PDF iconKidney Disease Testing Requisition Form (Effective beginning January 3, 2017)

The Clinical Diagnostics Service of the Molecular Otolaryngology and Renal Research Laboratories is a CLIA-approved Joint Commission-accredited diagnostic laboratory.

Plasma Complement C4 Level 
Dense Deposit Disease, C3 Glomerulonephritis and atypical Hemolytic Uremic Syndrome 

Complement C4 (MW: 188 kDa), a central complement component in the classical and lectin pathways, is required to generate C4b2a, the C3 convertase of the classical pathway. C4 is cleaved to C4a (anaphylatoxin; 8 kDa) and C4b (180 kDa). C4b binds C2, and after removal of non-catalytic domain on C2, the C4b2a complex is formed. Unlike plasma C3, plasma C4 levels are typically normal in aHUS and C3G, however this test helps to rule out other complement-mediated renal diseases.

Indications for screening 
Testing is appropriate for patients with aHUS, DDD, and C3GN

MORL screening methodology 
Radial immunodiffusion (RID)

Turnaround time 
Turnaround time is ~ 2 weeks

Sample Required 
1 ml frozen EDTA plasma (see testing requisition for specimen handling).

Cost & CPT Codes
See the MORL testing menu