Amyloidosis is the name given to a group of rare disorders in which amyloid deposits, consisting of misfolded proteins deposit and accumulate in tissues and organs of the body. As these deposits progressively build up they interfere with the working of the organs. Without treatment this will eventually leads to organ failure.
There are several types that are seen in clinical practice:
- Wild-type transthyretin (ATTR)
- Common type that predominantly affects the older population (age >60) with a strong male predominance
- Heart involvement is by far the predominant organ involvement
- Often preceded by carpal tunnel syndrome in a large number of patients (~3-5 years prior to the diagnosis)
- Hereditary transthyretin (variant ATTR)
- Much less common than wild-type
- Occurs when a gene mutation is inherited, leading to a life-long production of an abnormal transthyretin protein
- Symptoms are dependent on the type of mutation but can vary between predominantly neurological, predominantly cardiac, or a mix of both
- Light chain (AL)
- Occurs due to misfolded immunoglobulin light chains that are produced by plasma cells in the bone marrow
- Usually these plasma cells are benign, but occasionally the amyloid forming light chain protein can be produced by a cancer of plasma cells called Multiple Myeloma
- About 15% of patients with Multiple Myeloma will also develop AL amyloidosis
- AA amyloid
- Clinically significant heart involvement is rare
- Occurs with a prolonged and substantial increase the Serum Amyloid A (SAA) protein (released by the body during states of inflammation
- Seen in the context of a long-term inflammatory disorder such as rheumatoid arthritis
Treatment is very different for each type of amyloidosis and is always geared to the needs and health of the individual patient.
Treatment should ideally be recommended after careful review by experienced amyloidosis treatment teams.