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Test Code C-4 Complement, C-4

Useful For

C3 and C4 levels are increased in acute inflammatory states and decreased in malnutrition and hemolytic anemia. Decreased levels of C4 may indicate DIC, acute glomerular nephritis, chronic hepatitis and SLE.

Synonyms/Keywords

C 4 Complement, C4 protein

Specimen Requirements

Fasting Required Specimen Type Preferred Container/Tube Acceptable Container/Tube Specimen Volume Specimen Minimum Volume
(allows for 1 repeat)		 Pediatric Minimum Volume
(no repeat)
No Serum Red Top Tube (RTT) Serum Separator Tube (SST) 0.5 mL serum 0.4 mL serum 0.3 mL serum

Collection/Processing Instructions

Separate serum from cells within 2 hours of collection.

Specimen Stability Information

Specimen Type Temperature Time
Serum
Refrigerated 7 days
Frozen 3 months

 

Rejection Criteria

Plasma samples

Interpretations

Complement levels parallel the activity of circulating immune complex disease.  Decreased levels can indicate increased disease activity and normalized levels may indicate remission.  Falling levels may precede relapse.  Persistent low C-3 and C-4 levels may indicate complement deficiency, either congenital or acquired.

Reference Range Information

Performing Location Reference Range
Marshfield

14.0-40.0 mg/dL

Marshfield Labs Performing Department

Marshfield Labs Immunodiagnostics

Performing Information

Performing Location Day(s) Test Performed Analytical Time Methodology/Instrumentation
Marshfield Monday through Friday

6-8 hours

Analytic time may be extended if single frozen specimen is sent for multiple tests

 Turbidimetric method/The Binding Site Optilite analyzer

CPT Codes

CPT Modifier
(if needed)		 Quantity Description Comments
86160        

Outreach CPT Codes

CPT Modifier
(if needed)		 Quantity Description Comments
86160        

Ordering Applications

Ordering Application Description
Cerner Complement C4 (C4)
COM Complement, C-4