Davis's Lab & Diagnostic Tests

Complement C3 and Complement C4

Complement C3 and Complement C4 is a topic covered in the Davis's Lab & Diagnostic Tests.

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C3 and C4.

Common Use:
To assist in the diagnosis of immunological diseases, such as rheumatoid arthritis, and systemic lupus erythematosus (SLE), in which complement is consumed at an increased rate, or to detect inborn deficiency.

Serum collected in a red- or red/gray-top tube. Place separated serum into a standard transport tube within 2 hr of collection.

Normal Findings:
(Method: Immunoturbidimetric)

AgeConventional UnitsSI Units (Conventional Units × 0.01)
Newborn57–116 mg/dL0.57–1.16 g/L
6 mo–adult74–166 mg/dL0.74–1.66 g/L
Adult83–177 mg/dL0.83–1.77 g/L

AgeConventional UnitsSI Units (Conventional Units × 0.01)
Newborn10–31 mg/dL0.1–0.31 g/L
6 mo–6 yr15–52 mg/dL0.15–0.52 g/L
7–12 yr19–40 mg/dL0.19–0.4 g/L
13–15 yr19–57 mg/dL0.19–0.57 g/L
16–18 yr19–42 mg/dL0.19–0.42 g/L
Adult12–36 mg/dL0.12–0.36 g/L

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