Laboratory Diagnostics Flashcards
Blood and BM
PPF(possible pathogenic fungi) H. Capsulatum C. Neoformans C. Albicans Blastomyces dermatitidis
Incubation period for spx
Normal specimen- 4 degrees celsius
Blood and CSF - 30-37 degrees celsius
Dermatologic specimens - 15-30 degrees celsius
CSF
C. Neoformans
Coccidioides immitis
Candida, H. Capsulatum, Nocardia and Actinomyces
Collection notes for sterile specimen
Blood- wrights and giemsa stain bottles, india ink or dags test for cryptococcus; with 5-20 ml broth
Marrow- .5 ml with heparinized ac
CSF- sterile tubes, more than two ml is centrifuged with membrane filtration, sediment is examined. Less than two ml, smears are done.
Collection notes for cutaneous specimen
Hair- sterile forceps, scaly ones are selected or those that fluoresce
Nails- cleaned before collection, discolored or HYPERKERATOTIC areas are examined.
Skin- outer edge of ring is scraped for an active infection
Cloramphenicol and cyclohexamide attributes
Cloramphenicol- inhibitory for most bacteria
Cyclohexamide- antifungal, inhibits candida, c. Neoformans and aspergillus
Growth rate
H capsulatum- 10-12 weeks
Rapid growers- within 2 weeks
Candida- 24-72 hours
Normal growers- within 4 weeks
Suitable for systemic mycoses
Brain heart infusion agar
Blood and bm primary collection media
BHI biphasic culture bottles
For dermatophytes, primary isolation media
Dermatophyte test media, Mycosel and mycobiotic agar
Potato dextrose agar differentiates
Trychophyton rubrum( red)
Urea agar is for; and differentiates
C. Neoformans; T. Metangrophytes and T. Rubrum
Rice medium isolates
M. Audouinii
Cottonseed agar isolates
Blastomyces dermatitidis
Nitrate reduction medium
C neoformans
