Presentation on theme: "Fungal Infection of the Skin Dr. Mohamad Nasr Lecturer Of Dermatology & Venereology."— Presentation transcript:
Fungal Infection of the Skin Dr. Mohamad Nasr Lecturer Of Dermatology & Venereology
Topics Covered Tinea infections with special attention to scalp, feet and nails Basic diagnostic techniques – KOH – Culture – Woods light Differentials to consider. Basic Treatment Tinea Versicolor Candidiasis
Dermatophytosis “Ringworm" disease of the nails, hair, and/or stratum corneum of the skin caused by fungi called dermatophytes.
Etiological agents Microsporum - infections on skin and hair (not the cause of TINEA UNGUIUM) Epidermophyton - infections on skin and nails (not the cause of TINEA CAPITIS) Trichophyton - infections on skin, hair and nails.
Clinical manifestations of ringworm Infections named depending on location of infection.
Tinea capitis; ringworm infection of the scalp. Tinea corporis; ringworm infection of the body (smooth skin) Tinea cruris; ringworm infection of the groin. Tinea unguium; ringworm infection of the nails. Tinea barbae; ringworm infection of the beard. Tinea manuum; ringworm infection of the hand. Tinea pedis; ringworm infection of the foot (athlete's foot).
Tinea corporis - body ringworm Skin lesion pink-red, scaly, annular patch with expanding border (active border).
Tinea cruris - ringworm of the groin
Tinea capitis - ringworm of the scalp Types: 1. Scally. 2. Black dot. 3. Favus. 4. Kerion.
Black dot type;
Favus; caused by T. schoenleinii.
Tinea Capitis Treatment Must treat hair follicle Topical not effective Systemic agents Griseofulvin for children ;12.5 mg/kg. Imidazoles, terbinafine. Steroids for inflamed lesions like Kerion. Treat until no visual evidence, culture (-)… plus 2 weeks Average of 6-8 weeks of treatment.
Other oral anti-fungal for patients who do not tolerate or respond to Griseofulvin. Terbinafine (Lamisil) 3 to 6mg/kg once a day for 2 to 4 weeks. Fluconazol: 6mg/kg/day once daily for 6wk Itraconazole: 5mg/kg/day,once daily or divided into two doses,for 2 to 4 weeks
Tinea pedis - Athletes' foot infection Between toes or toe webs - 4th and 5th toes are the most common. Types; 1. Interdigital type. 2. Hyperkeratotic type. 3. Vesiculobullous type.
Tinea Pedis: Treatment Dry Feet Alternate shoes, Absorbent powders, Change socks Scale my be reduced with keratolytic Topicals and/or Systemics. Topical: terbinafine may be more effective than azoles. Steroids if inflamed. Systemic allyamines or azoles
Onychomycosis 15-20% of those between yrs. infected. No Spontaneous remissions General Appearance: – Typically begins at distal nail corner – Thickening and opacification of the nail plate – Nail bed hyperkeratosis – Onycholysis – Discoloration: white, yellow, brown – Edge of the nail itself becomes severely eroded. Some or all nails may be infected
Tinea unguium - ringworm of the nails
Onychomycosis Types: 1. Distal Subungal 2. White superficial Chalky white patches 3. Proximal Subungal May indicate HIV infection 4. Total dystrophic
Onychomycosis with Onycholysis
Candidaisis of nail Paronychia
Psoriasis Middle of nail, oils spots, pitting.
Treatment of Onychomycosis. Topical Treatment: Can be effective for limited involvement and for prevention.
Treatment of Onychomycosis Oral therapy Effective. Relapse rate % in one year. Lamisil 250mg. 6 weeks/12 weeks. Baseline labs and one month. CBC (neutropenia), Liver function. Itraconazole. Pulse dosing fingernails - (200 mg bid 1 wk q mo.) x 2
Diagnostic Tests KOH Preparations – A slide. – Scrape border of lesion. – Apply 1-2 drops of KOH 20% and heat gently – Examine at 40x – Look for hyphae
Fungal Cultures DTM (Dermatophyte Test Medium) – Yellow to red is (+). Sabouraud’s agar Media
Wood’s Light – Tinea Capitis Blue green florescent with M. Canis. Not useful for Trichophyton (Most Common) – Other Areas: Useful to diagnose as erythrasma (coral red/pink). Tinea versicolor may be pale yellow. Less helpful if patient recently bathed.
Tinea Versicolor Numerous, well-marginated, oval-to-round macules with a fine white scale when scraped. Pigmentary alteration uniform in each individual. – Red – Hypo pigmented – Hyperpigmented Scattered over the trunk and neck. Seldom the face. Pityrosporum orbicularis, M. furfur – Normal flora of skin Asymptomatic.
Tinea Versicolor - Differential Vitiligo Pityriasis Alba Pityriasis Rosea
Vitiligo White without scale.
Pityriasis Alba Frequently on face, KOH neg. Few lesions. May have fine white scale.
Pityriasis Rosea Papules or plaques with Collarette of scale, KOH (-), Woods light neg.
Tinea Versicolor Diagnosis: Scrape lightly – fine white scale KOH Positive for short hyphae and spores (Spaghetti and meatballs) Woods Light – pale yellow white fluoresce. Culture rarely done.
Tinea Vesicolor – Woods Light Yellow White
Tinea Versicolor Microscope
Tinea Versicolor-Treatment Topical; for limited involvement. Selenium Sulfide Shampoos: lather 10 minutes wash off x 7 days. Ketoconazole 2% shampoo: 5 minutes 1-3 days. Imidazoles topicals to body qd-bid for 2-4 wks. Terbinafine spray.
Tinea Versicolor-Treatment Oral; for extensive Itraconazole: 200 mg for 7days Fluconazole: 300 mg once Ketoconazole: 200 mg for 10 days
Notes Hypopigmentation resolves slowly No scale when scraped indicates cure. Sunlight helps restore pigment Prophylaxis before summer in some patients. Selenium shampoo’s Tinea Versicolor-Treatment
Candidiasis Candida Albicans Normal Flora Occurs in moist areas especially where skin touches. Presentation: primary lesion is a red pustule. Most Common: pustules dissect horizontally through the stratum corneum leaving a red, glistening denuded surface with long continuous border with satellite lesions.
Candidiasis Immunosuppression of any type (disease, steroids, D.M. or Antibiotics ). Diagnosis: History of predisposing factors and/or classic appearance of lesions at typical locations.