Basic Mycology (2) Fungal infections form granulomata in response to cell-mediated Acute suppuration occurs in some Fungi have no endotoxin or A cell-mediated positive skin test indicates past exposure to fungal infection (not current infection).

@ A negative skin test indicates no fungal infection unless the patient is Intact skin is a defense against Skin fatty acids & puberty hormones inhibit skin Flora on skin & mucous membranes suppress fungi (e.g.Staph. epidermidis).

@ If normal flora is killed by long-term antibiotics, overgrowth of fungi In respiratory tract, host defenses are the mucous membranes and alveolar IgG & IgM produced are not Cell-mediated immunity is protective.

LABORATORY DIAGNOSIS 4 methods for diagnosis : (1) Direct microscopy, (2) Culture of organism, (3) DNA probe tests, (4) Serological tests.

Direct Depends on finding spores, hyphae, or yeasts under light Specimen is either treated with 10% KOH, or stained with special fungal stains, e.g. * India ink stain to detect capsules. * fluorescent dye stain to identify fungi in tissues

DNA probes tests To identify rapidly fungal colonies in culture before seen visually. Culture Sabouraud's agar, inhibits bacterial growth by its low pH & added antibiotics. Fungi are identified by their mycelia and spores

Using C.F.T., & Latex agglutination test, A significant rise in antibody titer confirms diagnosis