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0203 313 5353

Complement, total alternative pathway

Category Immunology
Test background

The AP50 assay measures the ability of serum complement components to form membrane attack complex, which can be detected by ELISA. C3 and C4 levels must also be requested. The assay is used as a screening test for defects of individual components of the alternative and terminal pathways. It should not be used for monitoring complement consumption, instead request C3 and C4 levels.

Clinical Indications

Suspected complement deficiency
Recurrent infections
Recurrent Neisseria infections

Reference range

50-125 % of normal

Sample & container required RST (rust top) Separate and freeze immediately Transport frozen
Sample volume 5-10 mL (1 mL serum)
Turnaround time 21 days