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:
Factor I is a protein which regulates the complement cascade. Deficiencies of Factor I are rare, but are associated with immune mediated kidney diseases such as atypical haemolytic uraemic syndrome (aHUS) and C3 Glomerulopathy (C3G), and in extremely rare cases neurological inflammation.
Specimen container paediatric:
Serum-Plain tube
Specimen container adult:
Serum-SST
Minimum volume paediatric:
0.5 ml
Minimum volume adult:
1 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:
Serum may be stored at 4 degrees for a maximum of 48 hours then stored for 1 year at -80 degrees. Samples should not be freeze thawed prior to testing.
Freq analysis:
Weekly
Add on test:
All urgent add ons via telephone on 0191 282 4766, and must be confirmed via email to the appropriate email address [email protected]
Interpretation:
Low Factor I levels may be caused by complement consumption, for example during ongoing infection or inflammation or by genetic deficiencies.
Genetic deficiencies of Factor I are associated with aHUS and C3G.
Reference ranges:
>18mg/L
Other info:
Factor I levels are usually measured alongside Factor H levels. Both are measured via ELISA.