C3 (Complement C3)

Alternate Name: C3

SAL Code:

1967

CPT:

86160

Loinc:

4485-9

Turn Around Time:

1 Day

Setup:

Daily

Units:

mg/dL

Department:

Diagnostic Immunology

Specimen Requirements:

Primary Tube:

SST

Primary Substance:

Serum

Temperature

Period

Stable Ambient:

7 Days

Stable Fridge:

7 Days

Stable Frozen:

28 Days

Rejection Criteria:

Gross hemolysis; lipemia; improper labeling

Clinical Info:

Quantitation of C3 is used to detect individuals with inborn deficiency of this factor or those with immunologic disease in whom complement is consumed at an increased rate. These include lupus erythematosus, chronic active hepatitis, certain chronic infections, poststreptococcal and membranoproliferative glomerulonephritis, and others.

Additional Information:

C3 comprises about 70% of the total protein in the complement system and is central to activation of both the classical and alternate pathways. Increased levels are found in numerous inflammatory states as an acute phase response. CH50 (total complement hemolytic activity), C3 and/or C4 may be decreased in cases of systemic lupus erythematosus, especially in cases with lupus nephritis, acute and chronic hypocomplementemic nephritis, subacute bacterial endocarditis, DIC, and partial lipodystrophy (with associated nephritis-like activity in serum.) In cases of disseminated intravascular coagulation, plasmin attacks C3 directly, and C3 levels have been found low in the hemolytic uremic syndrome form of disseminated intravascular coagulation (DIC). Cases of hereditary C3 deficiency, while rare, have been reported and are characterized clinically by recurrent infections (eg, pneumonia, meningitis, paronychia, impetigo). Pathogenic bacteria causing infections in these cases have included both gram-positive and gram-negative organisms. C3 levels have also been found deficient in cases of uremia, chronic liver diseases, anorexia nervosa, and celiac disease.

Sample Collection:

Collect patient samples using standard phlebotomy techniques. Click here for additional collection instructions.

Test Information:

Components: