Medical Mycology

Front 1

Components and description of fungi

Back 1

- Eukaryotic : true nucleus
- Cell walls : composed mainly of chitin
- Reproduce by spore formation
- Can be unicellular (yeast) or multicellular (hyphae)
- Heterotrophic : Absorb nutrients without having the capacity of synthesizing them, export many toxins.

Front 2

Types of fungi and definitions

Back 2

- Hyphae : Tubular structure
- Mycelium : Group of hyphae
- Yeast : Unicellular round fungal cells
- Conidia : Asexual spores
- Conidiophore : Proiuces conidia

Front 3

Antifungal therapy targets

Back 3

- Cell membrane
- DNA synthesis
- Cell wall

Front 4

Cell membrane antifungals

Back 4

- Azoles : Fluconazole is common use
- Allylamines : Terbinafine for topical superficial fungal infections
- Polyenes : highly toxic (topical use only)

Front 5

DNA syntesis inhibitor antifungal

Back 5

- 5-Flucytosine : Only useful in combination therapy

Front 6

Cell wall active agent

Back 6

- Echinocandins : Breaks the wall by inhibiting cell wall B-glucan

Front 7

Pilobolus

Back 7

- Grows in cow feces
- Uses an hydrostatic cannon guided by light to shoot the spores

Front 8

Apergillus allergic disease

Back 8

- Farmer's lungs
- Extrinsic alveolitis

Front 9

Asthma

Back 9

- Aspergillus is a common cause of asthma

Front 10

Classification of fungal infections

Back 10

Superficial : yeast and molds
Invasive : Yeast (sytemic, pulmonary or subclinical disease), Dimorphic (primary pulmonary with dissemination) and molds (primary pulmonary)

Front 11

Superficial candidiasis (candida albicans)

Back 11

- Yeast
- Can cause OPC (thrush) which is a surperficial infection of the oral mucosa
- Can cause esophageal candidiasis which is often a complication of OPC
- Can cause vaginitis which is common after antibiotic therapy
- Can cause skin and nail infections

Front 12

Invasive candidiasis (candida albicans)

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- Candida infection of the bloodstream
- Gain entry from breaches in the mucosal surface
- Mortality of nearly 50%
- Diagnosed by blood culture or Beta-D-glucan
- Treated with echinocandin then step down to azoles when patient is stable

Front 13

Cryptococcus neofarmans

Back 13

- Encapsulated yeast
- Associated with bird feces
- Inhalation of yeast cells or spores
- Initially an asymptomatic pulmonary infection with dissemination
- Presents as chronic meningitis
- Very associated with HIV
- Can be diagnosed by culture and antigen testing
- Tretaed with amphotericin B the switch to fluconazole
- Lifelong suppresive therapy needed

Front 14

Histoplasmosis

Back 14

- Dimorphic
- Present in the soil and in bats
- Infections made by the airborne spores
- Pulmonary infection similar to tuberculosis
- Enters latent phase
- Diagnosed by antigen testing of urine, blood culture and respiratory secretions culture
- Severe form is treated with Amphotericin B and step down to azole after
- Local disease treated with an azole

Front 15

Tinea pedis or corporis

Back 15

- Mold
- Also called athlete's foot
- Treated with topical antifungals (azoles or terbinafine)
- Usually caused by Tinea rubrum
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Front 16

Tinea unguium (Onychomycosis)

Back 16

- Mold
- Invasion of the nail plate
- Common cause is Tinea rubrum
- treated with systemic azoles or terbinafine

Front 17

Aspergillus fumigatus

Back 17

- Invasive mold
- Affects mostly bone marrow transplant patients and other immunosupressed patients
- Deadly
- Diagnosed by culture or by galactomannan assay
- Rapidity of treatment is key
- Treated with voriconazole or liposomal AmB