Pemphigoid Gestationis, Complement-Fixing Basement Membrane Antibodies (Herpes Gestationis Factor)
Also known as: HG FACTOR
Use
This test is primarily used as the preferred panel to assess and monitor pemphigoid gestationis (also known as herpes gestationis) and other immunobullous diseases characterized by complement-fixing basement membrane zone antibodies. This specific immunodermatology serum test is performed to detect complement-fixing (herpes gestationis factor) and noncomplement-fixing IgG basement membrane zone antibodies. The presence of these antibodies supports the diagnosis of pemphigoid gestationis, a rare autoimmune blistering disorder occurring in pregnancy. The test leverages a combination of Semi-Quantitative Complement Fixation, Indirect Immunofluorescence, and Semi-Quantitative Enzyme-Linked Immunosorbent Assay (ELISA) methodologies for thorough identification and quantification.
Special Instructions
Testing should be correlated with concurrent direct immunofluorescence, tissue biopsy, and possibly other complementary serum tests for comprehensive disease understanding. For specimens less than 0.5 mL, consultation with the Immunodermatology Laboratory (801-581-7139) is advised.
Limitations
The test is performed by a non-ARUP laboratory and its methodologies, although developed and performance characteristics determined by the Immunodermatology Laboratory at the University of Utah, have not been cleared or approved by the FDA, as FDA approval is not required for tests conducted in a CLIA-certified laboratory. Despite thorough testing procedures, results do not rule out other immunobullous diseases and should be considered alongside clinical findings and additional diagnostic insights. Results may vary with disease activity and specimen characteristics, such as severe hemolysis or lipemia.
New York Approved
Methodology
Immunoassay (IIF)
Biomarkers
LOINC Codes
- 45179-9
Result Turnaround Time
7-14 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
2 mL
Minimum Volume
1 mL
Container
ARUP standard transport tube
Collection Instructions
Collect in a plain red or serum separator tube (SST).
Storage Instructions
Store refrigerated unless shipping promptly (within 2 hours). Transport at ambient temperature to arrive within 7 days. If 7-14 days until received in laboratory, store and ship refrigerated. If greater than 14 days, serum specimens must be stored and shipped frozen.
Causes for Rejection
Hemolyzed or lipemic specimens. Plasma.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 2 weeks |
| Frozen | Indefinitely |