Conjunctival amyloidosis -- clinical and histopathologic features.

Purpose: Conjunctival amyloidosis is a rare disorder. It is often clinically not suspected or diagnosed. This study intended to demonstrate the clinical and histopathologic features of this infrequent disease, including an immunohistochemical search for amyloidotic proteins.
Methods: Retrospective case series of the clinical and histopathologic characteristics of six patients with conjunctival amyloidosis. Immunohistochemical analysis with respect to possible amyloidotic components of the conjunctival deposits was performed.
Results: The diagnosis of amyloidosis was not suspected in all six cases presenting with an amelanotic conjunctival lesion. In three patients a conjunctival tumor of unknown origin, in one case each a papillomatous alteration of the conjunctiva, a conjunctival granulomatous inflammation, and a lymphoma were assumed respectively. The diagnosis of amyloidosis was made by histopathology. Immunohistochemical examination found lambda and kappa light chains as well as prealbumin within the amyloid deposits in one of the six specimens.
Conclusions: The diagnosis of amyloidosis has to be kept in mind in cases with an unclear conjunctival mass or inflammatory process. Only a tissue biopsy is able to prove the diagnosis. A possible underlying systemic disease has to be ruled out.