Beta-2-Microglobulin

For Specimen Integrity during Extreme Weather see the “Lockbox Usage in Extreme Weather” document at the top of this page.

B2MC

852;
B2-MIC;
Microglobulin;
Beta2

serum

0.5 mL

plasma from Lithium Heparin (Light Green Top) tube

Barrier tubes (serum separator tubes or plasma separator tubes) are preferred. If non-barrier tubes are utilized, the serum/plasma must be removed immediately after centrifuging and placed in a screw-cap transfer tube.

Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.

Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.

Original tube preferred, may be sent in a screw-top transfer tube.

Refrigerated

Room Temperature = n/a
Refrigerated = 3 days
Frozen = 6 months

Hemolysis, Lipemia, incorrect specimen type, insufficient sample volume, improper storage conditions, exceeds specimen stability guidelines, contaminated sample.

Daily
AU

daily

Beta-2-microglobulin normally passes through the glomerulus into the proximal tubule where much of it is reabsorbed. Serum levels are therefore an index of glomerular function. When impaired, serum levels rise in inverse ratio to glomerular filtration rate. Increased amounts of beta-2-microglobulin are excreted in several renal disorders, e.g., Balkan nephropathy, heavy metal poisoning and renal tubular disease due to therapeutic agents. Serial levels of beta-2-microglobulin in serum and urine are used to evaluate transplant viability and anticipate rejection. Following a successful graft, serum levels decline toward normal. Increasing serum levels provide an early sign of rejection. Elevated levels are also noted in lymphproliferative disorders, neoplasms (malignant and benign), inflammatory disease, and autoimmune diseases such as systemic lupus erythematosus (SLE) and Sjögren's disease.