Laboratory Test Guide

Histoplasma Antigen, Urine (Sendout)

General Information

Lab Name

Histoplasma Antigen, URN

Lab Code

RHSTOU

Epic Name

Histoplasma antigen, Urine (Sendout)

External Test Id

HSTQU

Description

Useful For:

Aiding in the diagnosis of Histoplasma capsulatum infection
Monitoring Histoplasma antigen levels in urine

References

Mayo Clinic Laboratories Histoplasma Antigen, Urine Clinical & Interpretive Information

Synonyms

Histoplasma capsulatum, Histoplasma galactomannan antigen, Histoplasma Polysaccharides, HSTQU

Components

Code	Name
RUHSTR	Histoplasma Ag Result, URN
RUHSTV	Histoplasma Ag Value, URN

Interpretation

Method

Enzyme Immunoassay (EIA)

Reference Range

See individual components

Ref. Range Notes

Reference Values:

Histoplasma Antigen Result:	Not Detected
Histoplasma Antigen Value:	Not Detected

Histoplasma Antigen Value Interpretation:

Not Detected: No Histoplasma antigen detected. False-negative results may occur. Repeat testing on a new specimen should be considered if clinically indicated.
Detected, <0.2 ng/mL: Histoplasma antigen detected below the limit of quantification (<0.2 ng/mL). Results should be correlated with clinical presentation, exposure history and other diagnostic procedures, including culture, serology, histopathology, and radiographic findings. False-positive results may occur in patients with other fungal infections, including Blastomyces.
Detected: Histoplasma antigen detected. The reportable range of this assay is 0.2 to 25.0 ng/mL. Results should be correlated with clinical presentation, exposure history, and other diagnostic procedures, including culture, serology, histopathology, and radiographic findings. False-positive results may occur in patients with other fungal infections, including Blastomyces.
Detected, >25 ng/mL: Histoplasma antigen detected above the limit of quantification (>25.0 ng/mL). Results should be correlated with clinical presentation, exposure history, and other diagnostic procedures, including culture, serology, histopathology, and radiographic findings. False-positive results may occur in patients with other fungal infections, including Blastomyces.

Interferences and Limitations

Cautions:

Cross-reactivity with other fungal infections, including Blastomyces dermatitidis, may occur. Positive results should be correlated with other clinical and laboratory findings (eg, culture, serology).

Low-level positive titers may persist following resolution of infection and completion of appropriate treatment regimen.

Turbid urine specimens, containing excess protein, cells, or particulate matter, can inhibit the function of the test.

Guidelines

Washington DOH Notifiable Conditions

Ordering & Collection

Specimen Type

Urine

Collection

Collect 5 mL random urine in a sterile, screw-cap container (preservative-free).

Handling Instructions

Outside Laboratories: Transfer 4 mL urine to a sterile, screw-capped vial and refrigerate. Specimen should not be centrifuged.

Stability: Refrigerated (preferred): 14 days; Frozen: 31 days; Ambient: 72 hours.

Reject Due To: gross hemolysis, turbid colored.

Quantity

requested: 4 mL Urine
minimum: 2.5 mL Urine

Processing

Transfer urine to a screw-capped vial and refrigerate. Do not centrifuge.

Sendouts:

Order Mayo test: HSTQU.
Interfaced: Yes.