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C3-Complement (C3)

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EPIC Test Name

C3 COMPLEMENT

EPIC Code

LAB152

Specimen Requirements

plasma
Minimum Volume:0.5 mL
Collection:Collect specimens using standard laboratory procedures.
Transport:Room Temperature ASAP
Stability:Room Temperature: 4 days
Refrigerated: 8 days
Frozen: 8 days
Container:LIT_GRN
Rejection Causes:Hemolysis,
Insufficient Sample Volume

Methods

Immunoturbidimetry

Turnaround Time

SpecimenTurnaround TimeFrequency
plasmaStat: 90 minutes Routine: 4 hours24/7

Reference Ranges

Immunoturbidimetry
All RangeUnit
90-180 mg/dLmg/dL

Clinical Indications

• Complement proteins, the components of the innate immune system, can be activited via 3 pathways: 1) the classic pathway, 2) the alternative pathway, and 3) the lectin activation (mannan-binding protein [MBP]) pathway. Complement factor C3 is a factor common to these pathways, the C3 concentration and its degradation products (including C3c) can be evaluated as a parameter for activation of the complement system. C3 complement factor deficiency may result in infections (e.g., pneumococcal and neisserial infection), as well as autoimmune diseases (glomerulonephritis).
• C3 complement is also an acute phase protein, C3 is increased during inflammatory processes. It is elevated in systemic infections, non-infectious chronic inflammatory conditions (primarily chronic polyarthritis) and physiological states (pregnancy), but its elevation rarely exceeds twice the normal value.

Additional Information

Samples with low or absent of C3 function, while in the presence of normal C3 antigen levels, should be repeated for analysis using a fresh patient sample to verify that C3 inactivation did not take place during shipping process.

Common Synonyms

C3

Performed

Lab
Chemistry - Downtown

Interpretative Information

• Low levels of complement may be caused by deficiency of inherited, acquired or complement consumption origins.
• Commonly, lowered C3 with normal C4 values are indicative of alternative pathway activation.
• Decreased C4 values occur in a number of inflammatory and infectious diseases. Primary causes can be systemic lupus erythematosus (SLE), rheumatoid arthritis, subacute bacterial endocarditis, viremia, parasitic infections or bacterial sepsis.
• A considerable C3 decrease can occur to patients with partial lipodystrophy or membranoproliferative glomerulonephritis when the C3-nephritis factor is present.
• Absent C3 levels in the presence of other normal complement values are consistent with a C3 deficiency.

CPT

86160

LOINC

4485-9

References

1. Davis ML, Austin C, Messmer BL, Nichols WK, Bonin AP, Bennett MJ. IFCC-standardized pediatric reference intervals for 10 serum proteins using the Beckman Array 360 system. Clin Biochem. 1996 Oct;29(5):489-92. doi: 10.1016/0009-9120(96)00046-x. PMID: 8884072.
2. Massey HD, McPherson RA, Huber SA, Jenny NS. Mediators of inflammation: complement, cytokines, and adhesion molecules. In Clinical Diagnosis and Management by Laboratory Methods. 23th edition. Edited by McPherson RA & Pincus MR. WB Saunders Company, 2017, pp 929-43.

Contact Information

Chemistry - Downtown: (315)464-4460
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