Jeremy McCourt, Pharm.D. 04/21/2011 Tinea and Dermatitis
Distinguish the clinical presentation and predisposing factors for tinea and dermatitis. Determine when should be treated with self-care management or referred due to exclusions. Determine the type of skin disorder and develop an appropriate treatment plan, when given specific patient information. Objectives
Penetration of keratinous structures of body by dermatophytes • 3 most common dermatophytes • Trichophyton • Microsporum • Epidermophyton • Can be contracted through contact with infected people, animals, soil, or fomites Etiology
Inoculation of dermatophyte into skin • Incubation • Grows in stratum corneum • Minimal signs of infection • Enlargement • Size and duration of infection depend on fungal growth rate and epithelial turnover rate • Dermatophytes produce keratinases that cause allergic reactions in living epidermis • Refractory period • Time preceding cell-mediated immune response • Inflammation and pruritis are at their peak • Involution • Symptoms diminish, infection may clear spontaneously Pathophysiology
Predisposing Factors • Impairment of immune system • Poor nutrition and hygiene • Impaired circulation • Immune system depression • Diabetes mellitus and other debilitating diseases • Promotion of fungal growth • Skin occlusion • Warm, humid climates • Skin trauma
Presenting symptoms vary depending on site of infection • Ranges from mild itching and scaling to severe, exudative inflammatory process • Denudation • Fissuring • Crusting • Discoloration of affected skin Signs/Symptoms
Secondary infections Permanent hair loss Scarring Complications
“Athlete’s foot” • Malodor, pruritis, and/or stinging sensation on the feet • Typically involves lateral toe webs, usually between 3rd and 4th, or 4th and 5th toes • Infection may spread to sole or instep of the foot, but rarely to the dorsum Tinea pedis
Tineapedis - Fissuring, scaling, or maceration of interdigital spaces www.wrongdiagnosis.com www.webmd.com
“Onychomycosis” Nails lose normal, shiny luster and become opaque Can NOT be treated with topical non-prescription drugs Tineaunguium
Tineaunguium • - Thick, rough, yellow, opaque, and friable • - Nail may separate from nail bed, and may be lost altogether www.mupeg.com www.skincareguide.com
“Ringworm of the body” • Most common in prepubescent individuals • Frequently transmitted among children in day care centers • Increased risk in hot, humid environments • Stress and overweight also increase risk of infection • Can occur on any part of the body, on smooth bare skin • May have diverse presentation Tinea corporis
TineaCorporis • - Begin as small, circular, scaly, erythematous areas • - Spread peripherally • - Borders may contain vesicles or pustules www.webmd.com
“Jock itch” • More common in males • Affects medial and upper parts of thighs and pubic area • Penis and scrotum are usually not affected • Generally occurs bilaterally with significant pruritis • Well-demarcated margins Tineacruris
Tineacruris • - Slightly elevated, more erythematous than central area; fine scaling and small vesicles may be seen • - Acute lesions are more bright red, where chronic cases have more of a hyperpigmented appearance www.naturalskinrepair.com www.healthhype.com
“Ringworm of the scalp” • More common in children • Occurs more frequently in black females than black males and white children • Can be spread by direct contact, but more commonly through contact with infected fomites • Can be spread through contact with infected cats or dogs Tinea capitis
Non-inflammatory • Small papules surrounding hair shafts, spread centrifugally • Little inflammation, hair in lesions is dull gray in color, usually breaks off at level of scalp • Inflammatory • Inflammation with weeping, crusty patches on scalp • Black-Dot • Infected areas of scalp from breakage of hair shafts • Favus • Patchy area of hair loss with yellowish crusts and scales • Can lead to scalp atrophy, scarring, and permanent hair loss Tinea capitis Cont.
Tinea capitis elsevierimages.com www.webmd.com accessmedicine.ca accessmedicine.ca
“Barber’s itch”, “Ringworm of the beard” Affects the hairs and follicles of beards and mustaches Removal of the beard or mustache is recommended Tineabarbae www.aafp.org www.unloc-aging.com
QUickly and accurately assess the patient • SCHOLAR – Symptoms, characteristics, history, onset, location, aggravating factors, remitting factors) • Establish that the patient is appropriate for self-care • Suggest appropriate self-care strategies • Talk with the patient Treatment Approach (QuEST)
Causative factor unclear • Unsuccessful initial treatment, or worsening of condition • Nails or scalp involved • Face, mucous membranes, or genitalia involved • Signs of possible secondary bacterial infection (oozing purulent material) • Excessive and continuous exudation • Condition extensive, seriously inflamed, or debilitating • Diabetes, systemic infection, asthma, immune deficiency • Fever, malaise, or both Exclusions for Self Treatment
Provide symptomatic relief Eradicate existing infection Prevent future infections Goals of Treatment
Avoid occlusive clothing and fabrics Keep area clean and dry Limit exposure to affected area Do not share or re-use clothing, towels, or other personal items Non-Pharmacologic Treatment
Topical antifungals can be used to treat most infections and are considered first line • Available in creams, ointments, powders, and solutions • Systemic (oral) therapy may be needed for infections involving nails or hair Pharmacologic Treatment patient.co.uk
Common: GI, dermatologic, headache • Less common: taste disturbance, fatigue, inability to concentrate, abnormal liver enzymes • Terbinafine • Avoid in patients with chronic or active liver disease • May cause Stevens-Johnson’s Syndrome • Itraconazole • Avoid in patients with active liver disease • Avoid in patients with ventricular dysfunction (CHF) Adverse Effects
Terbinafine • Inhibits CYP 2D6 • Medications: tricyclic antidepressants, psychotropic drugs, cimetidine, rifampin, cyclosporine, caffeine, theophylline, terfenadine • “Azoles” • Inhibit CYP 3A4 • Medications: benzodiazepines, warfarin, simvastatin Drug Interactions (Oral agents)
Proper application technique for topical agents to prevent over- or under-medication Patient should know the expected duration of therapy Apply medication regularly throughout the complete course of treatment Methods to prevent recurrent infections Patient Counseling
A.B. is a 21 y/o WM college student who complains of burning, itching sensation between the toes of his left foot. His symptoms are worse each day, and are worse at bedtime. The area between his toes is very red and becomes worse after showering. He describes his toenails as normal in appearance; no discoloration or brittleness. He has no concurrent medical conditions or medications. A.B. showers daily in his residence hall and at the gym after workouts. He also reports that his feet sweat a lot. Case
What type of infection is A.B. likely suffering? What are the exclusions for self-treatment for this patient? What should you do to correct A.B.’s current problem? What counseling would you provide to A.B.? Case Cont.
Inflammation of the skin • Creates a vicious cycle of itching and scratching • Condition is chronic and relapsing • No absolute known cause • Believed to be caused by genetic, environmental, and immunologic mechanisms Characteristics
Intense itching Erythematous inflamed lesions Papules and vesicles present Lesions associated with scratching, which leads to excoriations and exudates Most commonly extensor surfaces of extremities, trunk, face, scalp, and neck Signs/Symptoms
Dermatitis health.allrefer.com www.webmd.com
Pruritus with three or more of the following: • History of flexural dermatitis of the face in children < 10 years of age • Self and/or family history of asthma or allergic rhinitis • History of generalized xerosis within the past year • Visible flexural eczema • History of rash at younger than 2 years of age Diagnosis
Allergen triggers • Food allergens • Especially in younger patients with severe condition • Aeroallergens • Various other allergens (pet dander, dust mites, grass, pollen) Predisposing Factors
Increased susceptibility to microbial skin infections (Staph. aureus) Increased risk of herpes simplex infection Eyelid dermatitis (blepharitis), nipple dermatitis, cheilitis of the lips Blepharitis may result in visual impairment due to corneal scarring Complications
Identify and eliminate potential allergens • Reduce frequency of bathing to every other day • Use tepid water in baths • Avoid irritating soaps, washcloths, or scrubs • Air dry skin and gently pat dry • Apply emollient within 3 minutes of drying • Keep fingernails short and clean to prevent scratching • Consider wearing cotton gloves at night • Use cotton sheets and pajamas • Avoid harsh laundry detergents • Moisturize at lease twice a day Non-Pharmacological Treatment
Topical Steroids • Various strengths and formulations • High potency steroids should be used for short periods of time (< 3 weeks) • Do NOT use on the face, mucous membranes, eyelids, or skin-fold areas • Moderate potency agents can be used for more chronic dermatitis of the trunk or extremities • Low potency agents are typically used for children Pharmacologic Treatment
Corticosteroid potency Adapted from LexiComp,Inc.
Antipruritics • Local anesthetics • Pramoxine, lidocaine, benzocaine • Antihistimines • May be due to sedative effects or antihistamine activity • Topical agents (diphenhydramine) should not be used OTC for more than 7 consecutive days. Pharmacological Treatment Cont.
Topical Immunomodulators • Long-term option • Can be used on all body locations for prolonged periods w/out skin atrophy • Reduces the inflammatory process of dermatitis through inhibition of calcineurin • Agents: • Tacrolimus 0.03% and 0.1% ointment • Used for moderate to severe dermatitis • 0.03% approved for children > 2 years old • Pimecrolimus 1% cream Pharmacologic Treatment Cont.
Coal Tar Preparations • Contain both antipruritic and antiinflammatory properties • Used in combination with corticosteroids to reduce the strength of steroid needed • Should not be used on oozing lesions due to stinging and irritation • Limiting factors include strong odor and staining Pharmacologic Treatment Cont.