Pathology of the spleen in primary biliary cirrhosis: an autopsy study

Pathologic changes of the spleen in primary biliary cirrhosis (PBC) were studied using autopsy cases. By analysis of the data complied in the Annual Registry of Autopsies of Japan (1977-92), it was found that the splenic weight of 184 cases of PBC (450 +/- 224 g) was significantly heavier than that of 41 control autopsy cases of non-biliary liver cirrhosis from the School of Medicine, Kanazawa University (341 +/- 189 g), and also of 210 control cases filed in the Annual Registry of Autopsies of Japan (1982; 334 +/- 174 g). Among the cases of PBC, the splenic weight was positively correlated with the liver weight. There was no significant difference in the splenic weight between the cases belonging to histologic stages 1-3 and those of stage 4. Fibrosis extending from the splenic trabecula, proliferation and dilatation of the splenic sinus, and congestion in the red pulp, all being compatible with chronic splenic congestion, were similarly observed in the spleen in PBC as well as in other non-biliary cirrhotic cases. The present study indicates that the PBC patients present splenomegaly in the non-cirrhotic histologic stage and splenomegaly persists thereafter. However, the histopathologic changes of the spleen peculiar to PBC were not specified in this autopsy study. Prolonged portal hypertension and other mechanisms, possibly related to immune disarrangement, may be responsible for the prominent splenomegaly in PBC.