Complement C4

Low C4 levels can occur in hereditary and acquired angioneurotic oedema.

Reference Ranges

Adults10 – 40 mg/dL0.1 – 0.4 g/L
Each laboratory should check if the reference ranges are transferable to its own patient population and determine own reference ranges if necessary. For diagnostic purposes, the results should always be assessed with the patient’s medical history, clinical examinations and other findings.

Increased in

  1. Acute phase reaction

Decreased in

  1. Complement comsumption due to infection or auto immune reaction


< All Reference Ranges