Fungi And Drugs Flashcards
New class semisynthetic antifungal which inhibits b glucan synthesis in cell wall
Echinocandins—- anidulafungin
Caspofungin
Micafungin
Treatment for cryptococcal meningitis
Ampho b with flucytosine
Mechanism of action of flucytosine
Acts in nucleus
Gets converted by cytosine deaminase to 5 FU and inhibits DNA RNA synthesis
Doc for suppression of cryptococcal meningitis in AIDS patient
Fluconazole
Most important adverse reaction of azole esp ketoconazole
Cytochrome p450 inhibition
testosterone synthesis is inhibited causing gynaecomastia
Doc for dermatomytosis
Fungal infection of skin finger and toe nails and hair
Terbinafine
Antifungal that inhibits microtubule function
Greisofulvin
Adv reaction of griesofulvin
Teratogenic
Carcinogenic
Disulfiram like reaction
Increase cytochrome p 450 and warfarin metabolism
greisofulvin doesnt act on which fungi
Candida and other deep mycosis
What makes griesofulvin usable in dermatophytosis
Gets concentrated in keratinocytes skin hair nails
Concentrated in cells infected with tinea
Greisofulvin is fungistatic or cidal
Greisofulvvin is fungistatic
Prevents new keratinocytes from getting infected
Old cells still harbour infection till shed off
Ulcer or granuloma with macrophages showing intracellular yeast
Histoplasma capsulatum
Histo hides in macrophages
And are smaller than rbcs
Granulomatous nodules in lung skin bone
Biopsy shows broad based budding
Blastomycosis
Skin lesions can be verrucous and mimic scc
Budding yeast with captain wheel type formation
Paracoccidiodo mycosis
Seen in latin america
Skin or bone disease
Biopsy shows large spherule which is larger than rbc and contains numerous endospores
Coccidiodo mycosis
Seen in deserts of usa california
Desert rheumatism
Desert bumps—- erythema nodosum
Coccidiodo mycosis
Spherule with endospores
Inhalation of dust in earth quake and archeological excavation
Inhalation of spore laden dust
Coccidiodomycosis
Deserts california
Spherule which is much larger than rbc containing numerous endospores
Name the cutaneous mycosis
Dermatophytosis is tinea capitis, corporis, cruris, pedis and unguium
Tenia versicolor also called pityriasis versicolor
Cutaneous mycosis skin scrapings on koh mount would show
Filamentous septate hyphae
Not budding yeast
Ring worm with central clearing and acquired from pets or farm animals
Tinea corporis
Causative organism for pityriasis versicolor
Malessezia spp - pityrosporum species
It is a yeast like fungus
Why hypopigmentation occurs in pityriasis versicolor
Malessezia spp infection
Lipid breakdown produces acid
Acid inhibits tyrosinase
Melanin synthesis inhibited
Microscopic appearence of pityriasis versicolor
Spagetti and meatball appearence
Caused by malessezia
Treatment of pityriasis versicolor
Selenium sulfide
Other topical or old antifungals