Fig. 3.

Histological findings in PSC. Concentric periductal fibrosis (“onion-skin”, indicated by arrows) with oedema and inflammatory portal cell infiltrate (Giemsa stain). The biopsy was performed on a 19-year-old man with newly diagnosed ulcerative colitis, markedly elevated cholestatic serum markers, and no cholangiographic changes. Five years later cholangiography showed typical findings of PSC