Amyloidoses are a group of very rare diseases that commonly accumulate an abnormal substance called amyloid in the organs. More than 40 different types of amyloidoses are currently known. Amyloid looks similar under the microscope in all of these diseases, but the protein that is its main building block differs in each. Genetic, neoplastic or inflammatory disorders contribute to the formation of amyloid-building proteins in different types of amyloidosis.

Amyloid is deposited between the cells of various organs, which after some time (sometimes many years), leads to deterioration of the function of these organs and eventually to their failure. This progressive process is the source of various clinical symptoms and general deterioration of health, and if left untreated, often leads to the death of the patient. Among the most commonly affected organs by amyloid are the heart and kidneys. For this reason, amyloidosis patients often suffer from kidney failure, heart failure or both organs simultaneously. However, amyloid can be deposited in almost all other organs, such as the liver, nerves, skin or intestines. The most common amyloidoses include:

• AL amyloidosis (or light chain amyloidosis) – accounts for more than 70-80% of all amyloidoses. It is a bone marrow malignancy related to plasmocytic myeloma (multiple myeloma), in which amyloid comprises immunoglobulin fragments secreted by neoplastic plasma cells in the bone marrow. The heart or kidneys are often involved, but the disease usually affects multiple organs.
• Transthyretin amyloidosis (ATTR amyloidosis), is further divided into an acquired form and an inherited form. In acquired ATTR amyloidosis, there is deposition of amyloid made up of transthyretin protein. The acquired form affects almost exclusively the heart and occurs primarily in older men, while hereditary ATTR amyloidosis occurs at any age and can affect the nerves, heart or, less commonly, other organs
• secondary amyloidosis (AA amyloidosis). This disease can be a complication of chronic inflammation, e.g., in rheumatologic diseases, certain infections or cancer, and primarily occupies the kidneys. However, one should not forget the need to recognize the other, much rarer types of amyloidosis.

Despite the fact that amyloidoses are rare diseases, collectively, they can affect a relatively large group of patients, many of whom have the disease undiagnosed. The incidence of amyloidoses in Poland is unknown, but based on data from other countries, it can be thought that the diseases may affect up to several thousand people. The number of new cases is probably a few hundred per year. Since the number and type of organs involved vary from patient to patient, the clinical picture can be very different even in patients with the same type of amyloidosis, making it difficult to make a correct diagnosis. This is all the more difficult because these diseases are very rare and often little known even to specialists in their respective fields of medicine. In addition, the diagnosis of amyloidoses, and especially the determination of the type of amyloidosis, is complicated in many situations.

The low diagnosis of amyloidoses in Poland is particularly unfavorable now that there are effective treatment options for the most common types of amyloidosis, i.e. targeted therapies for AL amyloidosis and ATTR amyloidosis. These therapies can inhibit the progression of the disease, reduce organ symptoms, and prolong the life of patients. The treatment of amyloidosis is difficult and requires the coordinated cooperation of many specialists, including hematologists, cardiologists, nephrologists and neurologists.

More detailed information about amyloidosis in Polish can be obtained from the website of the Polish Amyloidosis Network (www.amyloidoza.edu.pl). This website is intended for physicians in various fields related to the diagnosis or treatment of amyloidosis and for patients with the disease and their family members. It contains accessible information about the disease, diagnostic methods and treatment of amyloidosis, and a selection of updated, recent scientific reports on clinical and scientific advances in the field.