Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
This should be measured in cases of angioedema with low C4, when the total immunochemical C1-esterase inhibitor level is normal or high.
Specimen container paediatric:
Serum-Plain tube
Specimen container adult:
Serum-SST
Minimum volume paediatric:
2 ml
Minimum volume adult:
2 ml
Special requirements:
Samples MUST be separated within 4 hours of venesection. Please ensure that the sample arrives in the laboratory as soon as possible after being taken.
Sample stability:
Stored for 1 year at -80 degrees. Samples should not be freeze thawed prior to testing.
Freq analysis:
Fortnightly
Add on test:
Cannot be added on due to stability issues. Please discuss with the Protein Laboratory.
Quality assurance:
UK NEQAS for C1 Inhibitor and Functional ComplementINSTAND Complement EQA scheme
Interpretation:
Low levels are associated with HAE. However due to stability of C1 esterase inhibitor low levels should be discussed with Immunology.
Reference ranges:
Normal Adult Range: 70 -130% [expressed as % activity when compared to the control serum]
Other info:
Reported as a % of the activity of the control serum used in the assay.