Amyloidosis is a term that refers to a variety of disorders, characterized by the deposition of amyloid proteins in several organs and tissues.
Amyloids are fibrillar insoluble protein condensates that acquire a terciary conformation, known as beta-pleated sheat.
Patients with amyloidosis can be divided into three groups: primary familial amyloidosis (PFA), familial amyloidotic polyneuropathy (FAP) and secondary amyloidosis. Only PFA and FAP are associated with vitreous deposits.
In PFA, portions of immunoglobulin light chains form tissue deposits (AL amyloid). FAP is related to mutations in the protein transthyretin (most commonly at locus 18q11.2-q12.1), inherited in an autosomal dominant fashion.
Systemic clinical features include renal dysfunction, cardiomyopathy and peripheral neuropathy.
