9
Testing and Clinical Pearls
Culture is diagnostic gold standard; IFN-γ release assay used for screening, and
preferable to tuberculin skin testing due to anerg y
Culture is the gold standard
Culture
Serum agglutination and ELISA; livestock exposure history
Periodic acid–Schiff stain; immunohistochemistry testing ; diarrhea, weight loss, and
joint pains
Culture is the gold standard, but can be difficult; histolog y; PCR
Serologic assay, then repeat in 2 wk; rabbit exposure
Titers >1:256; cat exposure
Serolog y; PCR; livestock exposure
Culture; Aspergillus IgG; histolog y
Culture; urine histoplasma antigen
Culture; histolog y; blasto Ag is nonspecific
Serologic tests using EIA for IgM and IgG; then confirmatory immunodiffusion
Cryptococcal serum antigen
Histolog y; screen with β-D-glucan assay
Granulomas may occasionally be found
Toxoplasma serologic assay IgM and IgG
Serolog y and microscopic visualization of eggs in stool or urine
