Members of the plant kingdom
Lack of roots and stems
Lack chlorophyll
Fungi
Coenocytic hyphae
Aseptate hyphae
Type of mycoses produce no cellular response by the host
Superficial mycoses
Arthroconidia on the outside of the hair as well hyphae within the hair shaft
Ectothrix
True yeast produce what in the asexual stage
Blastoconidia
Septate hyphae have
Divisions
Molds with aseptate hyphae produced a specialized hyphal structure called
Sporangiospore
Basic, branching, intertwining structures of molds
Mycelium
Arthroconidia are formed
directly from hyphae by fragmentation
Mycelia within the colony that grow into the substrate are called
Vegetative hyphae
Chlamydospores that grow within the hyphae
Intercalary
Budding forms in which the daughter cell forms as a bud from a single mother cell or forms laterally from a mycelium or pseudo mycelium
Blastospores
Result of asexual production
Ascospores
Conidia are
Asexual spores
Macroconidia are usually
Multicellular
Swollen portion of the conidiophore is called
Vesicle
NOT apply to true yeast
They exhibit thermal dimorphism
Conidia with rough spiny surfaces are described as
Echinulate
Conidia in chains are said to be
Catenate
When preparing temporary mounts of fungal elements, why is the slide gently heated?
Increase the rate of clearing
Acts as a clearing agent to eliminate debris and make fungal elements more prominent in skin, hair, nails
10% KOH
Stain in Aman medium
Cotton blue
In the Periodic Acid Schiff stain (PAS), what colors denote the presence of GLYCOGEN
Red to violet
Stain used for delineation of fungal elements by fluorescent microscopy
Calcofluor white
When the fungus wall is invinsible with the Hematoxylin and Eosin stain, which of the following may be used to restain the slide
Periodic acid Schiff stain
Color of FUNGAL elements in acridine orange staining procedure
Fluoresces a green color
How does Mycosel medium differ from Sabouraud dextrose agar
Contains chlorampenicol and cycloheximide
Fungus medium used for the primary isolation and maintainance of fungal cultures
Sabouraud Dextrose Agar
Indcator in Dermatophyte Test Medium
Phenol Red
If 1% glucose is added to cornmeal agar, Trichopython rubrum can be differentiated from Trichophyton mentagrophytes by the production of
Pigment
Fungi shoul be incubated at
25-30 C
How long should fungus cultures be held before reporting as negative
30 days
Antibiotics added to media for the isolation of pathogenic fungi from contaminated material
Cycloheximide and chlorampenicol
Media stimulates the production of chlamydospores
Cornmeal agar
Media identifies species of aspergillus
Czapek’s agar
Positive resul in the hair baiting test
V-shaped penetration of the hair shaft
Tinea infection is commonly referred to as
Ringworm
Organism that cause white piedra
Trichosporon beigelii
Tinea unguinum is a dermatophyte infection of the
Nail plates
The favus type of Tinea capitis is caused by
Trichophyton schoenleinii
Anthrophilic
Microsporon audouni
Hairs infected with which of these dermatophytes fluoresce under Wood’s lamp
Microsporum canis
Colonization by dermatophytic fungi of the hair, nails and skin is called
Dermatophytoses
Fungi that cause dermatophytoses
Epidermophyton
Trichophyton
Microsporum
Produces macroconidia that are large, multicellular and club shaped with smooth walls
Epidermophyton floccosum
NOT true
T. rubrum is noted for its balloon forms
Produces small, vey slow growing colonies and has favic chandeliers
Trichophyton schoenleinii
Diagnostic for chromoblastomycosis
Sclerotic body
Found in yeast phase of Sporothrix schenckii on culture medium at 37 C
Cigar shaped yeast cells
Result of an antigen-antibody reaction in cases of sporotrichosis
Asteroid body
In older mold cultures of Sporothrix schenckii, single conidia borne along the sides of hyphae are referred as
Sleeve
Infections that is caused by dermatiaceous saprobes that invade organs of immunosuppressed host
Phaeohyphomycosis
Most common cause of mycetoma (maduramycosis) in the US
Pseudoallescheria boydii
Dermatiaceous fungi have colonies with
Surface and reverse side dark
Dermatiaceous fungi
Phialophora and Cladosporium
Sclerotic bodies are found in tissue in an infection with
Cladosporium
NOT cause infection of chromoblastomycosis
Exophiala
Fungus that grows as a mold at 35-37 C and at 25 C
Monomorphic
True fungi that produce hyphae and spore forms
Eumycotic
Causes an infection by hyaline saprobes that invade most tissues or body fluids of immunosuppresed host
Aspergillus
Penicillium marneffei
Fusarium moniliforme
If you observe cleistothecia containing ascospores, report organism as
Pseudoallescheria boydii
Actinomyces are best classified as
Fungus like bacteria
Anaerobic, gram positive but not acid fast and does not stain with fungal stains
Actinomyces israelli
Has a capsule
Cryptococcus neoformans
When culturing Cryptococcus on Sabouraud dextrose agar, what antibiotics should not be in the medium
Cycloheximide
In the direct microscopic examination of CSF, what is mistaken as lymphocyte
Cryptococcus
Why does Cryptococcus neoformans pproduce a brown color on Birdseed or staib agar
Assimilates creatinine
C. neoformans latex agglutination test on spinal fluid detects cryptococcal
Antigen
Candida albicans produces
Blastospores
Chlamydospores
Pseudohyphae
Another name of oral candidiasis
Thrush
Presumptive identification of Candida albicans can be made by checking the ability of the organism to produce
Germ tube
Cornmeal agar plus Tween 80 is used to identify Candida albicans through the organisms production of
Chlamydospores
Geotrichum candidum colonies appear as
Rapid, yeast like growth
Laboratory workers are in no danger when handling which form of dimorphic fungi
Yeast form (tissue)
Sepedonium produces spiny, tuberculate macroconidia but is a
Monomorphic mold
Produced by Geotrichum candidum
Rectangular, evenly staining arthroconidia
Dimorphic fungi
Histoplasma capsulatum
Blastomyces dermatitidis
Paracoccidioides brasiliensis
Tissue phase of Histoplasma capsulatum characteristically shows
Yeast cells within macrophages
Characteristic structures of the mycelial phase of Histoplasma capsulatum are
Tuberculate chlamydospores
Leishmania can be differentiated from Histoplasma because Leishmania has
Cental nuclear material
Test that may be sued instead of conversion when identifying dimorphic fungi
Exoantigen test
In the mycelial form, Blastomyces dermatitidis produces
Conidiophores that resemble lollipops
A yeast form with a single broad based bud would identify an organism as
Blastomyces
The characteristic structures of the mycelial phase of blastomycosis are
Small pear shape conidia called lollipops
Yeastlike forms with multiple buds
Paracoccidioides brasiliensis
Immature spherules of Coccidioides are differentiated from yeast forms of Blastomyces because
They never bud
Fungi that is a major biohazard to laboratory personnel
Coccidiodes immitis
Exoantigen test is a
Microscopic immunodiffusion test
In the exoantigen test for Histoplasma capsulatum, which bands are present in a positive result
H and/or M
When differentiating Histoplasma capsulatum from Leishmania using special fungus stains, Leishmania stains
Will not stain
Bands in the Exoantigen test for Blastomyces dermatitidis is present in positive result
A
Fungi produces a spherule that is filled with endospores
Coccidiodes immitis
Zygomycosis is caused by
Mucor
Rhizopus
Fungal elements in zygomycosis show hyphae that are
Broad and nonseptate
A mature virus particle containing a nucleic acid surrounded by protein coat, with or without envelope is called a
Virion
Viruses are characterized by the presence of
DNA and RNA
Largest DNA virus
Poxvirus
Smallest RNA virus
Enterovirus
First step in the replication of cycle of a virus
Attachment and Penetration
The virus capsid morphology is
Helical or icosahedral
From what part of the virus is the envelope acquired
Nuclear or cytoplasmic membrane
Where is the site of virion assembly
Nucleus or cytoplasm
DNA virus
Herpesviridae
RNA virus
Pseudomyxoviridae
Specimens collected for virus isolation should be kept at
4 C
Transport temperature of viruses
- 70 C
In what family of viruses, after primary infection, does an individual become latently infected and then the infection can be reactivated
Herpesviridae
Cytomegalovirus isolation is best accomplished using
Human emryonic fibroblasts
Virus causes acute acute central nervous system disease in humans and animals
Rabies
Specimens should be collected from a patient with suspected enteroviral meningitis
Stool
Throat swab
CSF
Influenza A viruses can be detected in cell cultures by
Hemadsorption assay
The best host system for influenza virus isolation are
Monkey kidney cells
Embryonated hen’s egg
What common antigen is cross reactive in all human adenoviruses
Hexon
NOT characteristics similar to both influenza and parainfluenza
Segmented RNA genome
Myxoviridae virus envelope contains both
Neuraminidase and hemagglutinin
Eosinophilic cytoplasmic inclusions are elementary bodies of the
Poxvirus
Geman Measles is caused by
Rubella virus
Mild form of small pox
Alastrim
Laboratory procedures that is routinely used for the detection of Hepatitis B virus (HBV) in blood donors
Solid phase RIA
ELISA
Most raapid mtd for diagnosis of a virus infection
Direct electron microscopy
Specimen collected from a patient with suspected influenza
Throat swab
Virus group contains a double stranded, segmented RNA genome
Reovirus
Enteroviruses can be differentiared from rhinoviruses by
Acid resistance
Virus most frequent cause of gastroenteritis in children during the winter months
Rotavirus
NOT resistant to ether treatment
Herpesviruses
Most common method for rapid electron microscopy examination is
Negative staining
Various virus groups can be differentiated in negatively stained specimens by their
Morphology
