Tinea nigra. Dr. Ensieh Zibafar

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2 Piedra & Tinea nigra Dr. Ensieh Zibafar

3 SUPERFICIAL MYCOSES -Tinea versicolor -Tinea nigra -Piedra -Otomycosis -Erythrasma * -Trichomycosis Axillaris *

4 Piedra Means Stone in Spanish White Piedra Black Piedra

5 WHITE PIEDRA Definition: -An uncommon, asymptomatic fungal infection of pubic, facial, axilla or scalp hair with grayish-white soft nodules outside of the hair shafts. -Synonyms: Molestia de Bi Beigel, ltih Trichomycosisnodularisi i (nodusa), Tinea nodosa, Beigel disease

6 HISTORY: -In 1865, Beigel first described piedra from a wig. -Roben Horst, first isolated the fungus, named Pleurococcus beigelii -In 1901, black variety of this disease was discovered by Malgoi-Hoes -In 1911, Horta, independence of ethilogical agents of white & balck piedra -1928, Area Leao & Fonseca, Piedra hortae, black piedra

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9 Infected hair (White piedra)

10 White Piedra, hair nodule

11 GEOGRAPHIC DISTRIBUTION (WHITE PIEDRA) -The condition is worldwide in distribution -More common in tropical and subtropical regions.

12 THE CAUSAL ORGANISMS (WHITE PIEDRA) -Trichosporon Spp, may be result from synergy between the fungi & coryneform bacteria -Basidiomycetous arthroconidial yeasts genus -Trichosporon Spp are also agents of cutaneous and systemic infections (in neutropenic patients) -Most important species: -T. asahii (formerly T. beigelli), T. mucoides and T. inkin: most frequently, systemic infection -T. asteriodes and T. cutaneum: generally, superficial skin infections -T. ovoides: generally causes white piedra of the scalp -T. inkin: generally causes white piedra of the pubic hair

13 THE ORGANISM HABITAT (WHITE PIEDRA) -Widespread natural distribution -Soil, water, on plants -Common commensal inhabitants of the skin and gastrointestinal tract in humans

14 EPIDEMIOLOGY (WHITE PIEDRA) -Trichosporon Spp: part of the normal skin flora of human -Mostly endogenous in origin -Shared cosmetics or lotion -Both men and women of all ages -Most common in young adults

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16 CLINICAL MANIFESTATIONS (WHITE PIEDRA) -Irregular, soft, white or light brown nodules (d:1-1.5mm) 1.5mm) along the hairs -Nodules: mainly located on the distal half of the hair shaft. -Usually the hairs are not invaded. -Nodules: can usually be detached. -Uncovered part of the hair shafts: Unaffected -Underlying skin: Unaffected - Usually no broken hairs. But may break if the fungi have been there for long periods * -More commonly affects pubic hair, beards, mustaches and eyebrows and/or eyelashes. Less: scalp hair * -In immunocompromised patients: frequently cutaneous dissemination (necrotic papules and nodules), Less: systemic dissemination

17 DIFFERENTIAL DIAGNOSIS (WHITE PIEDRA) -Pediculosis -Trichomycosis axillaris -Monilethrix Trichoptilosis -Trichorrhexis nodosis

18 LABORATORY DIAGNOSIS (WHITE PIEDRA)

19 MICROSCOPIC EXAMINATION (WHITE PIEDRA) Preparation of infected dhairs with 10% KOH or lactophenol: l nodules consist of septate hyphae, arthrospores and blastospores *

20 Microsopic feature, Trichosporon sp: (A)blastoconidia; (B) arthroconidia

21 Microsopic feature, Trichosporon sp.

22 Microsopic feature, Trichosporon sp.

23 CULTURE (WHITE PIEDRA) -Sensitive to cyclohexamide -Inoculation of hairs on to the "SC" plates Stored at C -Within 2-10 days: White to cream heaped colonies * -Teased mount: hyaline mycelium m fragmented into rectangular, oval or round arthrospores plus budding blastospores -All species are easily identified by commercially available carbohydrate assimilation assays

24 Trichosporon sp, culture at 25 0 C.

25 Trichosporon sp.

26 TREATMENT (WHITE PIEDRA) -Shaving or clipping i the hairs -Topical clotrimazole cream -Relapse -Oral itraconazole (100 mg/day for 8 weeks) for scalp hair

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28 BLACK PIEDRA Definition: -An Uncommon fungal infection of hair with Small, dark brown to black, hard, adherent nodules on the distal portion of the scalp hair shafts which are thicker (UP to 150 μm) at one and. -Sometimes also occur at the other sites

29 Infected hair (Black Piedra)

30 Black Piedra, hair nodule

31 Black Piedra, hair nodule

32 GEOGRAPHICAL DISTRIBUTION (BLACK PIEDRA) In humid tropical of South and Central America, South East Asia and Africa

33 THE CAUSAL ORGANISM & HABITAT (BLACK PIEDRA) -Piedra hortae, mould, mixed with coryneform bacteria, occasinally with Trichosporon spp * -Ascomycete -Cuticule penetration -Mammalian hair

34 EPIDEMIOLOGY (BLACK PIEDRA) -Young adults of both sexes -Slight predominance among men -Reports of epidemics in families Communities -The common use of combs, hair brushes -Application of plant oils to the scalp hair, predispose to the condition

35 CLINICAL MANIFESTATIONS (BLACK PIEDRA) -Affected hairs: from 4 to 8 (or more) firmly attached nodules, (d: 1-2mm) -Nodules: Oval or elongated, hard, dark brown to black, may surround the hair -Uncovered part of the hair shafts: Unaffected -Underlying skin: Unaffected -Often, broken hairs -While brushing, may hear a metallic sound

36 DIFFERENTIAL DIAGNOSIS (BLACK PIEDRA) -Trichorrhexis nodosa -Trichonodosis -Pediculosis (itching is usually absent in black piedra)

37 LABORATORY DIAGNOSIS (BLACK PIEDRA)

38 MICROSCOPIC EXAMINATION (BLACK PIEDRA) -Unique: completion of their entire lifestyle on hairs of living human, production of sexual spores in it s parasitic phase -Preparation of infected hairs with 10% KOH or lactophenol: a -Preparation of infected hairs with 10% KOH or lactophenol: a packed mass of brown pigmented branching hyphae surrounding asci, each of which holds eight ascospores

39 Piedra hortae, microscopic features. Dark, thick-walled septate hyphae, swollen cells resembling chlamydospores Piedra hortae, fusiform ascospores from crushed nodule

40 CULTURE (BLACK PIEDRA) -Resistant to cyclohexamide -Implantation of hair fragments on to the "SCC" plates stored at RT -After 2-3 weeks: dark brown to black colonies with folded surface and a flat margin -Teased mount: thick-walled, septate, branched pigmented hyphae, clamydochonidia, ascus and ascospore may be seen

41 Piedra hortae

42 Piedra hortae

43 Piedra hortae

44 TREATMENT (BLACK PIEDRA) -Clipping i the hairs -Using topical salicylic acid preparation -Using topical imidazole cream -Application of topical selenium sulphide -Relapse may be acured

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46 Definition: TINEA NIGRA -A rare, chronic fungal infection of the stratum corneum, -Not extend to stratum lucidum -Brown to black klesions (Macules), have mild scale -Pigmentation is more intense near the border -Often affects the palms -Less commonly the soles -Synonyms: y Pityriasis nigra, Tinea nigra palmaris, Superficial pheohyphomycosis, Keratomycosis nigricance, -In 1890s, Cerqueira first described tinea nigra who named it keratomycosisnigricans i i palmaris

47 Tinea nigra

48 GEOGRAPHICAL DISTRIBUTION (TINEA NIGRA) -More common in tropical and subtropical regions

49 THE CAUSAL ORGANISM & HABITAT (TINEA NIGRA) - Phaeoannellomyces werneckii (also called Hortaea werneckii or Exophiala werneckii) -Dematiaceous (Melanized, brown-pigmented) mould -P. werneckii exhibits lipophilic adhesion to human skin -P. werneckii receives nourishment from the composed lipidsid -Tolerance to high salt concentration and low ph result in grow strong in human skin in areas with an increase concentration of sweet glands -Saprob founds in the soil and in decomposing vegetation

50 EPIDEMIOLOGY (TINEA NIGRA) -Thought to follow traumatic inoculation, 10 to 15-day incubation period -Most common in children and young adults -Hyperhidrosis: predispose to the condition -Reports of familial infections -No seemed to be contagious

51 CLINICAL MANIFESTATIONS (TINEA NIGRA) -Most commonly on the palm -Less frequently the sole or other sites -The macular lesion consists of one or several, flat, dark brown to black, non-scaling patches with a well- defined rim -Absence of inflammation -At first: very small patches -Later: expanded, become confluent, forming polycyclic or irregularly contoured lesions -Irregularly distributed pigmentation over larger lesions -Asymptomatic disease

52 Tinea nigra

53 Tinea nigra

54 DIFFERENTIAL DIAGNOSIS (TINEA NIGRA) May be confused with a variety of other diseases: -Nevi -Malignant melanoma -Chemical stains (Such as silver nitrate) -Syphilis, Addison s disease, *

55 Palmar Lichen Planus Mimicking Tinea Nigra Before & After 6 Weeks Treatment with Topical Steroids

56 LABORATORY DIAGNOSIS (TINEA NIGRA)

57 MICROSCOPIC EXAMINATION (TINEA NIGRA) Preparation of scrapings from the margin of a lesion with 10% KOH: irregular, branched, Septate, brown hyphae with ellipsoidal cells, often have a thick median cross-wall (2-celled yeast) Differentiation with dermatophytes: brown hyphae, more branched, thinness the end of hyphae, h yeast-like cells, clamydoconidia

58 Phaeoannellomyces werneckii, culture mount. Doublet yeast-like cells, septate hyphae.

59 Phaeoannellomyce s werneckii, culture mount. Doublet yeast-like cells, septate hyphae. *

60 Phaeoannellomyces werneckii *

61 CULTURE (TINEA NIGRA) -Sensitive to cyclohexamide -Inoculation of scrapings on "SC" plates Stored at C -Within 2-7 week: olive-black colonies of P. werneekii *

62 Phaeoannellomyces werneckii

63 TREATMENT (TINEA NIGRA) -As it is a very superficial infection (only the stratum corneum of the skin), simple scraping or abrasion can be curative - Keratolytics: benzoic acid and salicylic acid compound ointment (whitefield's ointment, 5% to 10% salicylic acid ointment) thiabendazolesolution l ti applied twice a day for several weeks -Disappearance of most lesions within 2-4 weeks, treatment should be continued for at least 3 weeks to avoid recurrence. -Topical imidazoles -Do not respond to griseofulvin *

64 Thanks for your attention