What does light chain MGUS mean?
Pelzer et al concluded that light-chain MGUS—defined as an abnormal FLC ratio, increase of involved FLC with complete loss of immunoglobulin heavy chain, and absence of a history of lymphoproliferative disease—is a relatively benign condition, and that the monoclonal protein often diisappears over time.
How common is light chain MGUS?
LC-MGUS is prevalent in approximately 1% of a predominantly Caucasian, general population and poses a risk of progression to light-chain MM and related conditions comparable to that of low-risk MGUS. LC-MGUS was also associated with a risk for renal disease.
What is abnormal light chain ratio?
An abnormal kappa-lambda FLC ratio indicates an excess of one light chain type versus the other, and is interpreted as a surrogate for clonal expansion based on extensive testing in healthy volunteers, and patients with myeloma, amyloidosis, and renal dysfunction.
What is Kappa-Lambda ratio in MGUS?
In general, a low kappa-lambda ratio (< 0.26) indicates the overproduction of lambda light chains, and a high ratio (> 1.65) indicates the overproduction of kappa light chains. A kappa-lambda ratio below 0.37 or above 3 is rarely seen in chronic kidney disease and should prompt workup for MGUS. Tests in combination.
How do you know MGUS is progressing?
People with MGUS need to be monitored with blood and urine testing every 6 to 12 months to determine if MGUS is progressing. For a small percentage of individuals, the condition develops into cancerous conditions, such as multiple myeloma or lymphoma.
What is considered low risk MGUS?
People who have low-risk MGUS have the following features: The M-protein level is less than 15 g/L. The type of M-protein is IgG. The free light chain ratio is normal.
What is considered high risk MGUS?
People who have high-risk MGUS have any of the following features: The M-protein level is more than 15 g/L. The type of M-protein is IgA or IgM. The free light chain ratio is abnormal.
What does abnormal free light chains mean?
amyloidosis
If the amount of free light chains is higher or lower than normal, it can mean you have a disorder of the plasma cells. These include multiple myeloma, a cancer of plasma cells, and amyloidosis, a condition that causes a dangerous buildup of proteins in different organs and tissues.
What is a normal free light chain ratio?
0.26 to 1.65
Normal test results for free light chains are: 3.3 to 19.4 mg/L kappa free light chains. 5.71 to 26.3 mg/L lambda free light chains. 0.26 to 1.65 ratio of kappa/lambda.
What does high free kappa and lambda light chains mean?
A free light chains test measures the amount of lambda and kappa free light chains in the blood. If the amount of free light chains is higher or lower than normal, it can mean you have a disorder of the plasma cells.
What are the criteria for light chain MGUS?
I’ve checked several articles on this subject, and the criteria for a diagnosis of light-chain MGUS are usually described this way: Abnormal FLC ratio (<0.26 or >1.65) Increased level of the appropriate involved light chain (increased kappa FLC in patients with ratio >1.65 and increased lambda FLC in patients with ratio <0.26)
How to tell if you have monoclonal gammopathy ( MGUS )?
MGUS is characterized by a monoclonal protein (M protein) < 3 g/dL (30 g/L) in the serum and < 10% monoclonal plasma cells in the bone marrow and no evidence of end-organ damage (“CRAB”: hypercalcemia, renal insufficiency, anemia or bone lesions), lymphoma, Waldenström macroglobulinemia, or light chain amyloidosis (AL).
Is there a serum light chain for gammopathy?
Blood 2005; 106 (3): 812–817. doi: https://doi.org/10.1182/blood-2005-03-1038 We hypothesized that the presence of monoclonal free kappa or lambda immunoglobulin light chains in monoclonal gammopathy of undetermined significance (MGUS), as detected by the serum free light chain (FLC) assay increases the risk of progression to malignancy.
How many people have an abnormal light chain?
Findings: 610 (3.3%) of 18,357 people tested had an abnormal free light-chain ratio, of whom 213 had IgH expression that was diagnostic of conventional MGUS. 146 of the remaining 397 individuals had an increase of at least one free light chain and met criteria for light-chain MGUS.