| Synonyms:
| Complement C4, serum |
| Specimen: | Blood; (1) SST (serum separator) or Red (no preservative) top vacutainer tube. Patient should be fasting. |
| Volume: | Full primary tube |
| Minimum Volume: | 300 microL serum |
| Collection: | If not tested immediately, transfer serum to a tightly capped plastic aliquot tube.
Refrigerate at 2-8°C for 8 days; freeze at -20°C or lower for up to 3 months. |
| Rejection Criteria: | Incorrect specimen type; improper labeling. |
| Reference Range: | 9 - 40 mg/dL. |
| Methodology: | Nephelometry |
| Test Use: | C4 is a component of the complement system. In general, complement proteins are increased in inflammatory states and decreased in malnutrition, lupus erythematosus, and disseminated intravascular coagulopathus.
Specific indications for quantifying C4 |
| Additional Information: | Repeated freezing and thawing should be avoided. Frozen specimens are stable for up to 3 months. |
| Testing Includes: | Complement C4. |
| Testing Facility: | AnMed Laboratory |