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mycology Introduction. Essential growth factors. Classification of fungi. Clinical syndromes. Colonization and resultant disease. Superficial Mycoses. Cutaneous Mycoses. Systemic Mycoses. ٢

Introduction Fungi are characterized with Heterotrophic, Eukaryotic, non Chlorophyll. Are not obligate animal parasites but Dermatophites. Fewer than 100 species are associated with human diseases. ٣

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Essential growth factors Carbon source for energy metabolism and structure. Nitrogen source for metabolic reactions and structure. Purine and pyrimidine for synthesis of Nucleic acids and chitin. ٥

Circumstances for growth Optimum thermal growth in 22-2727 C.. Optimum PH for growth in 5.6-7.. Optimum Humidity for growth in 75-85%. ٦

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Classification Phylum,Chitiridiomycota. Chitiridiomycota.(Oomycete) O t ) Phylum, Dikariomycota: Sub phylum, Zygomycota.(Rhyzopus,mucor) Sub phylum, Ascomycta.(Dermatophytes, y y Histoplasma) SubPhylum,Basidiomycota.(Cryptococcus) Subphylum,Deutromycota Deutromycota.(Candida, Malassezia) ٨

Clinical Syndromes Mycotoxicosis & Mycetismus.. Hypersensitivity Diseases.. Colonization of the host and infection. ٩

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Colonization and Infection Superficial Mycoses Cutaneus Mycoses Subcutaneus Mycoses Systemic Mycosis Opportunistic Mycoses ١١

Diagnostic methods Wood s light: (fluorescent lesions under UV in λ=395 n.m) Direct examination: KOH method, squeezed preparation, scotch tape method, stained preparation. Culture: On variable media, teased mount, slide culture method. Serology: ID, CIE, CF, LAT Molecular: PCR ١٢

Basic culture media S: sabouraud dextrose agar SC: S+Chloramphenicole SCC: SC+cyclohexamide CMA: Corn Meal Agar PDA: Potato Dextrose Agar PFA: Potato Flake Agar Czapek Dox Agar ١٣

Superficial Mycoses Pityriasis versicolor Pityrosporosis Tinea nigra Erythrasma Piedra Otomycosis ١٤

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Pityriasis i i versicolor ١٦

Definition A chronic, recurrent, macular, superficial fungal infection.. Caused by: Malassezia fur fur,m globosa,m restricta,m t sympodialis,m sloofeae,m pachydermatis,m obtusa M dermatis,m nana,m equi the lipophilic yeast, encountered in skin. ١٧

Clinical manifestation Macular, sharply marginated, very slightly raised. Sites of infection : Neck, flexor, aspects of arms, abdomen, axillae and pubic area. Papular form on seborrheic area of trunk. World wide. common in hot and humid climates. Treatment: White field, selenium sulfide Clotrimazol, Miconazol ١٨

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Mycological Diagnosis Macroscopically observation goldish-yellow fluorescence in front of Woods light. Direct smear:koh 10-20 20% or scotch tape. Microscopically result:spaghetti and meatball or blastoconidia and pseudohypha. Culture: Is not necessary in ordinary clinical situation. S+streptomycin+sterile olive oil. ٣٣

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Treatment Sulfur 3% Salicylic acid 2% Clotrimazole Ketoconazole ٤٤

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Dandruff ٤٦

Pityrosporosis Definition: Seborrheic dermatitidis or Pityriasis simplex, A chronic superficial infection with scales (dandruff). Cause: Malassezia globosa, Malassezia resticta. Clinical manifestation: Seborrhea sicca, Oleasa and Eczema, scales appears on scalp and face. Treatment: e t Selenium e sulfide, Perithion zinc ٤٧

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Mycological Diagnosis Direct examination: Skin scrapping from seborrheric lesions. Squeezing in a drop of water staining with methylene blue show large numbers of budding cells. Culture: is not necessary to make the diagnosis. ٥٣

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Malassezia yeasts Basidiomycetous yeasts Monopolar budiding Lipid dependent or lipophilic Currently 10 species (+ _ 2 ) ٦٠

The species M.furfur M.globosa M.sympodialis M.pachydermatis M.obtusa M.restricta M.slooffiae M.dermatis M.nana M.equi ٦١

Skin diseases Pityriasis versicolor: M.globosa, M. sympodialis, M.slooffiae, M. restricta, M.furfur (rare) Seborrheic dermatitis: M.restricta, M. globosa, M.sympodialis, M. furfur (rare) Atopic dermatitis: M.furfur, M. globosa andm. Restricta (90 90%), M. furfur and sympodialis, M.dermatis Mallassezia folliculitis: :? Dandruf:M. restricta and M.globosa Psoriasis: M. globosa, M. slooffiae, M. restricta Onychomycosis : M. furfur Mucosal sites :M. Furfur ٦٢

Other clinical importance of Malassizia yeast M. furfur : systemic and mucosal sites, bone marrow transplant patients (rare)neonate, nosocomial out breaks M. Pachydermatis : neonates, nosocomial outbreaks ٦٣

Associations of Malassezia on skin M. globosa, M. sympodialis, M sloofiae ھمچنين پوست سالم PVو در اغلب M.globosa + M. sympodialis 30% PV M. globosa + M. sloofiae 7% PV ٦٤

Animal relationships Cat: M. pachydermatis, M. sympodialsis M. fur fur Dog: M. pachydermatis, M. nana M. fur fur M. obtuse Horse: M. fur fur. M sloofiae, Mobtusa, M. globosa M. restricta. M. equi Cattle: M. globosa, M. furfur. M. sloofiae, M. sympoolialis, M. nana Sheep: M. sympodialis, M globosa, M. restricta t Ostrich: M. furfur ٦٥

Significance of the currently recognized species Sampling is difficult Purifying a culture is difficult ٦٦

Healthy skin M. sympodialis : Trunk (60%), glans penis M. glogosa : scalp, forehead, trunk (10%) glopesis M.slooffiae : trunk (1%) M. restrica : scalp(20 20%) M. furfur :low very low (but 11% Japan) M. pachydermatis : glans penis (4.1%) Neonaties: colonization with M. Sympodialis and globosa ٦٧

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Treatment Selenium sulfide Ketoconazole ٦٩

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Tinea nigra Definition: Disease of warm humid climates characterized by,macules on glabrous skin. Cause: Exophila werneckii (Cladosporium werneckii A yeast-like dematiaceus fungus, Saprobe, living i soil or vegetations. ti ٧١

Clinical manifestation Brownish or black macules On glabrous skin: palm, sole, body Sharply marginated, Asymptomatic Little or no scales on lesions Resemble to cutaneus silver nitrate stains. ٧٢

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Mycology Direct examination of skin scrapping by KOH 10-20 %. Result: Dark, septate t hyphae h and budding cells, swelling spores. Culture: On sabouraud medium: Yeast like cells often doublet form Dark,septate hyphae, clusters of conidia. Treatment: salicilate 2%, sulfure 3%. ٧٤

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Erythrasma ٧٧

Erythrasma Definition: Macular, lesions on wrinkle area skin. Cause: Corynebacterium minutissimum i from diphtheroid bacteria. Clinical manifestation: Red to Brownish red and black macules on wrinkle area skin : groin, axilla and breast. ٧٨

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Mycological Diagnosis Direct Examination: Scrapping of macular lesions squeezing in a drop of water. Staining with gram or methylene blue show: Diphtheroid, China characters and filamentous bacilli, gram positive. Culture is not necessary. ٨٤

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Treatment Erythromycine ٩٣

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Black piedra Definition: A hair disease of western hemisphere tropics and Indonesia. Cause: Piedraia i hortea; a saprobe inhabiting the soil in tropics. ٩٥

Clinical manifestation Black nodules along the hair shaft Multiple, hard, firmly adherent Size; up to 1mm in diameter On hairs of the scalp, beard, moustache. ٩٦

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Mycology Direct examination: Mature nodules containing asci Pigmented hyphea. On sabouraud Agar after 21 days: Dark, thick walled and septate t hyphae h Swollen cells and chlamydospore Sometimes production of asci ٩٨

White Piedra A hair disease seen occasionally in south America.. Cause: Trichosporon beigelli ٩٩

Clinical Manifestation Whitish or brownish nodules along hairshaft. Size: up to 1mm in diameter Hair are weak and fractured The favored sites; axilla,,p pubic hair, beard, moustache and scalp. ١٠٠

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Mycology Direct examination: Blastoconidia and arthrospores within the hair shaft and on the surface. Culture on Sabouraud medium, C.M.A : Hyphae and pseudohyphae h Blastoconidia (single or short chains) Ath Arthrospores (rectangular). ١٠٢

Treatment HgCl2 ١٠٣

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M.Fur fur ١٠٥

M.globosa ١٠٦

M.pachydermatis ١٠٧

M.sympodialis ١٠٨

M.slooffiae ١٠٩

M.obtusa ١١٠

M.restricta ١١١

M.dermatis ١١٢