1. The morphology and biology of the

fungi

Classification of medically

important fungi

• Fungal morphology and structure

• Antifungal (AF) - Mechanisms of action

• Fungi - biology and physiology

• Fungal infections (FI) - classification

The goal of teaching: 2. Common fungi which primarily cause skin,

hair and nail FI

• Malassezia - morphology, biology

Pathogenesis of pitiriasis versicolor,

Pathogenesis of seborrheic dermatitis

• Trichophyton - morphology, biology

• Microsporum - morphology, biology

• Epidermophyton - morphology, biology

Pathogenesis of dermatomycoses

3. Common fungi which causes

superficial / invasive / oprtunistic FI

• Candida - morphology, biology

Pathogenesis

• Cryptococcus - morphology, biology.

Pathogenesis

• Aspergillus - morphology, biology.

Pathogenesis

• Fusarium - morphology, biology.

Pathogenesis

4. Other fungi which causes of superficial /

invasive oprtunistic FI

• Penicillium - morphology, biology

Pathogenesis

• Zygomycetes (Mucor, Rhisopus, Absidia) -

morphology, biology.

Pathogenesis

• Pneumocystis - morphology, biology.

Pathogenesis

COMMON CAUSES OF FI Skin, hair, nail:

Malassezia

Trichophyton

Microsporum

Epidermophyton

Candida

Superficial mycoses: :

Malassezia

Exophiala (Cladosporum) werneckii

Trichosporon beigelli

Piedraea hortae

...

Cutaneous mycoses

dermatomycoses / tinea: Trichophyton

Microsporum

Epidermophyton

Candida

Aspergillus

…

Mucocutaneous mycoses:

Candida

Geotrichum

Rhinosporidium seeberi

...

Othomycoses:

Aspergillus

Candida

...

Keratomycoses:

Fusarium

Aspergillus

Onichomycoses:

Candida

Dermatophytes

Undermatophytes moluds

Malassezia (Pityrosporum)

• Yeasts, NF of skin, lipophilic species:

M.furfur, M.sympodialis, M.globosa...

• Unlipophilic species:

M. pahidermatis

Pathogenesis: • Pityriasis versicolor

(tinea versicolor)

• Malassezia foliculitis

• Seborrheic dermatitis (pityriasis

simplex capitis - dandruff)

• Atopic dermatitis

(systemic infection - rare / lipid th)

LDg/ DMP

Culture

Th/ AF local

MM2

Pytiriasis versicolor (tinea versicolor)

• Slight, recurrent disease of the

superficial layers of the skin (stratum corneum)

• Lesions- with small circular

flakes (scaling)

• Predisposing factors:

sweating, gender, genetic basis ...

• Predilection sites:

chest, back, shoulders

• System types: infants and adults, CVC

DDG: erithrasma, vitiligo

Hypo-pigmentation Hyper-pigmentation

Dermatophytes

Trichophyton (around 20 species)

Microsporum (around 17 species)

Epidermophyton (2 species)

• Highly contagious, cosmopolitan distribution

• Keratinophilic: hair, nails, and superficial layer of skin

(reproduction)

Anthropophilic species

Zoophilic species

Geophilic species

Dermatophytes

Zoophilic species:

Microsporum

M. canis

M. equinum

M. gallinae

Trichophyton

T. equinum

T. mentagrophytes

T. simii

T. verrucosum

The most frequent species in human: • Trichophyton rubrum

• Trichophyton interdigitale

• Epidermophyton floccosum

• Microsporum canis

• Trichophyton verrucosum

Geophilic species:

Microcporum

M. gypseum

M.nanum

M.persicolor

Trichophyton

T. ajeloii

Antropophilic species:

Microsporum

M. audouinii

M. ferrugineum

Trichophyton

T. concentricum

T. interdigitale

T. rubrum

T. schoenleinii

T. tonsurans

T. violaceum

Epidermophyton

E. floccosum

Source of infection: people, animals, soil

Dermatophytes

Trichophyton

Microsporum

Epidermophyton

Macroconidia

(rare)

Microconidia

(numerous)

Macroconidia

(numerous)

Microconidia

(rare)

Macroconidia

(only)

Microconidia

(absent)

• Macroconidia / multicellular

fusiform

cylindrical

drumstick shape

• Microconidia / unicellular

pyriform

in clusters

Microscopic characteristics of

dermatophytoses

D E R M A T O F I T I

Localization of dermatophytes and

characteristics essential for identification

Trichophyton I group

(skin, nails, hair - type ectotrix)

» T. mentagrophytes

» T. rubrum

» T. verrucosum

Trichophyton II group

(skin, nails, hair - type endotrix)

» T. tonsurans

» T. schoenleinii

» T. violaceum

macroconidia rare (pencil shaped 3-8 cells ) numerous microconidia in clusters

Microsporum

(hair and skin)

Numerous macroconidia

(elliptical, fusiform 3-7 cells)

Macrodonidia by hyphae, one

Epidermophyton

(skin and nails)

Only macroconidia

(rounded, with 2-4 cells)

DERMATOPHYTOSES TINEA/RINGWORM/DERMATOMYCOSES

Indicate infection of the superficial layers of skin, hair and nails

caused by dermatophytes or other fungi

DERMATOPHYTOSIS (Tinea)

localization

Trichophyton

(around 20 species)

Skin

Hair

Nails

Herpes tonsurans

LDg/ DMP

Culture

Th/ AF MM2

Herpes tonsurans

LDg/ DMP

Culture

Th/ AF

MM2

Herpes tonsurans Trichophytia superficialis

Trichophyton mentagrophytes

LDg/ DMP

Culture

Th/ AF MM2

Kerion Celsii Sycosis barbae

Trichophytia profunda

LDg/ DMP

Culture

Th/ AF MM2

Kerion Celsi

LDg/ DMP

Culture

Th/ AF MM2

Sycosis barbae

LDg/ DMP

Culture

Th/ AF MM2

Favus -Trichophyton schoenleinii

LDg/ DMP

Culture

Th/ AF MM2

Tinea imbricata - T. concentricum

Trichophyton mentagrophytes v. interdigitale

Onychomycosis - T. mentagrophytes

Itraconazole pulse

Dr Decroix , Belgium

Microsporum

(17 species)

Skin

Hair – type ectotrix

rare - nails

Microsporum gypseum

Microsporum canis

Microsporum gypseum Microsporum canis

Microsporia

LDg/ DMP

Culture

Th/ AF

Epidermophyton

(2 species)

Skin

Nails

Epidermophyton floccosum

LDg/ DMP

Culture

Th/ AF

Tinea corporis

Tinea pedis

Epidermophyton floccosum

Macroconida (phase contrast 400X) Macroconidia (LFCB 400X)

Dermatophytid – immunopatological manifestation

Fungal Ag in complex with Ab in the skin

Sima Milošević (1896-1943)

Epidermophyton floccosum (Harz) Langeron et Milochevitch

Trichophyton schoenleinii (Lebert) Langeron et Milochevitch

Langeron, 1950.

Trichophyton milochevitch