[Localized primary cutaneous nodular amyloidosis]. / Amiloidosi nodulare cutanea primaria localizzata.

A case of cutaneous nodular amyloidosis in a 60-year-old man is described with reference to histological, immunohistochemical and ultrastructural features. Clinically, the patient presented two brownish nodules on his face. Histologically, a massive dermal collection of eosinophilic, homogeneous material showing positivity for Congo red stain was revealed. Immunoreactivity for both Ig-light chains was detected in dermal plasma cells as well as in amyloid material. Ultramicroscopically, the typical fibrillary pattern of amyloid was found. Clinical and instrumental examinations failed to demonstrate amyloid depositions elsewhere in the body.