Specimen: 2 mL (0.5 mL min.) serum from 1 SST. Ship refrigerated or frozen. Overnight fasting is preferred.
Stability (Room): 8 hrs
Stability (Refrigerated): 1 week
Stability (Frozen): 2 weeks
Comment: Also see HISTOPATHOLOGY, DIRECT IMMUNOFLUORESCENCE TESTS.
Price: Contact Medilab
Turnaround time (TAT): 5 – 15 days
Usage: C4 is critical to activation of classical pathway. Decreased levels are seen in patients with SLE, Immune Complex disease and Hereditary angioedema. Congenital deficiency of C4 increases the risk of recurrent bacteremia especially S.pneumoniae. This assay is useful in the diagnosis of C4 deficiency and for investigation of a patient with an undetectable Total complement (CH50) level.
Specialty: Nephrologist, Physician
Disease: Disorders of Complement system
Home Collection: Available
Pre-test Information: Overnight fasting is preferred.