Amyloid light-chain (AL) amyloidosis is a relatively rare disease characterized by abnormal protein deposits. While there are several forms of amyloidosis, AL amyloidosis (also known as primary amyloidosis) is the most common type of this disease.
The number of cases of AL amyloidosis appears to be on the rise in the United States. Understanding this disease is more important now than ever. Awareness of AL amyloidosis is essential to decrease the time to diagnosis and proper treatment. By shortening the time to treatment, the quality of life of people with AL amyloidosis can be improved.
To understand a diagnosis of AL amyloidosis, it is helpful to understand what causes this disease. Antibodies (or immunoglobulins) are proteins produced by the immune system to identify and neutralize infections. Antibodies are manufactured by plasma cells, a specific type of white blood cell. Two kinds of protein make up antibodies: light chains and heavy chains. A light-chain protein is simply the smaller of the two proteins produced by blood plasma cells.
In cases of AL amyloidosis, something goes wrong with the deposition of the light chains. The light-chain proteins become misfolded, and the abnormal proteins begin to accumulate in the organs, causing damage and dysfunction. These accumulations of misfolded proteins are called amyloid fibrils.
Amyloidosis is not technically a form of cancer or leukemia, but it is still a serious disease. Toxic amyloid deposits and their associated fibrils can damage essential organs — including the heart. When amyloid proteins build up in the heart, this is called cardiac amyloidosis.
First, it is helpful to understand the difference between prevalence and incidence. Prevalence refers to the proportion of people who have AL amyloidosis at a given time, whereas incidence refers to the proportion of people who will be newly diagnosed with the condition during that same period. One epidemiological study conducted in France found the yearly incidence of new diagnoses of AL amyloidosis was about 12.5 cases per million inhabitants. The prevalence of AL amyloidosis was 58 cases per million inhabitants.
A similar study in the United States indicated a yearly incidence rate of up to 14 cases of AL amyloidosis per million inhabitants, with a prevalence of 40.5 cases per million inhabitants.
Although the prevalence (as well as incidence) of AL amyloidosis is relatively low compared to some diseases, it is a very serious condition when it does occur.
The risk factors for developing AL amyloidosis include age, gender, family medical history, and the presence of certain health conditions, such as myeloma and diabetes.
The risk of developing AL amyloidosis increases with age. Most of the people diagnosed with AL amyloidosis are over age 40.
AL amyloidosis is more common in men than in women.
Amyloidosis is sometimes linked to other diseases, particularly diseases involving organ failure. Research also shows that people with multiple myeloma, diabetes, and hypothyroidism are more likely to develop AL amyloidosis.
Genes also play a role, and hereditary amyloidosis can be passed along in families. This may be due to changes, or mutations, in DNA. For instance, one DNA change is associated with both AL amyloidosis and myeloma.
What does the diagnosis of AL amyloidosis look like? Diagnosing AL amyloidosis can be a long and complex journey. A diagnosis generally includes blood and urine tests to detect monoclonal proteins.
Other tests performed to assess a potential case of amyloidosis may include:
The symptoms of AL amyloidosis occur as a result of the amyloid protein deposits in the kidneys, heart, digestive system, and nervous system.
Symptoms of AL amyloidosis can include the following:
Read more about symptoms of AL amyloidosis.
Treatment for AL amyloidosis will depend on a person’s age, overall wellness, and any other health conditions they may have. In brief, treatments for AL amyloidosis include:
Read more about treatments for AL amyloidosis.
The disease progression of AL amyloidosis varies depending on the location of symptoms in the body, and it can progress rapidly. In one study of 868 individuals with AL amyloidosis, the median survival period was 3.8 years after diagnosis. Twenty-seven percent of study participants died within one year from diagnosis, often due to symptoms in the heart.
Current treatment options for AL amyloidosis attempt to reduce the production of abnormal plasma cells. Early diagnosis and treatment is key because there are currently no approved therapies to remove existing amyloid deposits that cause organ dysfunction.
MyAmyloidosisTeam is the social network for people with amyloidosis and their loved ones. On MyAmyloidosisTeam, members come together to ask questions, give advice, and share their stories with others who understand life with amyloidosis.
Are you living with AL amyloidosis? Share your experience in the comments below, or start a conversation by posting on your Activities page.