine aminotransferase (ALT), alkaline phosphatase (ALP), γ-glutamyl transpeptidase (γ-GTP), can rise in serum of the patients.
Objectives To investigate the clinical characteristics and hepatic histopathological findings in IIM.
Methods We retrospectively extracted 13 adult patients who was diagnosed as IIM in our hospital and underwent liver biopsy during the period of 2007 to 2014. We evaluated the clinical, serum, and hepatic histopathological aspects.
Results The case group comprised eight patients of polymyositis (PM) and five dermatomyositis (DMy). Mean age of the patients (three men and ten women) was 55.5 (24-76) years. The mean serum creatine kinase (CPK) level was 2352 (229-7515) IU/l, and the mean serum AST, ALT, ALP, and γ-GTP levels were 184.2 (42-857) IU/l, 142.3 (32-614) IU/l, 314.8 (114-601) IU/l, and 71.9 (15-250) IU/l, respectively. The histopathological findings in liver showed: two with autoimmune hepatitis (AIH) and two with primary biliary cirrhosis (PBC). All the four cases were polymyositis patients. In two out of five DMy, hepatocyte ballooning, ceroid-laden macrophage and acidophilic body were detected, but lymphocyte infiltration was very few. Another one of DMy was diagnosed non-alcoholic steatohepatitis (NASH) that also showed the hepatocyte ballooning. In addition, serum ferritin levels of these three cases were high (about 1373-1563 ng/ml) and CPK levels were relatively low (226-415 IU/l). Remaining six cases only showed non-specific mild liver damage. None of all 13 cases show normal liver histology.
Conclusions This study suggested that liver inflammation occer with high frequency in IIM, but the property may differ between PM and DMy.
Matsumoto T, Kobayashi S, Shimizu H, Nakajima M, Watanabe S, Kitami N, et al. The liver in collagen diseases: pathologic study of 160 cases with particular reference to hepatic arteries, primary biliary cirrhosis, autoimmune hepatitis and nodular regenerative hyperplasia of the liver. Liver 2000; 20: 366-373
Takahashi A, Abe K, Yokokawa J, Iwadate H, Kobayashi H, Watanabe H, et al. Clinical features of liver dysfunction in collagen diseases. Hepatology Research 2010; 40: 1092-1097
Acknowledgements The authors grateful to staffs of department of rheumatology, hepatology, pathology of the Jikei University Hospital.
Disclosure of Interest None declared