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Compendium Microbiology > Mycology > Flashcards

Mycology Flashcards

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1
Q

Mycology Laboratory Methods

A

Direct examination

  • Calcofluor white
    • fluorochrome
    • binds to cellulose and chitin in fungal cell wall
    • highlights fungi, prototheca, and cysts of acanthamoeba
  • India ink
  • Fontana Mason stains capsule of cryptococcus
  • GMS or PAS in tissue

Fungal culture

  • Brain heart infusion (BHI) agar
  • Sabouraud dextrose agar
  • Inhibitory mold agar
  • above agars incubated at 25-30 degrees for 4-6 weeks
  • Special media:
    • Cottonseed agar converts mold phase of blastomyces to yeast form
    • cornmeal or potato dextrose agar (latter shows pigment form Trichophyton rubrum)
    • cornmeal or rice agar with Tween 80
    • Sabouraud dextrose agar, Dixon medium, or Leeming-Notman medium overlaid with sterile olive oil
    • Trichophyton agars
    • Bird seed (niger seed) agar
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2
Q

Sabouraud dextrose agar (SDA)

  • principle
  • purpose
A
  • Principle
    • Acid pH and high dextrose concentration inhibits bacterial growth but permits growth of fungi; some also contain abx
  • Purpose
    • many fungi
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3
Q

Inhibitory mold agar (IMA)

  • principle
  • purpose
A
  • Principle
    • chloramphenicol and sometimes gentamicin or ciprofloxacin to suppress bacteria
  • Purpose
    • selective isolation of fungi from specimens that may contain commensal bacterial flora
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4
Q

Brain heart infusion agar (BHI)

  • principle
  • purpose
A
  • Principle
    • brain/meat infusion, peptone and dextrose
    • Chloramphenicol and gentamicin can be added
  • Principle
    • nonselective formulation is general purpose medium used for bacteria, yeasts, and molds
    • when containing abx, it prevents commensal bacterial from growing
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5
Q

Cyclohexamide containing media

  • principle
  • purpose
A
  • Principle
    • inhibits growth of many saprophytic fungi, while permitting growth of most pathogenic fungi
    • chloramphenicol and gentamicin can be added
  • Purpose
    • Selective isolation of slow growing pathogenic fungi that may be overgrown by rapidly growing saprophytic fungi
    • cycloheximide also inhibits growth of C neoformans, Candida, Aspergillus, and other zygomycetes
    • targets dermatophytes or thermally dimorphic fungi
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6
Q

Olive oil overlay on SDA, Dixon medium, or leeming-notman medium

use

A

isolate malassezia

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7
Q

Trichophyton agars

A

differentiate between species of trichophyton

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8
Q

Bird seed agar

A

demonstrate pheno oxidase activity of cryptococcus neoformans

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9
Q

Mold morphology

A
  • Hyaline septate molds
    • surface of colonies may be white or colored
    • reverse side of plate is usually light
    • hyphae with frequent septations
  • Dematiaceous molds: septate molds that make melanin
    • surface and reverse side of plate are both dark
  • Zygomycetes: aseptate or pauciseptate
    • lid lifters
    • may be pigmented, but do not make melanin (reverse side is light)
  • Dimorphic fungi: septate hyphae at 25-30 degrees; yeast when reincubated at 37 degrees
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10
Q

Yeast gross morphology and classification

A
  • creamy or mucoid (cryptococcus) colonies; molds make fuzzy colonies
  • candida albicans form “feet” starlike projections
  • further classified by MALDI or by special yeast agar
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11
Q

Yeasts with blastoconidia only

A

Cryptococcus

Candida glabrata

Rhodotorula

Malassezia

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12
Q

Yeasts with blastoconidia and pseudohyphae

A

Candida (except glabrata)

Saccharomyces cerevisiae

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13
Q

Yeast with arthroconidia

A

Trichosporon

Geotrichum

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14
Q

Hyaline molds

A

Hyphae and other structures are nonmelanized

  1. aspergillus
  2. penicillium
  3. fusarium
  4. dermatophytes
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15
Q

Dematiaceous molds

A

Alternaria

P boydii/S boydii

Scedosporium prolificans

Curvularia

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16
Q

Mold with pauciseptate hyphae

A

Zygomycetes (rhizopus, mucor, cunninghamella, rhizomucor)

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17
Q

Thermally dimorphic fungi

A

Histoplasma

Blastomyces

Coccidioides

paracoccidioides

sporothrix

penicillium marnefii

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18
Q

Histoplasma capsulatum

  • diagnosis
  • culture
  • geographic distribution
  • transmission
  • appearance in tissue
A

Diagnosis and culture

  • 2-4 um ovoid yeast with narrow based budding
  • in histiocytes
  • slow growing cottony white mold
  • septated hyaline hyphae with intermittent microconidia and large spiny macroconidia
  • undergo yeast conversion at 37 degrees

Ohio and Missippi river valleys, Latin America, and Spain

Primary infection is pulmonary, can be disseminated (reticuloendothelial); sclerosing mediastinitus

Transmitted via droppings from chickens or bats

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19
Q

Histoplasma duboisii

  • geography
  • disease
  • culture
  • tissue
A
  • Africa
  • local or disseminated (skin, soft tissue, bone)
  • Colony and microscopic morphology indistinguishable from var capsulatum
  • often intraceullar within giant cells
  • round to oval, thick walled yeast, narrow based budding (unlike B dermatitidis which is a similar size)
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20
Q

Blastomyces dermatitidis

  • diagnosis
  • culture
  • disease
  • similar morphology to ___
  • geographic distribution
  • transmission
A
  • uniform, large yeasts (8-15 um) with broad based budding
  • thick wall and double contoured yeast
  • Slow growing mold with cottony white surface that darkens to tan with age at 25-30 degrees
  • septate hyaline hyphae with short, unbranched conidiophores producing single, pyriform to round, smooth conidia (lollipops)
  • Morphology similar to nondimorphic mold Chrysosporium
  • Conversion to yeast at 37 degrees
  • Mississipppi and Ohio River valleys; also in southeastern US and around Great Lakes
  • soil, inhaled
  • pulmonary primary infection
  • disseminated infection affects skin, mucous membranes, and bone
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21
Q

Coccidioides immitis/posadasii

  • morphology
  • resemble ___
  • yeast conversion?
  • geographic distribution
  • transmission
  • disease
A
  • large spherules with thick walls that contain hundreds of endospores
  • 25-30 degrees grows as moist gray colonies that become white and cottony as they mature
  • thin, hyaline septate hyphae and arthroconidia; mature arthroconidia are barrel shaped, and alternate with empty cells
  • Immature arthroconidia resemble Malbranchea
  • difficult yeast conversion
  • San Joaquin Valley California (C posadasii in southwest)
  • soil inhaled
  • Can be easily inhaled by lab personel (be careful!)
  • primary infection is pulmonary
  • disseminated infection affects skin and bone and joints
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22
Q

paracoccidioides brasiliensis

  • morphology
  • gross
  • yeast conversion
  • geographic distribution
  • disease
A
  • round, large yeast with circumferential budding
  • 25-30 degrees: slow growing mold with a white to tan surface
  • hyaline septate hyphae with terminal and intercalary chlamydospores and infrequent pear shaped microconidia arranged along hyphae
  • converts to yeast at 37 degrees
  • Central and South American rain forest
  • primary infection is pulmonary
  • Can disseminate: skin, mucosa, reticuloendothelial
  • Behaves like blastomyces
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23
Q

Sporothrix schenkii

  • morphology
  • geographic distribution
  • transmission
  • disease
A
  • 4-6 um, cigar shaped yeast with narrow based budding
  • 25-30 degrees: grows rapidly into moist, white to pale orange colonies that turn brown with age
  • delicate hyaline septate hyphae producing conidiophores topped by clusters of microconidia (rosettes or daisies)
  • converts to yeast at 37 degrees (cigars with narrow based buds)
  • worldwide distribution
  • acquired by penetrating injury from contaminated plant (rose garden)
  • Alcoholics known to become infected through inhalation
  • lymphocutaneous infection with nodular, ulcerative lesions following lymphatics
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24
Q

Penicillium marneffei

  • appearance of clinical sample
  • culture
  • disease; geographic distribution
A
  • 3-5 um yeast divide by fission in clinical sample
  • Culture
    • 25-30 degrees: rapidly growing tan colonies initially powdery or velvety on the surface, and become colored with maturity (blue/green centrally)
    • red pigment diffuses into agar around colonies
    • hyaline septate hyphae with conidiophores and metulae producing brushlike clusters of phialides
    • converts to yeast at 37 degrees (3-5 um), oval
    • penicilliosis: endemic in southeast Asia
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25
Q

Aspergillus species

  • clinical specimens appearance
  • culture appearance
A
  • clinical
    • hyaline, septate hyphae with 45 degree branching
    • fruiting heads in air filled tissue pockets
  • Culture:
    • rapidly growing; identified by colony morphology and microscopic appearance of swollen vesicle at ends of conidiophores
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26
Q

Culture appearance of aspergillus fumigatus

A
  • blue green with white apron and light reverse
  • conidiophores terminate in a swollen vesicle having a single row of phialides that cover only the top 2/3 of the vesicle
  • each phialide gives rise to chain of small conidia
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27
Q

Culture appearance of aspergillus flavus

A
  • yellow green to olive with light reverse; lateral striations
  • circumferential phialides
  • some strains uniseriate (single row of phialides) or biseriate
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48
Q

Aspergillus niger morphology

A
  • Dark brown to black colonies with light reverse
  • vesicles with 2 rows of phialides (biseriate) covering the entire vesicle
  • phialides produce chains of rough, round, dark conidia
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49
Q

Aspergillus terreus morphology

A
  • colonies are cinnamon brown on the surface with a yellow or orange reverse
  • phialides cover top 2/3 of vesicle , but unlike fumigatus are biseriate and have longer chains of conidia
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50
Q

Diagnosis of aspergillus

A
  • Culture
  • ELISA for serum marker galactomannan and/or 1-3-beta-D-glucan
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51
Q

Aspergillosis

  • transmission
  • clinical disease
  • clinical features of A flavus, A niger, and A terreus
A
  • Ubiquitous in soil and on decaying vegetables
  • Respiratory tract affected
    • Immunocompetent host will have cavitary lung disease: aspergilloma (fungus ball); most commonly caused by A fumigatus
    • Atopic host: allergic bronchopulmonary aspergillosis (ABPA) or allergic sinonasal aspergillosis (allergic fungal sinusitis)
    • Immunosuppressed host: invasive bronchopulmonary aspergillosis (IBPA) or invasive fungal sinusitis, with angioinvasive growth (Aspergillus species and zygomycetes have capacity to invade vessel walls)
  • A flavus produces aflatoxins in food, carcinogens for HCC
  • A niger pulmonary infection associated with oxalosis (calcium oxalate tissue deposition); most common aspergillus associated with otitis externa
  • A terreus resistant to amphotericin B
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52
Q

Fusarium infections

A

similar to aspergillus + fungal keratitis and opportunistic infection in burn wounds

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53
Q

Pseudallescheria boydii/Scedosporium boydii disease

  • transmission
  • diseases
  • treatment
A
  • most common cause of eumycotic mycetoma after penetrating trauma
  • fungal keratitis
  • pneumonia after near drowning accidents
  • P boydii/S boydii resistant to amphotericin B
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54
Q

Conidia arranged in clusters

A

Fusarium

  • canoe shaped
  • multicellular macroconidia with 3-6 cells each

Acremonium

  • long, threadlike, unbranched phialides bearing clusters of single celled microconidia

Gliocladium

  • branching conidiophores bearing flask shaped phialides, resembling Penicillium; microconidia cluster in a ball (golfball at end of finger tip)
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55
Q

Conidia arising in chains

A

Penicillium

  • brushlike arrangement of flask shaped phialides that give rise to unbranching chains of microconidia

Paecilomyces

  • Branching conidiophores with elongated, flask shaped phialides arranged in pairs or brushlike groups
  • long chains of oval or spindle shaped microconidia bend away from the phialides
  • colonies are yellowish brown or pinkish mauve, white, or yellow-green, but are never bright green or blue-green

Scopulariopsis

  • single or branched conidiophores that give rise to annellides (similar to phialides)
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56
Q

Conidia arranged singly

A

Chrysosporium

  • single, cutoff microconidia directly on hyphae or on the tips of simple conidiophores
  • Looks like blastomyces

Sepedonium

  • singly borne, hyaline conidia at the ends of branched or unbranched conidiophores
  • conidia are large, thick walled and echinulate (spiny), resembling macroconidia of mold form of H capsulatum

Beuveria

  • single, small, round or oval microconidia emerging from each inflection point in a zigzagging (geniculate) flask shaped conidiophore
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57
Q

Dermatophytes are grown on what medium?

A

cycloheximide

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58
Q

Diagnosis of dermatophytes

A
  1. KOH prep or calcofluor white prep of skin scrapings
  2. Species ID by colony morphology (trichophyton rubrum produce red pigment on reverse)
  3. Species ID by microscopic examination of conidia
  • Trichophyton rubrum:
    • Tear shaped microconidia along hyphae: “birds on a telephone wire”
  • Trichophyton mentagrophytes:
    • microconidia are arranged in clusters
    • spiral hyphae
    • cigar shaped macroconidia
    • can penetrate hair shafts, unlike T rubrum
  • Trichophyton tonsurans: microconidia have marked variability in size and shape; scalp ringworm
  • Microsporum canis:
    • Macroconidia are spindle shaped and rough (echinulate) and pointed
    • Macroconidia contain > 6 cells separated by transverse septae
  • Microsporum gypseum:
    • Macroconidia are oval with rounded ends unlike M canis and have transverse septae
    • Macroconidia contain less than 6 cells
    • Microconidia also present
  • Epidermophyton floccosum:
    • Macroconidia are smooth, club shaped found singly or in clusters
    • Macroconidia contains 2-6 cells, separated by transverse septae
    • No microconidia
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59
Q
A

Microsporum canis

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60
Q
A

Trichophyton mentagrophytes

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61
Q
A

trichophyton tonsurans

62
Q
A

microsporum gypseum

63
Q
A

epidermophyton floccosum

64
Q

Why are dematiaceous molds pigmented on surface and reverse of plate?

A

both hyphae and conidia are melanized (however, some only melanize one or the other)

65
Q

Fast growing dematiaceous molds with conidia with transverse septae

A

Bipolaris

oval dark conidia (3-5 septations) arising from bent conidiophores; germ tubes at both ends

Dreschslera

similar to bipolaris but lacks bipolar germ tubes in saline incubation; instead germ tubes are along sides of the conidia

Excerohilum

resembles bipolaris but its conidia are longer and thinner and have 5-12 septations

Helminthosporum

bottle brushlike microscopic appearance, with side by side conidia arranged in whorls along conidiophores

Curvularia

Transverely septated conidia curve distinctly when mature

66
Q

Dematiaceous molds- fast growers: conidia with transverse and longitudinal septae

A

Alternaria

chains of muriform (brick wall) conidia that have alternating blunt and pointed ends

Ulocladium

oval muriform conidia borne singly on bent conidiophores

Stemphilium

Resembles ulocladium but borne upon straight condiophores

67
Q
A

bipolaris

68
Q
A

drechslera

69
Q
A

excerohilum

70
Q
A

Helminthosporium

71
Q
A

Curvularia

72
Q
A

Alternaria

73
Q
A

ulocladium

74
Q
A

Stemphilium

75
Q

Slow growing dematiaceous molds

  • early growth is yeast like becoming mold like with age
  • always look mold like
A

Early yeast like, mold like later

  • exophiala
  • wangiella
  • hortaea

Always mold like

  • pseudoallescheria boydii/scedosporium boydii complex
  • scedosporium prolificans
76
Q

Pseudallescheria boydii/ scedosporium boydii

  • colonies
  • sexual versus asexual forms
  • treatment
A
  • light gray or brown surface, owing to melanization of its oval, truncated microconidia
  • hyphae are hyaline (nonmelanized) creating a light reverse
  • produces large dark cleistothecia in sexual state
  • asexual form lacks cleistothecia
  • alternative asexual form (graphium) has mats of long conidiophores stuck together side by side, resembling the bristles of a broom
  • resistant to amphotericin B, but susceptible to triazoles
77
Q

Scedosporium prolificans

  • colonies
  • differences from P boydii
  • micro
  • treatment
A
  • gray or black surface and reverse (dematiaceous)
  • unlike P boydii its growth is inhibited by cycloheximide and it has no sexual state
  • microconidia are oval and truncated, forming clusters at the end of annellides (conidiogenous cells)
  • annellides have swollen bases and thin necks
  • resistant to amphotericin B, azoles and echinocandins (so antifungal therapy is ineffective)
78
Q

Clinical features of dematiaceous molds

A
  1. Chromoblastomycosis
    • subcutaneous mycosis associated with prominent pseudoepitheliomatous hyperplasia
    • tissue shows pigmented hyphae and sclerotic (muriform) bodies
    • Organisms:
      • fonsecaea pedroi
      • phialophora verrucosa
      • cladophialophora carrionii
    • tropical and subtropical
    • gain entrance through puncture wounds, lower extremities
  2. Mycetoma (Madura foot or maduromycosis)
    • subcutaneous infection with draining sinus tracts
    • can be caused by bacteria (actinomycotic mycetoma) or molds (eumycotic mycetoma)
    • subcutaneous nodule contains granules (mold with a proteinaceous matrix)
    • usually from puncture wound
    • Organisms:
      • Madurella
      • exophiala
      • wangiella
      • P boydii/S boydii
      • actinomycotic: aerobic actinomycetes (nocardia)
  3. Phaeohyphomycosis: do not fit into the above categories
79
Q

Zygomycetes

  • diagnosis in clinical specimens
  • culture (growth rate, list species)
  • define zygophore
A
  • clinical specimens have broad, hyphae with few septations and few branches; nondichotomous
  • Rapid growth in culture
  • Zygophore is a diploid reproductive stage in the life cycle; defining zygomycetes
  • Species
    • Rhizopus
    • Mucor
    • Lichtheimia (formerly Absidia)
    • Cunninghamella
80
Q

Characteristics of rhizopus organisms

A
  • rhizoids and unbranched sporangiophores that arise directly from rhizoids
  • sporangia are spherical and full of spores that collapse when mature (like a collapsed umbrella)
  • sporangiophores lack an apophysis
81
Q

Mucor species

A
  • do not produce rhizoids
  • sporangiophores are branched or unbranched, but lack apophysis
  • sporangia are spherical and fall apart, releasing spores
82
Q

Lichtheimia species

A
  • has rhizoids but sporangiophores arise at points between rhizoids rather than over rhizoids
  • sporangiophores are branched and form a conical apophysis at the top
83
Q

Cunninghamella species

A
  • branched sporangiophores topped by large vesicles
  • vesicles covered by spines (denticles), which supports a single spore contained within a round sporaniolum
84
Q

Clinical features of zygomycetes

A
  • several forms of invasive infection
    • rhinocerebral
    • pulmonary
    • GI
    • cutaneous
  • hosts often immunocompromised
  • risk factors
    • DM (esp ketoacidosis)
    • stem cell or solid organ transplant
    • neutropenia
    • corticosteroid therapy
    • severe burns
  • invade vessel walls (like aspergillus)
85
Q
A

cunninghamella

86
Q

Chromagar

A

agar plates that are selective for yeast allowing for some differentiation between some Candida species on basis of color

87
Q

Germ tube test

A
  • yeast incubated in serum at 37 degrees for up to 3 hours
  • wet mount is made and examined for germ tubes (hyphae with no constriction at the juncture with the yeast cell)
  • C albicans and dubliniensis make true hyphae without constriction (germ tubes) (most candida species do not make germ tubes)
88
Q

Rapid treholase assimilation

A

Presumptively identify C glabrata

  • yeast isolate is inoculated into broth containing treholase and a pH indicator
  • after 3 hour incubation at 42 degrees fermentation of the substrate causes a color change
89
Q

Urease test, fungi

A

Presumptively identify Cryptococcus

  • urease activity distinquishes ascomycetous yeasts (no urease activity) from basidiomycetous yeasts (urease activity)
  • urease disks detect urease activity by a color change within a few hours; somewhat longer testing needed for urea agar slants
  • common basidiomycetous yeasts: rhodotorula and trichosporon
90
Q

Phenol oxidase test, fungi

A

Presumptive identification of C neoformans

  • C neoformans oxidizes diphenolic compounds such as caffeic acid, dopamine, and dopa to produce darkly pigmented melanin or melanin precursors
  • culture yeast on bird seed agar (which has caffeic acid)…if brown colonies grow, it is C neoformans
  • Rapid method involves use of caffeic acid disks inoculated with yeast isolate and can demonstrate brown pigment production within a few hours
91
Q

Definitive identification of yeasts

A
  1. biochemical tests
  2. MALDI-TOF
  3. demonstration of specific morphology with specialized media
  4. rice or cornmeal agar supplemented with Tween 80 will induce formation of blastoconidia, pseudohyphae, true hyphae, arthroconidia or chlamydospores
92
Q

C albicans

  • clinical significance
  • morphology (micro and colonies)
  • tests
  • treatment
A
  • most common candida species isolated from humans
  • 3-5 um budding yeast with pseudohyphae and occasional true hyphae
  • have feet on agar (not seen in non-albicans species)
  • when cultured on cornmeal or rice agar with Tween it forms pseudohyphae with clusters of blastoconidia at septations, as well as terminal chlamydospores
  • positive germ tube test
  • forms green colonies on chromogenic agar
  • most susceptible to azoles, echinocandins, and amphotericin B
93
Q

C glabrata

  • clinical specimens
  • morphology
  • growth rate
  • culture characterstics
  • other tests
  • treatment
A
  • isolated from blood and urine
  • 2-4 um budding yeast (blastoconidia), without pseudohyphae
  • grow more slowly than other candida species
  • yeast morphology medium does not induce structures other than budding yeast
  • positive trehalose test
  • reduced susceptibilty to azoles but most are susceptible to echinocandins and amphotericin B
94
Q

Cryptococcus species

  • human pathogens
  • geographic distribution
  • size
  • transmission
  • morphology
  • tests
A
  • C neoformans and C gatii are the most common pathogens in the US and tropical zones/northwest, respectively
  • Inhalation of soil
    • C neoformans: soil containing bird excreta (pigeon, chicken)
    • C gatti: eucalyptus trees
  • 3-15 um narrow budding yeast
  • encapsulated
  • cell walls contain melanin
  • Colonies often mucoid
  • Never forms other structures like pseudohyphae
  • Phenol oxidase test
  • Cryptococcal capsular polysaccharide antigen can be detected in either serum or body fluids (CSF)
95
Q

Pneumocystis jiroveci

  • culture
  • diagnosis
  • diseases
  • serum markers
  • stains
A
  • cannot culture in vitro
  • diagnosis depends on direct examination of clinical specimen
  • disease in HIV with CD4 < 200 cells/ml
  • disease also occurs in SCID, chemo (esp lymphoma), transplanted or collagen vascular disease patients
  • LDH high
  • serology not helpful
  • Respiratory sample: exudate
  • Giemsa, PAS, GMS stain orgs
  • Immunofluorescent staining wtih antibodies also work
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125
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Colony colors:

Coccidioides

Blastomycosis

Paracoccidioides

Sporothrix

Penicillium marnefii

A flavus

A fumigatus

A terreus

Trichophyton rubrum

A
  • Coccidioides: moist gray turns cottony white
  • Blastomycosis: Cottony white turns tan
  • Paracoccidioides: white-tan
  • Sporothrix: pale orange turns brown
  • Penicillium marnefii: powdery tan turns blue/green centrally with surrounding red
  • A flavus: yellow-green
  • A fumigatus: dark blue-green with white apron
  • A terreus: cinnamon brown with yellow-orange reverse
  • Trichophyton rubrum: red reverse
126
Q
A

Ulocladium

(usually a contaminant)

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A
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Scedosporium prolificans

  • invasive infection with arthritis or osteomyelitis
  • growth inhibited by cyclohexamide
131
Q
A

Bipolaris

  • fast growing dematiaceous mold
  • allergic sinusitis
  • brain lesions in IC
132
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A

Exserohilum

  • fast growing dematiaceous mold
  • phaeohyphomycosis in nasal sinuses, skin, subcutis, cornea
133
Q
A

Helminthosporium

  • fast growing dematiceous mold
  • contaminant
134
Q
A

Curvularia

  • fast growing dematiaceous mold
  • cornea and sinus opportunistic infection
  • mycetoma
  • phaeohyphomycosis
135
Q
A

Alternaria

  • fast growing dematiaceous mold
  • usually a contaminant
136
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A

Stemphylium

  • contaminant
137
Q
A

Chrysosporium

causes adiaspiromycosis, a granulomatous infection with large thick-walled spherules

138
Q
A

Sepedonium

  • contaminant
  • differs from H capsulatum by
    1. not forming yeast at 37 degrees
    2. not forming microconidia
139
Q
A

Beauveria bassiana

  • contaminant
140
Q
A

Fusarium

141
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A

Gliocladium

  • contaminant
142
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A

Acremonium

  • white grain mycetoma
143
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A

Penicillium

  • contaminant
  • corneal, cutaneous, external ear, respiratory, and UTIs, and endocarditis with prosthesis
144
Q
A

Paecilomyces

145
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A

Scopulariopsis

146
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A

Microsporum canis

  • scalp and skin infections, occasionally nails
  • kids acquire infection from dogs and cats
147
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A

Microsporum gypseum

  • scalp and skin
148
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A

Trichophyton rubrum

  • skin and nails and only rarely hair
  • one of the more common causes of onychomycosis
  • most frequently isolated dermatophyte infecting humans
149
Q
A

Trichophyton mentagrophytes

  • invades all parts of body surface
  • athlete’s foot
150
Q
A

Trichophyton tonsurans

  • scalp ringworm
  • skin and nails infected also
151
Q
A

Epidermophyton floccosum

  • skin and nail infection (not hair)
152
Q
A

Penicillium marneffei PDA

Penicillium marneffei SDA

Compendium Microbiology (15 decks)

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