Medicines for Amyloidosis

What it is

Amyloidosis is the name for a group of rare, serious conditions in which an abnormal protein called amyloid builds up in organs and tissues throughout the body. Amyloid is formed when proteins that are normally soluble fold abnormally and clump together, forming deposits that accumulate in tissues and can interfere with how the affected organs work. There are several different types of amyloidosis, which differ in the type of protein involved, which organs they affect, and their causes — for example, some types are related to an abnormality in the bone marrow producing an abnormal protein (such as AL amyloidosis, related to plasma cells); some are related to long-term inflammation from another chronic condition (AA amyloidosis); some are inherited (hereditary amyloidosis); and some are related to ageing or other factors. Because amyloid can build up in different organs, amyloidosis can affect many parts of the body, and the symptoms depend on which organs are affected — commonly, it can affect the heart (causing heart problems and symptoms such as breathlessness, swelling, and tiredness), the kidneys (affecting kidney function, sometimes with fluid retention and other effects), the nerves (causing numbness, tingling, weakness, or effects on the automatic nervous system), the digestive system, and other organs; general symptoms such as tiredness and weight loss can also occur. Because the symptoms are varied and can overlap with many other conditions, and because amyloidosis is rare, it can be difficult to diagnose, and diagnosis (which involves identifying the amyloid, for example in a tissue sample, and determining the type) is important, as it guides treatment. Amyloidosis is a serious condition, but treatments are available, and the outlook and treatment depend heavily on the type and which organs are affected. Treatment generally aims to reduce the production of the abnormal protein (to slow or stop further amyloid building up) — for example, treating the underlying cause (such as the bone marrow abnormality in AL amyloidosis, often with treatments similar to those used for related blood conditions, or the chronic inflammation in AA amyloidosis) — and to support the affected organs and manage symptoms; specific treatments exist for some types, and this is a developing area. Care is provided by specialists, often at specialist amyloidosis centres. The key messages are that amyloidosis is a group of rare conditions where an abnormal protein builds up in organs and tissues, that the symptoms and treatment depend on the type and organs affected, and that specialist care is important.

How it is treated

Amyloidosis is managed by specialists (often at specialist amyloidosis centres), with treatment aimed at reducing the production of the abnormal protein and supporting the affected organs, tailored to the type; diagnosis and determining the type are crucial, as they guide treatment. Because amyloidosis is rare and its symptoms are varied and overlap with many conditions, reaching a diagnosis can be challenging and involves specialist assessment and tests — including identifying the amyloid deposits (for example through a tissue sample/biopsy), determining the type of amyloidosis (which is very important, as the types differ greatly in cause, organ involvement, treatment, and outlook), and assessing which organs are affected and how (with tests such as heart, kidney, and other assessments and specialised scans); specialist amyloidosis centres have the expertise for this. Treatment then depends heavily on the type and the organs involved. A general principle is to reduce the production of the abnormal protein, so that less amyloid is formed and further build-up is slowed or stopped, allowing the body to gradually clear existing deposits over time in some cases — how this is achieved depends on the type: for AL amyloidosis (related to an abnormality in plasma cells in the bone marrow), treatment targets the abnormal cells producing the protein, often using treatments similar to those for related blood conditions (such as chemotherapy-based or other targeted treatments), which has improved outcomes; for AA amyloidosis (related to long-term inflammation), treating the underlying inflammatory condition to control the inflammation reduces the protein driving the amyloid; for hereditary amyloidosis, specific treatments (including newer treatments that target the abnormal protein) may be available; and other types are treated according to their cause. Alongside treating the cause, supporting the affected organs and managing symptoms are important — for example, managing heart or kidney involvement and their effects, managing nerve or other symptoms, and general supportive care; in some situations, treatments such as organ support or, in selected cases, transplantation may be relevant. This is a developing field, with newer treatments improving the outlook for some types. Care is coordinated by specialists, with monitoring over time, and support for the person and family is important given the seriousness and complexity. The reassuring messages are that, although amyloidosis is a group of rare and serious conditions, treatments are available and have improved, that treatment is tailored to the type (aiming to reduce the abnormal protein and support the organs), and that specialist care (often at specialist centres) is important for accurate diagnosis and the best treatment; so specialist assessment, determining the type, and appropriate, type-specific treatment are the keys to managing amyloidosis.