Classification Of Fungi & Fungi Diseases Flashcards
Fungi’s are eukaryotic organisms.
True/ false
True
Fungi are not found everywhere in nature.
True/false
False
How does fungi digest food??
They digest them extracellularly and absorb them from their cell wall.
What is contained in the cell wall of fungi?
Chitin, glucan and other Polysaccharides.
What is contained in the cytoplasmic membrane of fungi?
Ergosterol.
Cholesterol is seen in bacteria cell memberane.
Mode of reproduction of fungi??
Sexually, asexually or both.
What are the two forms of fungi?
Unicellular (yeast), but mainly multicellular (moulds)
The mode of respiration in fungi is?
Obligate or facultative aerobes.
Fungi must grow with light.
True/false
False.. They grow with or without light.
What are the modes of nutrition of a fungi?
Parasitic, saprophytic, heterotrophic
What are the fxns of the fungi cell wall?
Gives the fungi shape and form.
Protects against mechanical injury.
Prevents osmotic lysis.
The site of action of antifungal like capsofungin is?
Beta glucan.
Capsofungin is an echinocandin.
True or false
True.
Ergosterol os the site for antifungal drugs like?
Amphotericin B, azole group.
What are the morphological stages in a fungi?
Vegetative stage.
Reproductive stage.
What kind of structures are the vegetative stage constituted of??
Tender thread like structures called hyphae.
A mycelium is??
An interconnected network of hyphae.
A hyphae can be septate or non septate
True /false
True.
The systems of classification in a fungi include?
Morphological systems.
Systemic classification.
Fungi are classified based on their cellular nature into??
Single celled forms e.g yeast which reproduces by budding.
Multicellular forms e.g moulds which forms multicellular hypae.
Examples of single celled fungi are?
Candida species
Cryptococcus neoformans
Trychosporum spp
Moulds are divided based on their hyphae into?
Septate and aseptate
Examples of aseptate moulds include?
Zygomycetes.
Rhizopus.
Mucor.
Septate moulds are divided into?
Opportunistic.
Dimorphic.
Dermatophytes.
Examples of Dermatophyte fungi include?
Trychphyton.
Microsporon.
Examples of opportunistic moulds include?
Aspergillus.
Fusarium.
Scedosporium.
Examples of Dimorphics include?
Histoplasma
Blastomyces
Penicilum
Based on morphological classification, fungi is divided into?
Yeast
Yeast-like fungi
Filamentous/moulds
Dimorphic
What is the morphological classification of fungi?
Yeast
Yeast-like fungi
Filamentous
Dimorphic
What are moulds?
They are fungi that have/ exist in hyphae form.
What are the examples of moulds?
Dermatophytes
What are yeasts??
Single celled fungi that bud to reproduce.
What are yeast like fungi??
They are fungi that form pseudo hyphae
Examples of yeast?
Cryptococcus neoformans.
Examples of yeast like fungi?
Candida albicans.
What are Dimorphic fungi?
They exist as yeast in tissue and moulds in culture.
The Filamentous form of Dimorphics occurs in what temperature?
25°C
The yeast form of Dimorphics occurs in which temperature?
37°C.
Examples of Dimorphics are??
Blastomyces dermatidis.
Histoplasma capsulatum.
Coccocidiodis immitis.
Paracoccocidiodis brasillensis.
What are the diseases caused by Dimorphics?
Sporotrichosis
Histoplasmosis
Blastomycosis
Coccidiodomycosis
In the systemic classification of fungi, the Phylum is divided based on??
Their sexual spore formation.
The Phylum of fungi is divided into??
Ascomyocota.
Basidiomyocota.
Zygomycota.
Deturomycetes.
Zygomycetes reproduce asexually by producing??
Sporangia.
Zygomycetes reproduce sexually by producing?
Zygospore.
Examples of zygomycetes are??
Mucor.
Rhizopus.
Absidia.
Ascomycetes reproduce asexually by?
Formation of conidia.
Ascomycetes reproduce sexually by?
Ascospores…. Present within a sac like structure called ascus.
Ascomycetes have septate hyphae.
T/F
True.
Examples of fungi in ascomycetes?
Aspergillus, Penicilum
Sexual reproduction of basidiomycetes is done by??
Basidiospores formed on basidia
Examples of fungi in basidiomycetes
Cryptococcus neoformans, mushrooms.
What are deturomycetes??
Group of fungi whose sexual phases are not identified.
Examples of deturomycetes are??
Coccocidiodis immitis, Paracoccocidiodis brasillensis
Candida albicans.
The types of vegetative spores are??
Chlamydospore.
Arthrospore.
Blastospore.
How are Blastospores formed?
They are formed from budding from parent cells.
How are Arthrospores formed?
Formed from segmentation and condensation.
What are chlamydospores??
Vegetative spores formed as thick walled resting spores.
What are conidiospores?
Spores borne externally kn the sides or tips of hyphae.
What are the types of ariel spores?
Conidiospores.
Sporangiospores.
Classify mycoses based on the route of acquisition?
Exogenous
Endogenous
What are the modes of transmission of an exogenous fungi?
Airborne.
Cutaneous.
Percutaneous.
Based on site, mycoses are classified as??
Superficial
Cutaneous
Subcutaneous
Systemic
Superficial mycoses are also called?
Tinea
Examples of superficial mycoses are?
Piedraia hortae.
Trichosporon cutaneum.
What disease does piedraia hortae cause?
Black piedraia, a disease of the hair shaft.
What Phylum does piedraia hortae belong to?
Ascomyocota.
Which fungi causes white piedraia??
Trichosporon cutaneum
Trichosporon cutaneum belongs to which Phylum??
Basidiomyocota.
The main fungae responsible for cutaneous mycoses are??
Microsporon.
Trychophyton.
Epidermophyton.
What factors can be considered the virulence factors of cutaneous fungi?
Ability to degrade keratin.
Ability to grow on skin as non invasive saprotrophs.
The two Subcutaneous mycoses include??
Human mycethoma
Sporotrichosis
Human mycethoma is caused by?
Madurella mycethomatis and M. Grisea.
The common name for human madurella is called??
Madura foot.
Sporotrichosis is caused by??
Sporotrix schenckii.
The telomorph stage of sporotrix is called?
Ophiostoma stenoceras.
The anamorph stage of sporotrix is called?
Sporothrix.
Sporotrichosis is also called?
Rose handler’s disease.
What is the pathogenesis of sporotrix schenckii??
- Enters through a minor wound and spreads to lymphatic system
- Forms conidia at 25°C and buds at 37°C.
- The yeast form is distributed by the lymphatic system and it causes disseminated infections resulting in infections of the lungs, bones, joint, endophthalmitis, meningitis, invasive Sinusitis.
What is systemic mycoses?
Diseases caused by fungi that affect the whole body.
System mycoses are divided into?
Diseases caused by primary pathogens.
Diseases caused by opportunistic pathogens.
The primary deep pathogens infect the host via??
The respiratory tract.
The opportunistic pathogens infect the host via?
Respiratory tract, alimentary canal, intravascular devices.
The primary systemic pathogens include?
Coccocidiodis immitis
Histoplasma capsulatum
Paracoccocidiodis brasillensis
Blastomyces dermatidis
The opportunistic pathogens include?
Cryptococcus neoformans
Candida
Aspergillus spp
Penicilum marneffi
Examples of superficial mycoses include
Pityrasis versicolor
Piedraia hortae
White piedraia
Tinea nigra
Types of tinea infection include?
Tinea capitis
Tinea unguium
Tinea pedis
Tinea corporis
Tinea cruris
Tinea capitis affects the
Scalp
Tinea cruris affects the
Groin
Tinea unguium affects the
Nail
Tinea corporis is??
ringworm
For laboratory diagnosis of fungi, where are specimens gotten from?
Csf
Blood
Tissue, bone marrow
Vaginal secretions
Stool
Urine
Saliva
What are the procedures adopted for direct examination of fungal specimen?
Wet mount
Histopathology
Flourecent antibody
Gram staining
The diagnosis of fungi is done by two ways which are?
Clinical diagnosis.
Laboratory diagnosis.
Clinical diagnosis gives presumptive diagnosis of fungal infections.
T/F
True.
In clinical diagnosis, how is superficial and Subcutaneous fungal infection detected?
They produce characteristic lesions that suggest their fungal etiology.
In clinical diagnosis, what signifies systemic fungal infection??
There’s no sign or symptom that signifies systemic fungal infection.
For KOH wet mounts, what systems are used?
Slide KOH.
Tube KOH.
Nigrosin and wet India ink.
How is slide KOH done?
- The specimens can be identified in wet mounts after partial digestion with 10% - 20% KOH.
- The clinical specimen like hair, nail, skin should be mounted under cover slip in KOH on slide.
- It clears btw five to twenty minutes depending on the thickness.
- A slight warming over a low flame hastens digestion of keratin.
What can be supplemented for KOH??
Dmso.
Flourecent dye.
Calcoflour white (Detects even scanty amount of fungi).
Why is tube KOH prepared??
It is prepared for biopsy specimens which take longer time for resolution.
How is tube KOH prepared??
A homogenised biopsy tissue is dissolved in 10% KOH and examined after incubating the sample overnight at 37°C.
Wet India ink and Nigrosin are used for making diagnosis for capsulated fungi.
T/F
True.
In histopathology, the h&e stain is used for?
It is a routine procedure and stains most of fungi.
List the specific fungal stains
Periodic acid schiff.
Grocott gomori’s methanamine silver.
Gridely stains.
Which stain is used to show capsular material of Cryptococcus, endospores etc?
Mayer’s mucicarmine stain.
What is the use of Flourecent antibody staining?
Used to detect fungi antigen in pus, blood, csf, tissue impression smears etc.
What limits the use of Flourecent antibody staining?
Restricted availability of specific antisera.
The media commonly employed for fungal culture is??
Emmon’s modification of sabouroud dextrose agar.
The pH of fungal culture is?
5.4
What is the function of gentamycin and chloramphenicol in fungal culture?
To prevent bacteria invasion.
What is the function of cycloheximide in fungal culture
To inhibit saprophytic fungi.
The serologic tests used in detection of antibodies include?
Immunodiffusion
Elisa
Complement fixation
Whole cell aggultination
The serologic tests used in detection of antigens are?
Latex particle aggultination
Elisa
What are the molecular techniques used in detection of fungi?
PCR
Dna probes
