Lacrimal gland and salivary gland lesions

Abstract

Tissue biopsies undertaken to diagnose IgG4-related dacryoadenitis and sialadenitis are of great diagnostic value. Not only do they provide one of the bases for the diagnosis, they also facilitate the differentiation of conditions such as malignant lymphoma. In IgG4-related dacryoadenitis and sialadenitis, as in other types of IgG4-related disease (IgG4-RD), both a marked lymphoplasmacytic infiltrate and fibrosis are characteristic histopathological findings. The plasma cell population within tissue is comprised of an overabundance of IgG4-positive cells, and the IgG4:total IgG ratio is typically in excess of 0.40. Numerous lymph follicles are also found within tissues. Storiform fibrosis and obliterative phlebitis, generally viewed as typical histopathological features of IgG4-RD, are perhaps less common in the salivary and lacrimal glands compared to autoimmune pancreatitis. Thus, some organ-to-organ variability in the pathological features of IgG4-RD is observed.