Cutaneous Immunofluorescence Antibodies, IgG and IgG4, Serum
Use
This test is useful for confirming the presence of IgG and/or IgG4 antibodies to diagnose pemphigoid, pemphigus, epidermolysis bullosa acquisita, or bullous lupus erythematosus. These conditions are associated with autoimmune blistering disorders where patients produce IgG and/or IgG4 anti-basement membrane zone (BMZ) antibodies. The detection of these antibodies aids in the diagnosis of such disorders. The sensitivity of detection is increased by testing serum using sodium chloride-split primate skin and primate esophagus as substrates with both IgG and IgG4 reactants.
Special Instructions
The testing algorithm includes reflex titer measurement of IgG when anti-cell surface or anti-basement membrane zone antibodies are present. This additional test is performed at an extra charge. The report includes the presence and titer of circulating antibodies and patterns such as epidermal, dermal, or mixed patterns are reported to aid in differential diagnosis.
Limitations
Results should be interpreted alongside clinical information, histopathologic, direct immunofluorescence studies, and histopathologic patterns. Low titer antibodies should not be used alone for diagnosis without such support. The test is performed using indirect immunofluorescence assays.
New York Approved
Methodology
Immunoassay (Indirect Immunofluorescence Assay (IFA))
Biomarkers
LOINC Codes
- 93233-5
- 29994-1
- 104832-1
- 48767-8
Result Turnaround Time
2-7 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
2 mL
Minimum Volume
0.5 mL
Container
Serum gel (preferred), Red top (acceptable), Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 30 days |