Mycology Flashcards
Dermatophytoses diagnosis
10% KOH: septate hyphae
Culture medium for dermatophytoses
Sabouraud’s agar: hyphae and conifia
Spaghetti and meatballs on 10% KOH
Tinea versicolor or an-an
Maladsezia furfur
Treatment for M. furfur
Miconazole
Rose gardener’s disease? Treatment?
Sporotrichosis
Sporothrix schenckii
Tx: itraconazole or potassium iodide
Dimorphic fungus that exists as a MOLD in SOIL and SPHERULE in TISSUE found endemic un Southwestern US and Latin America
Coccidioides immitis
Desert bumbs, influenza-like illness; arthrospores form spherules with endospores with granuloma formation in bones and CNS
Coccidioides immitis
Tx: amphotericin B or itraconazole
If with meningitis: fluconazole
Dimorphic fungus endemic in Ohio and Mississippi River valleys with 2 types of asexual spores: 1) thick walls and fingerlike projections 2) smaller, thin, smooth-walled spores - infective stage
Histoplasma capsulatum
1) tuberculare macronidia
2) micronidia
H. capsulatum grows in soil with
Bird droppings (starlings) or bat guano
Mimickers of tuberculosis
Histoplasmosis - H. capsulatum Paragonimus westermani (parasite)
DOC for H. capsulatum
Amphotericin B or itraconazole
Meningitis: fluconazole
Round yeast with broad-based bud transmitted by inhalation of conidia and the most common cause of fungal pneumonia
Blastomyces dermatitidis
Tx: iraconazole
Thick yeast with multiple buds in wheel configuration (Mariner’s wheel) restricted to Central and South America
Paracoccidioides brasiliensis
Tx: itraconazole
“Man-hater fungus” - only affects men because estrogen inhibits its growth
Paracoccidioides brasiliensis
Lutz-splendore-de Ameida disease
Paracoccidioides brasiliensis
Opportunistic mycoses (4) and protozoan (1)
Candida albicans Cryptococcus neoformans Aspergillus fumigatus Rhizopus oryzae and Mucor spp Pneumocystis jirovecii (protozoan)
Tx for candida in the ff: 1) oropharyngeal and esophageal, 2) skin, 3) disseminated infections, 4) chemoprophylaxis
1) nystatin swish and swallow
2) clotrimoxazole
3) amphotericin B
4) fluconazole
Oval yeast with narrow-based bud surrounded by a wide polysaccharide capsule seen in India inj preparation
Crytococcus neoformans
DOC: amphotericin B and fluconazole
Chemoprophylaxis: fluconazole
Molds with a septate hyphae that form v-shaped branches (acute angles)
Aspergillus fumigatus
Tx: amphotericin B
Saprophytic molds with nonseptate hyphae with walls and branches at right angles; assoc with rhino-orbital-cerebral infection with eschar formation
Mucormycosis
Seen in patients with diabetic ketoacidosis, burns, or leukemia
Frothy exudate that blocks oxygen exchange leading to a V/Q mismatch –> respiratory distress syndrome; most common AIDS-defining illness
Pneumocystis jirovecii
DOC: TMP-SMX
Diagnosis of P. jirovecii
Staining BAL washings: toluidine blue, methenamine silver stain
Infection of this microorganism occurs when CD4
P. jirovecii
P. jirovecii on CXR
Diffuse interstitial pneumonia with ground glass infiltrates bilaterally
3 important dermatophytoses
Microsporum canis
Trichophyton tonsurans
Epidermophyton floccosum
