Complement C1 esterase inhibitor
Immunology
Sample and container requirements
Serum
Minimum volume required
4 ml Blood
Special requirements
none
Patient preparation
None
Sample viability
Stable at 4 C for 8 days, If longer storage is anticipated then samples may be frozen prior to analysis
Turnaround time
7 days
Reference range
0.15-0.35g/L
Clinical guidance
Low levels of C1 inhibitor may indicate Hereditary Angioedma. These cases should be discussed with an immunologist for possible referral and further investigation. Normal levels of C1 inhibitor but having a clinical picture of C1 inhibitor deficiency should be investigated for functional C1 inhibitor defects. To allow correct interpretation of results concurrent complement C3 and C4 levels should be requested. https://labtestsonline.org.uk/tests/complement
Notes
Images to go here
This information was last updated on 19 August 2026