|Downtime form:||A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery|
|Red top tube 5 mL (Clot Activator)|
Absolute Minimum: 0.5 mL serum from whole blood
Reported as negative or positive
Dense Deposit Disease (DDD, aka Membranoproliferative Glomerulonephritis Type II, MPGNII)
Factor H autoantibodies have been associated with DDD (Meri et al., 1992). In patients with DDD, these autoantibodies bind to and block the N-terminal region of the Factor H protein, which compromises its fluid- phase regulatory function.
Atypical Hemolytic-Uremic Syndrome
Factor H autoantibodies are identified in ~10% patients with aHUS (Dragon-Durey, et al 2005, Moore, et al 2010). Most but not all patients with aHUS who develop Factor H autoantibodies are homozygous for a known polymorphism, del(CFHR3-CFHR1). Homozygosity for this deletion is seen in 15% of patients with aHUS as compared to 5% of controls of northern European ancestry (Zipfel et al 2007, Skerka et al 2009). The Factor H autoantibodies in aHUS patients bind to and block the C-terminal region of the Factor H protein, which interferes with its surface regulatory function (Józsi et al 2007).