Amyloidosis

This is a disease characterized by the accumulation of protein in tissues. Amyloid always accumulates in the extracellular matrix, a condition known as amyloidosis. It can be local or systemic. The latter is divided into membranous and pericollagenous, when it accumulates in the outer or inner layers of blood vessels. Tissues and organs affected by amyloidosis are significantly enlarged, firm, pale, and the cut surface shines like wax. During amyloidosis, due to pressure and impaired nutrition (cells are pushed away from capillaries), tissue cellular structures atrophy, leading to various functional disorders. Most commonly, amyloid accumulates in the kidneys, spleen, liver, brain, gastrointestinal and respiratory tract mucosa, blood vessels, and less frequently in other organs. It mostly accumulates in the cortical layer of the kidneys (glomeruli), leading to death from kidney failure. Amyloid never disappears. In morphological diagnosis, kidney puncture biopsy is usually performed, but less informative yet simpler morphological examinations of the gastrointestinal mucosa (gums, mouth, rectum) are recommended. Patients complain of weakness, fatigue, tingling, bone pain, and digestive disorders. It mostly affects elderly individuals.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė