SC5b-9 Level by EIA
Test Code
SC5B9
Description
The complement system is part of our innate immune response. It is vital to our defense against invasive microorganisms. Complement activation can occur through the classical, lectin and alternative pathway, which then converge to a common terminal pathway and assembly of C5b through 9 (C5b-9) on a cell surface or extracellular fluid phase. The fluid phase C5b-9 also known as the soluble C5b-9 (sC5b-9) is a reliable indicator of terminal pathway activation.
The sC5b-9 level can be elevated above normal levels in many conditions associated with inflammation, including infection, renal diseases (IgA nephropathy, C3 glomerulonephritis) as well as thrombotic microangiopathies (TMAs) including shiga toxin-associated hemolytic uremic syndrome, atypical hemolytic uremic syndrome (aHUS). Moreover, elevated concentrations of sC5b-9 are associated with development of transplant-associated TMA after stem cell transplant.
Collect
Plasma from a lavender top (K2- EDTA) tube is the only acceptable sample type. Mix sample thoroughly. Keep tubes cold on wet ice or with a cold pack after collection.
Patient Prep
Within 30 minutes of venipuncture, centrifuge the collection tube at 1600 (± 200) x g (rcf) at 4°C (± 2°C) for 15 (±1) minutes. Transfer the cell-free plasma to a clean tube and immediately store samples at -20°C, or freeze at -60°C or below in an ultra-low freezer.
Preferred volume: 1 mL
Ambient temperature for centrifugation is acceptable provided that the time between collection and storage is minimized (approximately 30 minutes).
Pediatric Collection
Minimum volume: 0.5 ml plasma, frozen
Unacceptable Conditions
Thawed specimen or specimens stored at room temperature prior to shipment.
Storage Transport Temp
Send frozen plasma Priority Overnight via FedEx and in a well-insulated container on dry ice.
Stability
-20°C - up to 4 weeks
-60°C or below in an ultra low freezer - up to 2 years
Notes
Additional testing may be needed for less than perfect samples on confirmatory testing/reflex testing.
Performed
Monday - Friday
Methodology
Enzyme Linked Immunosorbent Assay (ELISA)
Turnaround Time
up to 4 weeks
Department
Complement Lab
Synonyms
C5B9, Soluble C5b-9, soluble membrane attack complex (sMAC), soluble terminal complement complex (sTCC)Study Offerings
CAP/CLIA
Reference Interval
72.0 - 244.0 ng/mL
Interpretation
Elevated SC5b9 levels are indicative of terminal complement pathway activation.CPT Code
86160
New York Approved
No: Run with Waiver
FDA
LDT