Fungal Skin Infection Y4 Lincoln 2024 PDF
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Uploaded by TenaciousConflict
Lincoln University College
2024
Lincoln
Dr Zulrusydi Bin Ismail
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Summary
This document is a presentation on fungal skin infections, covering various types, sources, diagnosis, and treatments. It includes information about superficial, subcutaneous, and systemic mycoses, as well as details about the fungi involved and common presenting symptoms.
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Fungal skin infections DR ZULRUSYDI BIN ISMAIL BASIC ANATOMY OF THE SKIN 1) EPIDERMIS 2) DERMIS The fibrous connective tissue or supportive layer of the skin The dermis contains the following: - Blood vessels - Lymph vessels - Hair follicles - Sweat gla...
Fungal skin infections DR ZULRUSYDI BIN ISMAIL BASIC ANATOMY OF THE SKIN 1) EPIDERMIS 2) DERMIS The fibrous connective tissue or supportive layer of the skin The dermis contains the following: - Blood vessels - Lymph vessels - Hair follicles - Sweat glands - Collagen bundles - Fibroblasts - Nerves - Sebaceous glands Fungal infections of the skin Superficial mycoses Stratum corneum Subcutaneous mycoses Dermis Subcutaneous tissue Deep skin mycoses Systemic mycoses Fungal infections of the skin 1. Superficial mycoses invade stratum corneum, hair and nails 2. Subcutaneous / Deep Skin mycoses invade the dermis or subcutaneous tissue due to implantation via injury 3. Systemic mycoses Deep (true pathogens) spread via blood or extension from nearby structures Opportunistic immunocompromised hosts Fungal infections of the skin 1. Superficial mycoses i. Dermatophyte infections Tinea infection ii. Malassezia Pityriasis (tinea) versicolor Malassezia (pityrosporum) folliculitis iii. Candida Oral candidiasis (oral thrush) Vulvovaginal candidiasis (vaginal thrush) Candida intertrigo (skin fold infection) Paronychia (nail fold infections) Chronic mucocutaneous candidiasis Fungal infections of the skin 2. Subcutaneous / Deep Skin mycoses i. Chromoblastomycosis ii. Mycetoma iii. Sporotrichosis 3. Systemic mycoses Blastomycosis Cryptococcosis Histoplasmosis Systemic mycoses Sources of fungi Endogenous fungi part of resident flora e.g. Candida, Malassezia Infection follows some change in host allowing fungus to change from saprophyte to parasite Exogenous true pathogenic fungi external sources: Animals (zoophilic) Soil (geophilic) Other humans (anthrophilic) Superficial Fungal infections of the skin Fungi causing superficial mycoses 1. Dermatophytes Trichophyton Microsporum Epidermophyton 2. Yeasts/Candida Candida skin infection 3. Malassezia Pityriasis (tinea) versicolor Malassezia (pityrosporum) folliculitis 4. Other Moulds e.g. Scopulariopsis, Scytalidium, Fusarium, Aspergillus Dermatophytoses Dermatophyte; a group of fungi capable of infecting non viable keratinized cutaneous structures including stratum corneum, nails, and hair. Dermatophytoses Further specified according tissue involved; Epidermomycosis → epidermal dermatophytosis Trichomycosis → dermatophytosis of hair and hair follicles Onychomycosis →dermatophytosis of the nails apparatus. Dermatophytes infection of the skin called ‘Tinea’ followed by appropriate body part (in Latin) Tinea corporis body Tinea pedis feet Tinea cruris groin Tinea capitis scalp Tinea faciei face Tinea unguium nail Tinea manuum hand Tinea barbae beard/moustache Tinea incognito atypical dermatophyte infection altered by use of steroids Tinea corporis (body) Tinea corporis at the thigh Tinea corporis / tinea glutealis Tinea corporis Sharply demarcated, erythematous plaques at the butock. Tinea corporis (body) annular well demarcated raised border central clearing lesion Tinea corporis?? - a 1-month history of a pruritic weeping lesion on her right leg, which started after scratching over this pruritic area - pruritic coin-shaped patches on the skin Dx : Discoid Eczema / Nummular dermatitis - a 1-month history of a pruritic weeping lesion on her right leg, which started after scratching over this pruritic area - pruritic coin-shaped patches on the skin Tinea corporis?? psoriasis Tinea Pedis Tinea pedis : interdigital dry type. Tinea pedis: interdigital macerated The interdigital space between the toes type shows erythema and scaling Tinea Pedis Tinea pedis : moccasin type Tine pedis : moccasin type - fairly sharply marginated erythema -well demarcated erythema on the of the plantar foot with mild dorsum of the foot. keratoderma. Tinea Pedis Tinea pedis: bulous type- presence of blister> ruptured and lead to erosion Tinea cruris Confluent, erythematous, scaling plaques o the medial thighs, inguinal folds, and pubic area. Raised margin and sharply marginated. Tinea Facialis/ Faciei Sharply marginated, erythematous, scaling, and crusted plaques with central clearance on te face. Tinea Facialis? Tinea manuum Dry non silvery scaly erythematous Erythema and scaling of the right hand lichenified and eczematous plaques “The onehand, two-fet “ distribuition is typical of epidermal dermatophytosis of the hands and feet. a dermatophyte causes toenail fungus Dermatophytes cause 90% of toenail fungal infections. Tinea barbae Scattered, discrete follicular pustules and papules in the moustache area, easily mistaken for s.aureus folliculitis. Tinea capitis A large round, hyperkeratotic A green fluorescence when examined plaque of alopecia due to breaking with a wood’s lamp. off of the hair shafts. Tinea capitis A large round, hyperkeratotic plaque of alopecia due to breaking off of the hair shafts. KERION Painful boggy, purulent inflammatory nodule on the scalp. The lesion drain pus from multiple openings and there is retroauricular , tender lymphadenopathy. KERION A kerion is an abscess caused by fungal infection. It most often occurs on the scalp (tinea capitis), but it may also arise on any site exposed to the fungus such as face (tinea faciei) and upper limbs (tinea corporis). It is often misdiagnosed as bacterial infection. Enlargement of the regional lymph nodes can occur, and some people become systemically unwell with fevers and malaise. It may be followed by a widespread itchy eczema-like rash (dermatophytide). KERION A kerion is caused by dramatic immune response to a dermatophyte fungal infection (tinea). The most common fungi found in kerion are: Microsporum canis Trichophyton tonsurans Trichophyton verrucosum Trichophyton mentagrophytes Trichophyton rubrum is not a common cause of kerion. Dermatophytoses: Lab investigations Direct Microscopy Skin: collect the scales with no 15 scalpel blade Place on the microscope slide > cover with a cover slip. Preparation of sample: KOH 5-20% solution is applied at the edge of coverslip. Lab investigations Wood’s lamp Lab investigations Skin for Fungal culture - specimens collected from scaling skin lesions, hair and nails – place into the culture plate-culture on Sabauroud’s glucose medium. Lab investigations Skin Biopsy (Dermatopathology) - PAS ( Periodic acid-schiff ) stain to indentify the fungal element. Periodic acid-Schiff’s (PAS) stain revealing PAS-positive septate fungal hyphae with irregular swellings (X400) Treatment Topical antifungal preparations Clotrimazole Miconazole Ketoconazole Econazole Imidazole Allyamines Terbinafine Naftifine Naphthionates tolnaftate SYSTEMIC ANTIFUNGAL FOR TINEA CAPITIS Griseofulvin Fluconazole adult: 250mg bd till hair growth adult : 150mg once a week 4-6 child: 20-25mg/kg/day - 8- week 10week child: 5mg/kg/day 4-6week Itraconazole Terbinafine adult: 200mg od 4-6 weeks adult: 250mg od 4weeks child: 5mg/kg/day in divided dose child: bd 4-6 week wt 10-20kg 62.5mg/day 2-4weeks wt 20-40kg 125mg/day 2-4weeks wt >40kg 250mg/day 2-4weeks SYSTEMIC ANTIFUNGAL FOR TINEA PEDIS Griseofulvin Terbinafine 1000mg od 4-8weeks 250mg OD for 2 week child: 10-20mg/kg od 4-8weeks child Itraconazole wt 10-20kg 62.5mg/day 2-4weeks 200mg bd for 1 week then 200mg od wt 20-40kg 125mg/day 2-4weeks 2 weeks wt >40kg 250mg/day 2-4weeks child: 3-5mg/kg per day for 2 weeks SYSTEMIC ANTIFUNGAL FOR OTHER TYPES OF SUPERFICIAL FUNGAL INFECTIONS Itraconazole Griseofulvin 200mg OD for 1-2 weeks, adult :500mg OD or BD 2-4 weeks, child 3-5mg/kg od 1week child: 10-20mg/kg od 2-6weeks Fluconazole Terbinafine adult : 150mg once a week 2-4week Adult:250mg OD for 2 weeks , child child: 6mg/kg once a week 2-4week wt 10-20kg 62.5mg/day 2-4weeks wt 20-40kg 125mg/day wt >40kg 250mg/day 2-4weeks Pityriasis versicolor (a.k.a Tinea versicolor) A chronic asymptomatics scaling epidermomycosis associated with superficial overgrowth of the hyphal form of Malassezia furfur. Characterized by well- demarcated scaling patches with variable pigmentation. Occurring most commonly on the trunk. Etiology M.furfur ( Pityrosporum ovale, P.orbiculare) Round yeast and elongated pseudohyphal forms, so-called “spaghetti and meatballs” Age of onset: young adult - Less common when sebum production is reduced or absent. Predisposing factors: - High temperature/relative humidity,oily skin, hyperhidrosis, hereditary factors, and immunodeficiency. Pityriasis versicolor Multiple, small-to-medium sized, well-demarcated hypopigmented macules on the back. Lab examination Direct microscopic examination Wood’s lamp -Blue-green fluorescence of the scales. Dermatopathology: - Budding yeast and hypals form in the most superficial layers of the stratum corneum, seen best with PAS stain. Diagnosis Clinical findings Confirmed by positive KOH preparation findings. Skin Biopsy Treatment Topical antifungal preparations Clotrimazole Miconazole Ketoconazole Econazole Imidazole Allyamines Terbinafine Naftifine treatment Topical agents - Selenium sulphide 2·5% (SELSUN) (apply daily for 1week for 10-15min) - ketoconazole 2% shampoo - miconazole, clotrimazole, ketoconazole, econazole cream bd for 2 weeks - terbinafine 1% solution bd 1week Systemic therapy - Itraconazole 200 mg/day for 7-14 days - Fluconazole 400mg stat, repeat in 1 week Dermatophytes infection of the skin called ‘Tinea’ followed by appropriate body part (in Latin) Tinea corporis body Tinea pedis feet Tinea cruris groin Tinea capitis scalp Tinea faciei face Tinea unguium nail Tinea manuum hand Tinea barbae beard/moustache Tinea incognito atypical dermatophyte infection altered by use of steroids Tinea unguium / NAIL ONYCOMYCOSIS Tinea unguium is most often due to Trichophyton rubrum and T. interdigitale. I t s h o u l d b e d i s t i n g u i s h e d f ro m o t h e r c a u s e s o f onychomycosis: Candida species, which often cause paronychia Moulds including Scopulariopsis brevicaulis, Fusarium spp., Aspergillus spp., Alternaria, Acremonium, Scytalidinum dimidiatum and Scytalidinium hyalinum Tinea unguium Tinea unguium is increasingly prevalent with increased age and spreads from tinea pedis or less often, tinea manuum. It may affect one or more toenails and/or fingernails and most often involves the great toenail or the little toenail. It is often confused with non-infected nail dystrophy due to skin disease, particularly psoriasis (also dermatitis, lichen planus, viral warts, ageing changes). CAUSES OF FUNGAL NAIL INFECTION Onychomycosis can be due to infection with dermatophytes or non- dermatophytes such as moulds and yeasts. Dermatophytes (over 75% of cases) Trichophyton spp Non-dermatophyte Moulds (10% of cases) eg. Aspergillus species, Scopulariopsis species, Fusarium species Yeasts (uncommon) ; Candida albicans, and rarely non-albicans candida yeasts Patterns of nail infection (onychomycosis) Distal & lateral subungual ( DLSO ) Proximal subungual ( PSO ) clinical features of onychomycosis Superficial white (SWO) Total dystrophic (TDO) NAIL ONYCOMYCOSIS A subtype of onychomycosis caused by the dermatophyte group of fungi. Classification of the anatomic patterns of onychomycosis: 1) Distal & Lateral Subungual Onychomycosis (DLSO) -T. rubrum 2) Superficial White Onychomycosis (SWO) -T. mentagrophytes 3) Proximal Subungual Onychomycosis (PSO) - T. rubrum,T megnenii, T. schoenleinii 4) Total Dystrophic Onychomycosis (TDO) Who gets fungal nail infections? Onychomycosis is common in older aged adults (over 65 years), diabetics, immunocompromised patients (especially those with HIV disease and athletes. Onychomycosis may be present amongst family members due to autosomal inheritance (HLA-DR8) or environmental factors. It rarely occurs in children. Other associated comorbidities include: Tinea pedis. Tinea manuum , Psoriasis and peripheral vascular disease, venous insufficiency , hallux valgus, smoking, asymmetric gait nail unit syndrome, Down Syndrome, and obesity. AETIOLOGIC FACTORS: -Wearing of occlusive footwear -overcrowding -communal bathing areas TRANSMISSION -transmitted from one to another by fomite or direct contact, commonly within family members. Lab investigations Nail scrapping for Direct Microscopy Skin: collect the scales with no 15 scalpel blade Place on the microscope slide > cover with a cover slip. Preparation of sample: KOH 5-20% solution is applied at the edge of coverslip. Lab investigations Nail clipping Fungal culture - specimens collected from nails – place into the culture plate-culture on Sabauroud’s glucose medium. Lab investigations Nail Biopsy (Dermatopathology) - PAS ( Periodic acid-schiff ) stain to indentify the fungal element. TREATMENT Mild infections affecting less than 80% of one or two nails may respond to topical antifungal medications but cure usually requires an oral antifungal medication. Fingernail infections are usually cured more quickly and effectively than toenail infections. TREATMENT Mild infections affecting less than 80% of one or two nails may respond to topical antifungal medications but cure usually requires an oral antifungal medication. Fingernail infections are usually cured more quickly and effectively than toenail infections. TREATMENT Topical antifungals nail lacquer amorolfine 5% ( loceryl) Ciclopirox 8% Ethyl lactate ( SFN10) nail drops - clotrimazole solution Topical antifungals are used twice weekly for 6 -12 months for nail plate infections: TREATMENT Systemic antifungals Fluconazole Griseofulvin Itraconazole Terbinafine Combination therapy: Studies show that taking antifungal pills and applying medicine to your nails can be more effective than using either treatment alone. TREATMENT TREATMENT TREATMENT Nail removal: For severe infection or other treatments just don’t work,may recommend removing the nail(s) to get rid of the infection. Nonsurgical nail removal (a chemical is applied to the nail) Surgical nail removal Fungi causing superficial mycoses 1. Dermatophytes Trichophyton Microsporum Epidermophyton 2. Yeasts / Candida Candida skin infection 1. Malassezia Pityriasis (tinea) versicolor Malassezia (pityrosporum) folliculitis 3. Moulds e.g. Scopulariopsis, Scytalidium, Fusarium, Aspergillus Majority of infections caused by Candida albicans Predisposing factors – diabetes, cancer, HIV infection, broad-spectrum antibiotic or corticosteroid therapy Affects skin and mucous membranes of mouth and vagina Clinical features – oropharyngeal candidiasis, vulvovaginal candidiasis, candida intertrigo, candidal paronychia, chronic mucocutaneous candidiasis Oral candidiasis Candidal paronychia Candida intertrigo Direct microscopic examination Budding yeasts with hyphae or pseudohyphae Culture Rapidly growing, smooth, soft, shiny, and cream in colour Mild cutaneous candidiasis Topical Miconazole 2%, Clotrimazole 1%, Tioconazole 1% cream Extensive cutaneous candidiasis Itraconazole 200mg OD for 1 week or Fluconazole 100mg OD for 1 week Oral candidiasis Nystatin suspension 500,000 units QID for 2 weeks Flucanazole 100mg OD for 1-2 weeks Fungal infections of the skin 2. Subcutaneous / Deep Skin mycoses i. Chromoblastomycosis ii. Mycetoma iii. Sporotrichosis 3. Systemic mycoses Blastomycosis Cryptococcosis Histoplasmosis Systemic mycoses THANK YOU