Mycoses

Fungous allergies

allergies may result from sensitization to specific fungal antigens

Mycotoxicoses

fungi may elaborate or indirectly generate substances that have a toxic effect

Mycoses

Infection produced by fungi which may be classified according to the areas of body affected by fungi

Superficial mycoses

Cosmetic fungal infections of the skin or shaft

Malassezia furfur

Causative agent of tinea/pityriasis versicolor

Tinea/pityriasis versicolor

Chronic recurrent condition involving stratum corneum of skin

Tinea/pityriasis versicolor

Characterized by scaly patches of hypo to hyper pigmentation of skin of moist humid areas

Seborrheic dermatitis

dandruff in adults and Cradle cup in babies

Malassezia furfur

Cluster budding yeast or Spaghetti and meatballs appearance in 10% KOH preparation

Malassezia furfur

fried egg colonies in SDA culture with olive oil overlay

golden yellow fluorescence

appearance of tinea versicolor in Wood's lamp

Positive

Test for urease in M. furfur

Topical lotions: Selenium sulfide shampoo, ketoconazole shampoo or cream, and terbinafine cream

Treatment for Tinea versicolor

Hortaea werneckii

Most common causative agent of tinea nigra

Exophiala werneckii and Phaeoannellomyces werneckii

Other causative agents of tinea nigra

Tinea nigra

Characterized by painless, black, non-scaly patches present on palm and sole (thick skin) more commonly in females

Hortaea werneckii

Black colored yeast-like fungus

Topical ketoconazole cream

Treatment for Tinea nigra

Hortaea werneckii

Branched, septate hyphae with 2 celled oval yeast cells with melanized cell walls

Hortaea werneckii

Black, yeasty colonies that develop short olive gray mycelia with age

Piedra

Infection of hair shaft that produces hair breakage due to poor personal hygiene

White piedra

Fungal infection of facial, axillary, or genital hairs and less common in scalp

White piedra

Soft, white, yellowish, beige, or greenish nodules on hair shaft and less firmly attached

10% KOH or 25% NaOH with glycerol

Microscopic examination for white piedra

Trichosporon beigelii

Causative agent of white piedra

White piedra/Trichosporon beigelii

Intertwined hyaline septate hyphae breaking up into oval or rectangular arthroconidia

White piedra/Trichosporon beigelii

Raised, waxy appearance colonies and radial furrow and irregular folds on SDA or PDA

Positive

Test for urease in T. beigelii

White piedra/Trichosporon beigelii

Showed septate hyphae, arthroconidia, and budding blastoconidia on Lactophenol cotton blue (LPCB) mounts

Black piedra

Fungal infection of hair scalps less common in beard and pubic areas

Black piedra

Hard, dark brown to black gritty nodules firmly attached on hair shaft

Piedraia hortae

Causative agent of black piedra

Black piedra/Piedraia hortae

Compact masses of dark, septate hyphae with round to oval asci containing 2-8 on 10% KOH

Cutaneous mycoses/dermatomyces

Causes Tinea/Ringworm Infections that extend deeper into epidermis

Cutaneous mycoses/dermatomyces

Restricted to keratinized layers of skin, hair, and nails

Dermatophytes

Causative agents of cutaneous mycoses

Microsporum spp.

Infect skin and hair

Epidermophyton spp.

Infect skin and nail

Trichophyton spp.

Infect skin, hair, and nail

Microsporum: Macroconidia

Rough/thin to thick walled and spindle shaped that contains 4-15 cells and numerous in number

Microsporum: Microconidia

Club shaped, single and few in number

Epidermophyton: Macroconidia

Smooth/thin walled and club shaped that contains 2-5 cells and Numerous in number

Trichophyton: Macroconidia

Smooth/thin walled and pencil shaped that contains 3-7 cells and few in number

Trichophyton: Microconidia

Round to club shaped in grapelike clusters and few to numerous in number

Tinea capitis

Ringworm of scalp

Tinea capitis

Circular bald patches with short hair stubs or broken hair within hair follicles

Trichophyton verrucosum

Causative agent of kerion of tinea capitis

Favus

most severe type of tinea capitis

Trichophyton schoenleinii

Causative agent of favus of tinea capitis

Ectothrix

fungus on surface of hair

Microsporum audouinii, Microsporum canis, and Trichophyton mentagrophytes

Causative agents of Ectothrix of tinea capitis

Endothrix

fungus inside hair shaft

Trichophyton tonsurans and Trichophyton violaceum

Causative agents of endothrix of tinea capitis

Tinea barbae

Ringworm of beard hair

Tinea barbae

Edematous and erythematous lesion

Trichophyton rubrum and Trichophyton mentagrophytes

Causative agents of Tinea barbae

Tinea manuum

Ringworm of hands

Tinea manuum

Dry scaling eruption of one palm

Trichophyton rubrum

Causative agent of Tinea manuum

Tinea unguium

Ringworm of nails Also known as onychomycosis

Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum

Causative agents of tinea unguium

Tinea corporis

Ringworm of body

Tinea corporis

Pruritic Clinical patches with advancing red, vesiculated border and central scaling

Microsporum canis and Trichophyton mentagrophytes

Causative agents of tinea corporis

Tinea cruris

Ringworm of groin Also known as Jock Itch

Tinea cruris

Pruritic Erythematous scaling lesion in intertriginous areas

Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum

Causative agents of tinea cruris

Tinea pedis

Ringworm of interdigital spaces of foot Also known as Athlete’s Foot

Acute tinea pedis

itching and red vesicular

Chronic tinea pedis

itching, scaling, and fissures

Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum

Causative agents of tinea pedis

Microsporum audouinii

Pectinate (comb-like) septate hyphae with terminal chlamydoconidia with pointed ends

Microsporum audouinii: Tinea capitis

Intercalary chlamydoconidium

Microsporum canis

Numerous thick-walled, spindle-shaped macroconidia with tapered ends and contains 6-15 cells; Zoophilic

Microsporum canis: Tinea capitis, corporis, and barbae

Pyriform shaped conidia

Microsporum gypseum

Produces numerous thin-walled, elliptical macroconidia and contains 4-6 cells and geophilic

Microsporum gypseum: Tinea capitis, corporis, favosa

Ellipsoidal 4-6 cells in macroconidia

Epidermophyton floccosum

Macroconidia present only

Trichophyton mentagrophytes

Hair Perforation Test (+) and Urease (+)

Trichophyton mentagrophytes

Round clustering microconidia and Cigar shaped macroconidia

Trichophyton mentagrophytes: All types of Tinea

Spiral hyphae “en grappe”

Trychophyton rubrum

Forms deep red reverse on PDA and Tear-drop shaped microconidia

Trychophyton rubrum

HPT (-) and Urease (-)

Trychophyton rubrum: All types of Tinea

“en thyrse”

Trychophyton verrucosum

Produces only chlamydoconidia on SDA or PDA and Elongated rat tail macroconidia on thiamine-enriched media

Trychophyton verrucosum: Tinea corporis and barbae

Ringworm in cattle

Trychophyton verrucosum

Culture requires inositol

Trichophyton tonsurans

Thiamine dependent

Trichophyton tonsurans: Tinea capitis and corporis

Originates from aborigines

Trichophyton schoenleinii: Tinea capitis, favosa, and corporisfavus

Scutula or Permanent hair loss

Trichophyton schoenleinii

Causes favus type of tinea capitis

Favus of Tinea Capitis

pale green in Wood's lamp

Ectothrix of Tinea Capitis

bright green in Wood's lamp

Hair perforation test

put infected hair and small amount of water and a drop of yeast extract solution; Incubate at 30C for 7 days

Trichophyton rubrum

Negative for hair perforation test

Trichophyton mentagrophytes

positive for hair perforation test

Subcutaneous mycoses

infections initially involve the deeper layers of dermis, subcutaneous tissue, or bone. Most infections have a chronic or insidious growth pattern and characterized by granuloma

Sporotrichosis

Chronic subcutaneous pyogranulomatous disease

Rose Gardener’s Disease

Other name of sporotrichosis

Sporothrix schenckii

Thermally dimorphic fungi that can cause sporotrichosis