Histoplasma and Blastomyces Antigen, Enzyme Immunoassay, Serum
Use
This test is useful for diagnosing Histoplasma capsulatum or Blastomyces dermatitidis infection using serum specimens, without differentiation between the organisms. It is also used to monitor antigen levels following the initiation of antifungal treatment. The test detects Histoplasma and Blastomyces antigens in serum and aids in the diagnosis of histoplasmosis or blastomycosis alongside routine methods such as culture, molecular testing, and serology.
Special Instructions
This test requires serum collected in a serum gel or red top tube. After centrifugation, serum should be aliquoted into a plastic vial for submission. If not ordering electronically, complete a Kidney Transplant Test Request form and send it with the specimen.
Limitations
Due to significant cross-reactivity between galactomannan antigens from Blastomyces and Histoplasma, this assay does not differentiate between the two fungal agents. Positive results should be correlated with clinical and laboratory findings such as culture, serology, and molecular tests. Sensitivity for detecting antigens from species other than Blastomyces dermatitidis or Histoplasma capsulatum is unknown. False-positive results may occur with other dimorphic agents like Coccidioides. Low-level positive antigen levels may persist after infection resolution and treatment completion.
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 101587-4
- 101588-2
- 101589-0
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1.5 mL
Minimum Volume
1.2 mL
Container
Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Causes for Rejection
Gross hemolysis, gross lipemia, gross icterus, heat-inactivated specimen.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 28 days |
| Frozen | 28 days |
