Verifying the analysis of complement component C3 and C4 on Siemens Atellica NEPH 630

The complement components C3 and C4 are part of the complement system. The complement system has many tasks to perform in the body and consists of several proteins that all have unique tasks. C3 and C4 are examined, for example, if a deficiency is suspected, in the presence of autoimmune diseases or in the case of recurring bacterial infections. When verifying the analysis and after analyzing of external controls, it has been shown that the reference range is falsely high, especially for C3. The study therefore aimed to verify the analysis of C3 and C4 on Atellica NEPH 630 and establish a correct reference range for respective analysis. The method was verified by evaluating the precision of the method and by comparing the concentration of C3 and C4 measured on Cobas 6000 module C500 with the concentration measured on Atellica NEP 630. In addition, the reference intervals provided by Siemens were evaluated using samples from blood donors and from other healthy individuals. The verification began by performing quality controls on three different levels before analysis of samples. The coefficient of variation was less than 5 % for all control levels for both complement analysis. Reference values ​​for C3 were not in alliance with the reference values ​​provided by Siemens. A new proposed range for C3 is 0.48- 1.37 g/L, while the recommended range can be used for C4