Classical Complement Pathway Activity (CH50)
Test Code
CM50
Description
Collect
Serum from a plain red top is the only acceptable sample type.
Gel barrier tubes are not acceptable.
Specimen Preparation
Allow blood to clot at room temp or 37°C for 20 to 60 minutes. Centrifuge to thoroughly remove cells and immediately transfer cell-free serum to a fresh tube and freeze the cell-free serum on dry ice or at -70°C.
Preferred volume: 1 mL
Pediatric Collection
Minimum volume: 250 µL serum, frozen
Unacceptable Conditions
Thawed specimen.
Storage Transport Temp
Send frozen serum Priority Overnight via FedEx and in a well insulated container on dry ice.
Stability
Frozen at -70°C: 1 year
Methodology
Hemolytic Assay
Reported
up to 4 weeks
Department
Complement LabSynonyms
Hemolytic Assay (Classical Complement Pathway Activity);Classical Complement Pathway Activity;Complement (Classical Complement Pathway Activity), & CM50
Related Tests
Primary Immunodeficiency Screen: Pneumococcal polysaccharide IgG antibody [12 serotypes] (PNU12), Diphtheria IgG antibody titer (DIPHT), Tetanus IgG antibody titer (TET), Lymphocyte enumeration, CDC panel [CD3/CD4, CD3/CD8, CD19, CD16/56] (TBCDC), CBC with automated diff (HCBC), Immunoglobulin A level (IGA), Immunoglobulin G level (IGG), Immunoglobulin M level (IGM), Alternative complement pathway activity (AH50)
Complement Assessment: Alternative complement pathway activity (AH50), Mannose binding lectin [MBL] level (MLEC)
Reference Interval
Human Male: 176-382
Human Female: 176-382
CPT Code
86162