Sjögren syndrome-related plasma cell disorder and multifocal nodular AL amyloidosis: clinical picture and pathological findings.

Localized nodular deposits of AL amyloid are seen in different tissues/organs; however, the pathogenesis of this form of amyloidosis remains unclear. Recently, Sjögren syndrome combined with localized nodular AL amyloidosis has been noted. Here, we report Sjögren syndrome cases showing multifocal nodular AL amyloidosis and the followed benign course. We investigated the clinical pictures and histopathological findings of three cases with both presence of Sjögren syndrome and localized nodular AL amyloidosis, paying a special attention to the distribution of amyloidoma. All three cases were middle-aged females. In two of three cases localized deposits of AL amyloid preceded Sjögren syndrome. Amyloidoma was detected in scalp, eyelid, cheek, larynx, trachea, lung and breast, and around these amyloid-deposited lesions infiltration of plasma cells was seen. Pulmonary amyloidosis was consistently accompanied with parenchymal cystic lesions, but this amyloidosis did not produce any significant respiratory symptoms. Some of large pulmonary amyloidomas showed cavity formation and subsequent shrinkage. In two cases amyloid deposition was found on gastric mucosa. Two cases received small doses of oral prednisone, with no further appearance of amyloidoma. Sjögren syndrome-related plasma cell disorder may be responsible for the formation of this unique multifocal nodular AL amyloidosis.