Histological examination of the resected omentum demonstrated both arteritis and more severe venulitis
, focal necrotizing vasculitis of the venules, and palisading granuloma (Figures 3(a) and 3(c)).
(5,6) Characteristics of these diseases include a high proportion of IgG4-positive plasma cells, predominantly T-lymphocytic infiltrate, storiform fibrosis, and venulitis
. (13) These features were not seen in our case.
Microscopic features include dense periductal lymphoplasmacytic inflammation, fibrosis and obliterative venulitis
. Other features may include arteritis and so called "granulocytic epithelial lesions" (granulocytic periductal and ductal inflammation with or without rupture and destruction of the ductal epithelium).
In addition, we saw involvement of the adventitial micro-vasculature, similar to the adventitial venulitis
described in a case of IgG4-related aortitis, (3) as well as involvement of several other organs.
Cutaneous necrotizing venulitis
. In: Waff K, Goldsmith LA, Katz SI, Gilchrest BA, Palter AS, Leffell DJ, eds.
. Dermatol Ther 2000; 13:400-408.
Histopathological investigation of AIP typically reveals dense periductal lymphoplasmacytic inflammation, periductal and parenchymal fibrosis, and obliterative venulitis
The dense, plasma cell-rich inflammation centered on the pancreatic ducts, along with venulitis
, can extend into the peripancreatic adipose tissue and create a clinical picture of a pseudotumor.
In this study, Yamashita et al (8) reported 3 patients with interstitial lymphoplasmacytic interstitial infiltrates associated with arteritis and venulitis
. One patient was asymptomatic, whereas 2 others reported dyspnea.
In brief, paraduodenal chronic pancreatitis is characterized by inflammatory, cystic, and fibrotic changes in the duodenal wall and the adjacent pancreatic tissue near the minor papilla, while autoimmune pancreatitis4 typically shows lymphoplasmacytic periductal infiltration, perilobular and sometimes diffuse cell-rich sclerosis, and venulitis
. (6) Moreover, in approximately 50% of the cases, the plasma cells stain for immunoglobulin G4 (IgG4), while the IgG4-negative cases show granulocytic epithelial lesions.