MTS Mycology

This result of a hair perforation test is typical for which of the following fungi?

Note: select an answer in the list below. Click the Submit button to continue.

Epidermophyton floccosum

Malassezia furfur

Trichosporon beigelii

Trichophyton rubrum

Trichophyton mentagrophytes

Trichophyton mentagrophytes produces hyphal structures that invade hair shafts forming cone-shaped perforations. This is a useful test to differentiate dermatophytes.

This India ink preparation suggest which of the following organisms?

Blastomyces dermatitidis

Candida albicans

Cryptococcus neoformans

Histoplasma capsulatum

Paracoccidioides brasiliensis

Cryptococcus neoformans produces a polysaccharide capsule which is visible in an India ink preparation. India ink preparations can be performed directly on cerebrospinal fluid.

This microscopic image suggests which of the following fungi?

Coccidioides immitis

Histoplasma capsulatum

Phialophora verrucosa

Sporothrix schenckii

Wangiella dermatitidis

In the environment or when cultured on laboratory media, Coccidioides immitis grows as a mold. In this form, it produces hyphae which differentiate into arthroconidia alternating with empty disjunctor cells.

This microscopic image suggests which of the following dermatophytes?

Epidermophyton floccosum

Microsporum canis

Trichophyton mentagrophytes

Trichophyton rubrum

Microsporum canis produces rough, spindle-shaped, thick-walled macroconidia.

This microscopic image suggests which of the following?

Epidermophyton floccosum

Microsporum canis

Trichophyton mentagrophytes

Trichophyton rubrum

Trichophyton tonsurans

Epidermophyton floccosum produces clusters of smooth, club-shaped macroconidia. The cell walls of Epidermophyton are thicker than those of the genus Trichophyton.

This yeast developed at 37ºC. Select the most likely identification.

Blastomyces dermatitidis

Cryptococcus neoformans

Coccidioides immitis

Histoplasma capsulatum

Paracoccidioides brasiliensis

Paracoccidioides brasiliensis is a dimorphic mold that produces yeast with multiple buds at 37ºC.

These macroconidia developed at room temperature. Select the most likely identification.

Blastomyces dermatitidis

Cryptococcus neoformans

Coccidioides immitis

Histoplasma capsulatum

Paracoccidioides brasiliensis

Histoplasma capsulatum produces warty (tuberculate) spherical macroconidia at room temperature.

This yeast developed at 37ºC. Select the most likely identification.

Blastomyces dermatitidis

Cryptococcus neoformans

Coccidioides immitis

Histoplasma capsulatum

Paracoccidiodes brasilensis

At 37ºC, Blastomyces dermatitidis produces broad-based budding yeast cells with thick walls.

This microscopic image suggests which of the following molds?

Aspergillus flavus

Aspergillus fumigatus

Paecilomyces spp.

Penicillium spp.

Scopulariopsis spp.

Penicillium spp. produce clusters of thick phialides bearing chains of round conidia.

This microscopic image suggests which of the following fungi?

Aspergillus flavus

Aspergillus fumigatus

Paecilomyces spp.

Penicillium spp.

Scopulariopsis spp.

Paecilomyces spp. produce widely-spaced, elongated, slender phialides bearing chains of oval conidia.

This microscopic image suggests which of the following molds?

Aspergillus flavus

Aspergillus fumigatus

Paecilomyces spp.

Penicillium spp.

Scopulariopsis spp.

Aspergillus fumigatus produces uniserate phialides bearing chains of round conidia. The phialides are located only on the upper portion of the vesicle.

This microscopic image suggests which of the following molds?

Alternaria

Curvularia

Epicoccum

Pithomyces

Ulocladium

Alternaria spp. are dematiaceous molds that produce chains of racket-shaped muriform poroconidia.

This microscopic image suggests which of the following molds?

Alternaria

Curvularia

Epicoccum

Pithomyces

Ulocladium

Curvularia spp. are dematiaceous molds that produce curved poroconidia with a swollen central cell.

This microscopic image suggests which of the following molds?

Chaetomium spp.

Mucor spp.

Pseudallescheria boydii

Phoma spp.

Rhizopus spp.

Chaetomium spp. produce large fruiting bodies called perithecia. The perithecia are covered with thick hair-like projections called setae and contain oval ascospores.

This microscopic image suggests which of the following molds?

Chaetomium spp.

Mucor spp.

Pseudallescheria boydii

Phoma spp.

Rhizopus spp.

Phoma spp. produce spherical pycnidia containing conidia which are released through an opening called an ostiole.

This microscopic image suggests which of the following molds?

Chaetomium spp.

Mucor spp.

Pseudallescheria boydii

Phoma spp.

Rhizopus spp.

Rhizopus spp. produce sporanigia borne on long sporanigiophores. Rhizoids are produced directly opposite the sporangiophore.

This microscopic image suggests which of the following molds?

Aspergillus flavus

Aspergillus fumigatus

Paecilomyces spp.

Penicillium spp.

Scopulariopsis spp.

Aspergillus flavus produces rows of uni- or biserate phialides bearing chains of round conidia. The phialides are produced on the entire surface of the vesicle.

This microscopic image suggests which of the following organisms?

Blastocystis dermatitidis

Candida albicans

Cryptococcus neoformans

Pneumocystis carinii

Malassezia furfur

Pneumocystis carinii produces round to oval cysts that stain blue with Gram-Weigert.

This microscopic image suggests which of the following molds?

Exophiala jeanselmei

Fonsecaea spp.

Phialophora richardsiae

Phialophora verrucosa

Wangiella dermatitidis

Phialophora verrucosa produces vase-like phialides with cup-shaped collarettes that form oval conidia.

This microscopic image suggests which of the following organisms?

Candida albicans

Malassezia furfur

Microsporum canis

Trichophyton rubrum

Trichosporon beigelii

Malassezia furfur is most often diagnosed from direct examination. Infected skin scrapings show fungal elements with a characteristic "spaghetti and meatball" appearance.