Opportunistic Fungi Flashcards
Mucormycetes
Organisms are widely distributed in soil, dung, and vegetation
Humans become infected through inhalation of air-borne spores or through ingestion of contaminated foodstuffs.
Lichtheimia complex (Absidia) Micro
Aseptate hyphae and wide
Sporangiophores arise at point on stolen that is between the rhizoids
Sporangium is pear shaped
Mucor species Micro
Nonseptate, wide hyphae
Long, simple branched sporangiophores
Large, round, spore filled sporangia
NO RHIZOIDS
Rhizopus species Micro
Broad hyphae with no or few septations
Numerous stolons connect long groups of unbranched sporangiophores
Rhizoids are at point where stolons and sporangiophores meet
Rhizomucor species
Nonseptate, broad hyphae
Rudimentary rhizoids are few in number and located on stolons between sporangiophores
Syncephalastrum species Micro
Nonseptate, broad hyphae
Demonstrates short, branched sporangiosphore with swollen tip
Chains of round spores enclosed in fingerlike tubular sporangia
Cunninghamella species Micro
Broad, nonseptate hyphae
Long, branched sporangiophore ending in swollen vesicle
Vesicles are covered with spine denticles
Circinella species Micro
Mycelium strongly branched, nonseptate
Sporangiophore is erect on mycelium but strongly curved at the tip where sporangium is carried
Aspergillus fumigatus Morph
Granular to cottony
Smoky green, grey-green, or green-brown with white apron
Reverse: Yellow
Thermo tolerant
Aspergillus fumigatus Micro
Septate hyphae
Conidiophores are long and ending in dome-shaped vesicle
Uniserate phialides which cover only upper portion of vesicle
Long chains of round to ovoid conidia
Aspergillus niger Etiology
Swimmer’s ear
Fungus ball
Aspergillus fumigatus
Common cause of fungus ball
Aspergillus niger Morph
Jet black, powdery
Revers: Buff
Aspergillus niger Micro
Septate hyphae
Long conidiophores that have spherical vesicles
Phialides that have long chains of rough, round conidia
Aspergillus flavus Etiology
Sinusitis
Otitis
Invasive disease in granulopenic patients
Aspergillus flavus Morph
Granular to woolly
Yellow-green or yellow-brown
Aspergillus flavus Micro
Septate hyphae
Long conidiophores finely echinulated beneath vesicle
Phialides surround entire circumference of vesicle surface
Conidia are smooth, round
Aspergillus terreus Morph
Powdery
Tan or Cinnamon brown
Reverse: Yellow
Aspergillus terreus Micro
Small Vesicles
Phialides are biserate and cover upper portion of vesicle
Smooth, elliptical conidia form long chains
Aspergillus versicolor
Procudes mycotoxins sterigmatocystin and cyclopiasonic
Toxins cause diarrhea and upset stomach, kidney and liver toxicity
Aspergillus versicolor Morph
Varied in color and range from pale green, to green-beige, pinkish-green, salmon green, or dark green.
Reverse: Colorless to red
Aspergillus versicolor Micro
Septate hyphae
Conidial heads are biserate and loosely radiate from conidial head
Vesicles are small
Reduced conidial structures may resemble Penicillium species
Aspergillus clavatus Etiology
Seldom seen in clinical infections
Implicated in pulmonary infections, endocarditis, otomycosis, and various toxic syndroms
Aspergillus clavatus Morph
Green with white border
Reverse: White to tan
Aspergillus clavatus Micro
Septate hyphae
Phialides are uniseriate and closely packed on surface of extremely large club-shaped vesicle
Conidia are smooth, round
Aspergillus nidulans Etiology
Infectionsin lung, brain, bone, eyes, nasal sinus, and skin
Aspergillus nidulans Morph
Dark green or olive colony with white border
Reverse: Buff, brownish orange or deep reddish purple
Aspergillus nidulans Micro
Septate hyphae
Conidiophores are short, smooth, and biseriate forming on upper half of vesicles
Hulle cells are usually present
Penicillium marneffei Etiology
Cause hematological malignancies with patients who are immunosuppressed
Results in pulmonary infection
Lymphatic system, liver, spleen, and bones are usually involved
Penicillium marneffei Morph
Thermally dimorphic
25 C - colonies are bluiish-grey-green with white apron. Red, rapidly diffusing, soluble pigment observed
37 C - cream colored to slightly pink forming a yeast-like growth with convoluted topology
Penicillium marneffei Micro
Filamentous phase - similar to other Penicillium species
Yeast phase - globose to elongated sausage-shaped cells
