Difficulties in the diagnosis of primary amyloidosis: case report

Abstract

Amyloidosis consists of a group of diseases that have in common the extracellular deposition of a substance composed primarily of amyloid type proteins. Amyloid proteins have ultrastructural and biochemical specific properties that, through specific staining methods, demonstrate their fibrillar character and structure and distribution in the tissue in which they are deposited. The physical presence of deposits of an amyloid substance can cause dysfunction in tissues and organs by the interaction of fibrils with local receptors and deposit cytotoxicity. The clinical presentation varies according to the affected tissue and organ; it can be subtle and nonspecific, such as fatigue and weight loss, and serious with renal, cardiac, and gastrointestinal insufficiency and peripheral autonomic and/or sensitive-motor neuropathy. In general, though several organs may be affected, one form might dominate. Amyloidosis can be primary, hereditary, or associated with various clinical situations; being primary if it is not associated with any other disease. The secondary form of the disease occurs primarily associated with neoplasms and inflammatory or chronic infectious diseases.