Concurrent systemic AA amyloidosis can discriminate primary sclerosing cholangitis from IgG4-associated cholangitis

Figure 1 Endoscopic retrograde cholangiopancreatography revealed multiple strictures of the hilar and intrahepatic bile ducts, with a “pruned-tree” appearance, accompanied by dilatation of the distal bile ducts.

Figure 2 Histology of the salivary glands and the sto-mach by hematoxylin and eosin stain (200 ×). Amorphous eosinophilic materials in the subglandular and stroma of the salivary glands (A) and submucosal stroma of the stomach (B) were demonstrated. They were found to be Congo-red-positive. Immunohistochemical staining with anti-human amyloid A antibody (200 ×) confirmed a positive AA stain in the salivary glands (C) and stomach (D).

Figure 3 Histology of the liver by hematoxylin and eosin stain. An increase in lymphoneutrophilic infiltrates in the portal tracts, interface hepatitis with ductular proliferation, cholate stasis (400 ×, A), and damaged interlobular bile ducts with collagenous periductal thickening (200 ×, B) were revealed. Amyloid deposition in the vessel walls of the portal tracts was also apparent in immunohistochemical staining (200 ×, C).

Figure 4 Serum amyloid A1 genotyping by polymerase chain reaction-restriction fragment length polymorphism analysis (2% agarose gel electrophoresis). Arrow (250 bp), arrow head (269 bp) and small arrow head (296 bp) correspond to serum amyloid A1 allele 1.5, 1.3 and 1.1, respectively. Lane 1: 1.5/1.5 homozygosity (our patient); Lane 2: 1.1/1.5 heterozygosity (control patient); Lane 3: 1.3/1.5 heterozygosity (another control patient).