| Abstract: | A case of amyloidosis cutis nodularis atrophicans (ACNA) was reported. The characteristics of the amyloid deposit were examined using the unlabeled immunoperxoidase method (peroxidase-antiperoxidase method, so called PAP). The study revealed that the amyloid deposit contained A type protein AL, and the surrounding plasma cells contained λ and κ types of both immunoglobulin light chains and Bence Jones protein, with strong preference toward the λ type of each protein. These results suggest that, in ACNA, the plasma cells produce and secrete immunoglobulin light chains and/or Bence Jones protein, and that the protein degenerates into protein AL and then accumulates in the tissue to form nodules. ACNA seems to be a localized form of AL type amyloidosis, since patients with ACNA have no signs of systemic involvement. |
