BLASTOMYCES IgG ANTIBODY EIA

Test Code

331
CPT Code

86612
Clinical Significance

This assay indirectly detects anti-Blastomyces IgG by recognizing the BAD-1 repeat surface protein. This test offers an improvement in sensitivity over the current methods of detecting antibodies by immuno diffusion and complement fixation. The Blastomyces Antibody IgG EIA is useful for diagnosing blastomycosis in patients with negative antigen results. Secondly, when both Histoplasma and Blastomyces antigen assays are positive, comparing Histoplasma and Blastomyces antibody concentrations may assist in establishing the correct diagnosis. Additionally, following changes in antibody concentration via repeat testing may determine whether the infection has resolved or if relapse has occurred.
Methodology

Semi-Quantitative Indirect Enzyme Immunoassay (EIA)
Limitations

Cross-reactions occur with Histoplasma capsulatum.
Specimen Collection
- Serum: Serum separated from the clot in a leak-proof container.
- Plasma: Sterile leak-proof container.
- New York approved for Serum samples.
Minimum Specimen Requirements

Serum/Plasma*: 0.25 mL

* Plasma reported with rare specimen comment applied.
Specimen Stability
- Room Temperature: 30 days
- Refrigerated: 30 days
- Frozen: 30 days
Specimen Rejection

Any specimen type other than serum or plasma
Transport Temperature

Ambient/Refrigerated/Frozen
Shipping

Ship to arrive Monday‐Friday using a next day delivery service. Samples may be shipped on dry ice, frozen ice packs, or ambient.
Turnaround Time

Same day**

**Test Set up: Samples for Antigen testing received by 10:30AM will have same day test set up. Positive samples may require confirmation, which could extend turnaround time. Serum & CSF specimens are pre-treated to improve sensitivity, which can add one day to turnaround time.
Reference Range

Negative
Interpretative Information
- Negative: < 10.0 EU
- Intermediate: 10.0 EU – 13.9 EU
- Positive: 14.0 EU to ≥ 80.0 EU
Results should be correlated with clinical presentation and history.

* New positives may require confirmation.

** Turnaround times are provided as ranges, and may vary depending on daily testing volumes and specimen type.

*** Test set-up: Samples received by 10:30 AM are eligible for same-day testing. Same-day testing is not guaranteed and may vary based on daily test volume, sample receipt time, testing schedules, and sample type. Some samples may require pretreatment and/or confirmatory testing, which can extend turnaround time (TAT).

**** Two unique patient identifiers are required on specimen containers.

***** Specimens with particulate matter or viscosity that would not allow the specimen to be pipetted will be rejected.