Referred Work

Preferred Sample Type


Suitable Specimen Types

  • EDTA Plasma
2 mL

Specimen Transport

1st class post overnight to referral laboratory ( frozen sample) transport on dry ice not required

Sample Processing in Laboratory

Separate within 60 minutes of venepuncture and freeze

Turnaround Time

4 weeks

Sample Stability

Seperate within 60 minutes of venepuncture and freeze prior to overnight transport to referral laboratory


General Information

C3d is a useful marker of complement consumption as it is not affected by the acute phase response, unlike C3 which may remain within the normal range despite significant consumption. This test may be clinical useful to determine whether low complement levels indicate active consumption or deficiency. Determining complement consumption can also be used to monitor disease activity in conditions such as SLE Rhematoid arthritis


Serum samples may give falsely elevated levels of C3d, EDTA plasma must be used.

Reference Range

Normal values <5 mg/L.

Source of Reference Range

Reference range established in referral laboratory


  • EQA Scheme?: No
  • EQA Status: No EQA scheme currently available.

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HTA licence number is 12366

Protection of Personal Information – Laboratory Medicine comply with the Trust Data Protection Policy and have procedures in place to allow the Directorate and it’s employees to comply with the Data Protection Act 1998 and associated best practice and guidance.

The Trust Laboratories at Heartlands Hospital, Good Hope Hospital and Solihull Hospital were awarded UKAS (United Kingdom Accreditation Service) accreditation to the internationally recognised ISO 15189 standard in May 2015. For a list of accredited tests and other information please visit the test database
Tests not appearing on this scope are either under consideration or in the process of accreditation and so currently remain outside of our scope of accreditation. However, these tests have been validated to the same high standard as accredited tests and are performed by the same trained and competent staff.

For further information contact Louise Fallon, Quality Manager, 0121 424 1235