The histoplasma antibody immunodiffusion test is used for the in vitro determination of precipitating antibodies to Histoplasma sp. It is also used as an aid in the diagnosis of Histoplasmosis.
This test detects the presence of two significant precipitin bands. Presence of both the H and the M band indicates active histoplasmosis. The presence of the M band alone indicates early or chronic disease. The M band may also be present following a recent histoplasmin skin test.
The result is not intended to be used as the sole means for clinical diagnosis or patient management decisions.
Negative serologic tests may be observed among culturally demonstrable cases, which limits the predictive value of a negative test.
Negative serologic results obtained during the first month may warrant repeat testing.
Falsely negative results may be obtained when testing immunocompromised patients.
Test results cannot be used solely, to distinguish between active infection and prior exposure.
Serum: Collect serum specimens in serum separator or red top tube. Allow blood to clot for 30 minutes, then centrifuge. Pipette serum into a plastic screw cap vial.
Minimum Specimen Requirements
Serum: 0.25 mL per antibody
Refrigerated: 14 days
Frozen: 6 months
Any specimen types other than serum.
Ship on dry ice to arrive Monday‐Friday using a next day delivery service. Frozen ice packs may be substituted if sample is shipped the day of collection.