U1 LEC: INTRO TO MYCOLOGY (PT 2) Flashcards
Determinants of Pathogenecity
- Thermotolerance
- Adaptation to a parasitic lifestyle
- Adhesins
- Use of enzymes to attach host tissues
- Dimorphism
- Evasion of immune response
- Presence of cell wall molecules that are barriers that resist lysis by phagocytes and antifungal agents
- Toxin Production
T/F: There are fungal elements that can produce toxin.
True
Toxin that is produced by fungi
Aflatoxin
Refers to causes of mycotic/fungal infections
Mycoses
Practical Classification of Fungi
- Superficial/Cutaneous
- Subcutaneous
- Systemic
- Opportunistic
Fungal Toxicology
Mycotoxicoses
Mode of Transmission
Ingestion of mycotoxins
Toxins are coming from?
Amanita mushroom
Examples of Amanita mushroom
- Amanita muscaria
- Amanita phalloides
causes Psychoactive effects and Hepatotoxins
Amainitin, Phalloidin
This causes Ergotism or St. Anthony’s Fire
Ergot Alkaloids
Ergot Alkaloids cause?
Ergotism or St. Anthony’s Fire
Ergot Alkaloids are derived from?
Claviceps purpurea
Alkaloids include?
Ergotamine and Lysergic Acid Diethylamide (LSD)
Effect of Alkaloids
Vascular and Neurologic effects
Alkaloids cause to develop?
Gangrene, Convulsions
Aflatoxins (coumarin derivatives) are produced by?
Aspergillus flavus
This is found if staple commodities are improperly stored, enter the food chain infecting livestock, and infection happens when spoiled grains and peanuts are ingested.
Aflatoxin
Aflatoxin B1 can lead to?
Hepatic Carcinoma and Liver Damage
This refers to the exaggerated immune response.
Hypersensitivity Reaction
This is manifested by asthmatic reaction.
Allergies
Asthmatic reactions are mediated by?
IgE
Skin test reactions under Allergies
Eosinophilia, “wheal and flare” (redness, swelling)
This is due to immediate hypersensitivity response to spores.
Allergies
Hypersensitivity reaction is caused by?
spore inhalation
Designed to give information in aiding the clinician in selecting the antifungal agent to treat a specific antifungal disease
Anti-fungal therapy
Polyene Macrolide Antifungals
Anti-fungal agents
- Amphotericin B
- Nystatin
Polyene Macrolide Antifungals
Source of Ampothericin B
Streptomyces nodosus
Polyene Macrolide Antifungals
MOA
Binds ergosterol to alter selective permeability
Polyene Macrolide Antifungals
Usage (Amphotericin B)
For deep seated fungal infections
- Candida
- Cryptococcus
- Mucorales
Polyene Macrolide Antifungals
Precaution
toxic to the kidney
Polyene Macrolide Antifungals
Source of Nystatin
Streptomyces noursei
Polyene Macrolide Antifungals
Usage (Nystatin)
Oral or vulvovaginal candidiasis
Grisans
Antifungal agent
Griseofulvin
Grisans
Source
Penicillum species
Grisans
MOA
Inhibits microtubular function
Grisans
Usage
Oral agent for Dermatophytosis (not responsive azoles)
Nucleoside Analogs
Antifungal agent
5-Fluoro-cytosine (Flucyotsine)
Nucleoside Analogs
MOA
Inhibits DNA and RNA synthesis
Nucleoside Analogs
Usage
Candida and Cryptococcus infections (synergistic with Amphotericin B)
Azole Derivatives
Antifungal agents
- Clotrimazole
- Miconazole
- Fluconazole
- Ketoconazole
- Itraconazole
Azole Derivatives
MOA of Clotrimazole and Miconazole
Disrupt cell membrane by interfering with synthesis of Ergosterol
Azole Derivatives
MOA of Fluconazole
Inhibit cytochrome p-450 dependent enzymes
Azole Derivatives
Usage of Clotrimazole and Miconazole
Dermatophytosis (Mild)
Azole Derivatives
Usage of Fluconazole
Candida or Cryptococcus infections (Oral or IV)
Azole Derivatives
Usage of Ketoconazole
Mild Paracoccidiodomycosis (Oral or topical)
Azole Derivatives
Usage of Itraconaxole
- Aspergillosis
- Sporotrichosis
- Cryptococcosis
- Onychomycosis
Echinocandins
Antifungal agents
- Caspofungin
- Anidulafungin
Echinocandins
MOA
- semisynthetic lipopeptides that target fungal cell wall
- inhibit glucan synthesis by targeting on 1,3-beta-D-glucan synthase
Echinocandins
Usage
Candida infections
Allylamines
Antifungal agents
- Terbinafine
- Naftifine
- Selenium sulfide
- Potassium Iodide
Allylamines
MOA
interfere cell wall synthesis
Allylamines
Usage of Terbinafine and Naftifine
skin, nail fungal infections (topical)
Allylamines
Usage of Selenium sulfide
Tinea versicolor
Allylamines
Usage of Potassium Iodide
Cutaneuous/lymphatic sporotrichosis
Clinically used antifungals
Targeting cell wall/membrane
- Ergosterol Inhibitors
- B-glucan synthase inhibitors
Clinically used antifungals
Ergosterol inhibitors
- Lanosterol 14a-demethylase inhibitors
- Ergosterol binding
- Squalene monooxygenase inhibitors
Clinically used antifungals
Lanosterol 14a-demethylase inhibitors
Azole (Imidazole, Triazole)
Clinically used antifungals
Ergosterol binding
Polyenes (Amphotericin B, Nystatin, Pimaricin)
Clinically used antifungals
Squalene monooxygenase inhibitors
Allylamines, Benzylamines, Thiocarbamate
Clinically used antifungals
B-glucan synthase inhibitors
- Echinocandins
- Ibrexafungerp
Clinically used antifungals
Intracellular targets
- Pyrimidine analogues/thymidylate synthase inhibitors
- Mitotic inhibitors
- Aminoaxyl tRNA synthetase inhibitors
Clinically used antifungals
Pyrimidine analogues/thymidylate
Flucytosine
Clinically used antifungals
Mitotic inhibitors
Griseofulvin
Clinically used antifungals
Aminoaxyl tRNA synthetase inhibitors
Tavaborole
Treatments for Mold Allergy
- Decongestants
- Antihistamine drugs
- Immunotherapy
- Home-proofing (filter)