Mycology and Fungus Flashcards
Define dimorphic fungi
Fungi which can exist both as mould and yeast (Yeast in tissue, mould in vitro)
e.g. Coccidioides Immiti
What is yeast and how does it reproduce?
Single celled organism
Asexual reproduction
What is mould and how does it reproduce?
Multi-cellular organism
Spore formation
What are 3 common fungal infections?
1) Tinea Pedis
2) Nappy Rash
3) Onychomycosis (Terbinafine to treat –> Reaches poorly perfused sites)
What is the main way that antifungal treatments treat the human body? What sites do they target?
Selective toxicity
1) Ergosterol: Plasma in cell membrane
2) Fungal cell Walls: Chitin and Polysaccharides
How do the 2 main types of antifungal treatment work?
1) Amphotericin: Targets plasma membrane and ergosterol –> Pore formation –> Cell death
2) Azoles: Affect synthesis of ergosterol
What are 4 disadvantages of azoles?
1) High first pass metabolism –> Low bioavailability
2) ADR: Hepatitis
3) CYP450 leads to drug interactions and poor drug metabolism
4) Resistance develop
Describe candida
Yeast that grows in warm, moist areas with high levels of β-D-Glucan
Which test identifies resistant fungal antigens?
β-D-Glucan
What are 4 properties of mycobacteria?
1) Aerobic
2) Non-motile
3) Non-spore formation
4) Bacilli
What are moulds composed of and what is a main example?
Composition: Hyphae: Branched filamentous filaments
Aspergillus fumigatus
Which fungal infection is an example of HIV and why?
Pneumocystis pneumonia: Opportunistic infection so will only be found in non-healthy immunocompromised individuals
