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Complement C4

General information

Useful in monitoring a wide range of inflammatory and autoimmune disorders. Single point determinations are of limited value and serial measurements are recommended.

Specimen transport: At room temperature

Repeat frequency: At significant change of clinical symptoms, monitoring of treatment

Special precautions: None

Laboratory information

Normal reference range: 0.1-0.4 g/L

Volume and sample type: 7ml clotted blood

Method: Nephelometry

Turnaround time (calendar days from sample receipt to authorised result): Median - 1

Clinical information

Indications for the test: Pre-eclampsia, hereditary angioedema, genetic deficiency, active SLE (associated with low C3) sepsis (associated with low C3).

Factors affecting the test: Traumatic venepuncture and delay in transport can lead to false negative results due to in vitro activation.


ICE reference: C4


(Last updated August 22nd 2018)