Dermatophyte (tinea) infections

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How is tinea capitis treated?

Systemic antifungal treatment is the standard of care for children with tinea capitis. The systemic antifungal therapies for tinea capitis include griseofulvin, terbinafine, fluconazole, and itraconazole. Griseofulvin has a long history of use for childhood tinea capitis and is a well-accepted first-line therapy. -Oral griseofulvin and oral terbinafine are the most commonly used therapies for tinea capitis in children.

What is tinea corporis?

Tinea corporis is a cutaneous dermatophyte infection occurring in sites other than the feet, groin, face, or hand.

What is tinea cruris?

Tinea cruris (also known as jock itch) is a dermatophyte infection involving the crural fold.

How is Majocchi's granuloma treated?

Topical antifungals are unlikely to penetrate deeply enough to effectively treat Majocchi's granuloma. Treatment with an oral antifungal is recommended.

How is tinea cruris diagnosed?

A potassium hydroxide (KOH) examination of scales scraped from tinea cruris will show the segmented hyphae characteristic of dermatophyte infections. The highest yield is obtained from skin scrapings taken from the active border.

How is tinea corporis diagnosed?

A potassium hydroxide (KOH) preparation will show the segmented hyphae characteristic of dermatophyte infections. The highest yield is obtained from skin scrapings taken from the active border of a plaque.

What are dermatophyte infections?

Dermatophyte infections are common worldwide, and dermatophytes are the prevailing causes of fungal infection of the skin, hair, and nails. These infections lead to a variety of clinical manifestations, such as tinea pedis, tinea corporis, tinea cruris, Majocchi's granuloma, tinea capitis, and tinea unguium (dermatophyte onychomycosis).

What is Majocchi's granuloma?

Dermatophyte infections are usually limited to the epidermis. Majocchi's granuloma is an uncommon condition in which the dermatophyte invades the dermis or subcutaneous tissue.

What is important additional management for tinea capitis?

Household members of an individual diagnosed with tinea capitis should be physically examined for signs of tinea capitis and should be treated simultaneously if tinea capitis is detected. Asymptomatic carriers of dermatophytes may serve as reservoirs for recurrent infection. Because of this possibility, we suggest use of an antifungal shampoo by all household members for two to four weeks. Bedding and towels used by the infected individual should be washed. Furniture that is frequently in direct contact with the affected individual or pet should be washed, if possible.

How does Majocchi's granuloma present clinically?

In immunocompetent patients, the clinical findings are typically characterized by a localized area with erythematous, perifollicular papules or small nodules.

What is the etiology of tinea capitis?

In the United States and the United Kingdom, T. tonsurans has replaced M. canis as the most common causative organism.

What differential diagnoses should be considered when evaluating a patient for tinea pedis?

Interdigital tinea pedis •Erythrasma •Interdigital Candida infection (erosio interdigitalis blastomycetica) Hyperkeratotic (moccasin-type) tinea pedis •Atopic dermatitis •Chronic contact dermatitis •Chronic palmoplantar (dyshidrotic) eczema •Palmoplantar psoriasis •Pitted keratolysis •Juvenile plantar dermatosis •Keratolysis exfoliativa •Keratodermas Vesiculobullous (inflammatory) tinea pedis •Acute palmoplantar (dyshidrotic) eczema •Acute contact dermatitis •Palmoplantar pustulosis •Scabies

How does tinea pedis manifest clinically?

Interdigital tinea pedis - Interdigital tinea pedis manifests as pruritic, erythematous erosions or scales between the toes, especially in the third and fourth digital interspaces. Associated interdigital fissures may cause pain. Hyperkeratotic (moccasin-type) tinea pedis - Hyperkeratotic tinea pedis is characterized by a diffuse hyperkeratotic eruption involving the soles and medial and lateral surfaces of the feet, resembling a "moccasin" distribution. There is a variable degree of underlying erythema. Vesiculobullous (inflammatory) tinea pedis - Vesiculobullous tinea pedis is characterized by a pruritic, sometimes painful, vesicular or bullous eruption with underlying erythema. The medial foot is often affected.

What differential diagnoses should be considered when evaluating a patient for tinea cruris?

Other common skin disorders that may present with erythematous patches or plaques in the inguinal region include inverse psoriasis, erythrasma, seborrheic dermatitis, and candidal intertrigo.

How is Majocchi's granuloma diagnosed?

Presumptive diagnosis is made based on the patient's history and clinical findings and is confirmed with a skin biopsy exhibiting fungal forms in the dermis.

What differential diagnoses should be considered when evaluating a patient for tinea capitis?

Psoriasis Alopecia areata Seborrheic dermatitis Bacterial folliculitis Folliculitis decalvans Dissecting cellulitis

What is the etiology of tinea corporis?

T. rubrum is the most common cause of tinea corporis. Other notable causes include Trichophyton tonsurans, Microsporum canis, T. interdigitale (formerly T. mentagrophytes), Microsporum gypseum, Trichophyton violaceum, and Microsporum audouinii.

What is the etiology of Majocchi's granuloma?

T. rubrum is the most frequent etiologic agent, although other dermatophytes have been implicated. Majocchi's granuloma may be precipitated by trauma to the skin or occlusion of hair follicles, leading to the disruption of hair follicles and passage of the dermatophyte into the dermis. Shaving the legs can be an inciting factor in women.

How is tinea pedis diagnosed?

The diagnosis is confirmed with the detection of segmented hyphae in skin scrapings from an affected area with a potassium hydroxide (KOH) preparation.

What is the etiology of tinea cruris?

The most common cause is T. rubrum. Other frequent causes include E. floccosum and T. interdigitale (formerly T. mentagrophytes). Tinea cruris is far more common in men than women. Often, infection results from the spread of the dermatophyte infection from concomitant tinea pedis. Predisposing factors include copious sweating, obesity, diabetes, and immunodeficiency.

How does tinea capitis present clinically?

The most common clinical manifestations of tinea capitis are the development of scaly patches with alopecia and patches of alopecia with visible black dots. Scaly patches with alopecia - Single or multiple scaly patches with hair loss are a common presentation of ectothrix infections (eg, M. canis). Individual patches are often a few centimeters to several centimeters in diameter. The patches enlarge centrifugally over the course of weeks to months. Erythema may be present. Patches of alopecia with black dots - Endothrix infections may present with manifestations often referred to as "black dot tinea capitis." Multiple black dots, which represent the distal ends of hairs that have broken at the surface of the scalp, are present at follicular orifices within areas of alopecia. The broken hairs are a result of weakening of the hair shaft secondary to the endothrix infection. The alopecic areas may be single or multiple and typically range from a few centimeters to several centimeters in diameter.

What is the prognosis of tinea capitis?

The prognosis of tinea capitis is excellent, with complete clearance occurring in most patients after a course of treatment. Complete hair regrowth occurs in most children with hair loss. Clinical follow-up to assess for clinical clearance should be performed at the end of therapy to assess for clinical cure.

What is tinea barbae?

Tinea barbae is a dermatophyte infection involving beard hair in adolescent and adult men. Oral antifungal therapy is necessary.

What is the epidemiology of tinea captitis?

Tinea capitis is a common disorder. Children, particularly prepubertal children, are most likely to develop tinea capitis. Some studies have identified higher prevalences in male children than in female children. Tinea capitis occurs worldwide with prevalences that vary geographically and demographically. Studies in the United States have revealed that tinea capitis is most common in African-American children.

How is tinea capitis acquired/transmitted?

Tinea capitis is acquired through contact of the scalp with the causative dermatophyte. Acquisition of the fungus may result from direct contact with an infected individual or animal or from contact with a contaminated object (eg, comb, brush, or hat). Contact with asymptomatic carriers of causative organisms is an additional mode of transmission that may play an important role in recurrences of tinea capitis and tinea corporis.

How is tinea captitis diagnosed?

Tinea capitis often can be diagnosed based upon the physical examination if there are alopecic patches with scaling or black dots consistent with tinea capitis. A potassium hydroxide (KOH) preparation or fungal culture should be performed to confirm tinea capitis if the diagnosis is in question.

What is tinea capitis?

Tinea capitis, dermatophyte infection of scalp hair, usually occurs in small children. Oral antifungal therapy is the treatment of choice.

What are the major clinical subtypes of dermatophyte infections?

Tinea corporis - Infection of body surfaces other than the feet, groin, face, scalp hair, or beard hair. Tinea pedis - Infection of the foot. Tinea cruris - Infection of the groin. Tinea capitis - Infection of scalp hair. Tinea unguium (dermatophyte onychomycosis) - Infection of the nail. Additional terms used to describe less common presentations are tinea faciei (infection of the face), tinea manuum (infection of the hand), and tinea barbae (infection of beard hair).

What differential diagnoses should be considered when evaluating a patient for tinea corporis?

Tinea corporis may be confused with other annular skin eruptions, especially subacute cutaneous lupus erythematosus (SCLE), granuloma annulare, and erythema annulare centrifugum.

How does tinea corporis present clinically?

Tinea corporis often begins as a pruritic, circular or oval, erythematous, scaling patch or plaque that spreads centrifugally. Central clearing follows, while an active, advancing, raised border remains. The result is an annular (ring-shaped) plaque from which the disease derives its common name (ringworm).

How is tinea corporis treated?

Tinea corporis usually responds well to topical antifungal drugs, such as azoles, allylamines, butenafine, ciclopirox, and tolnaftate. For children: -Terbinafine tablets -Terbinafine granules -Itraconazole -Fluconazole -Griseofulvin

How does tinea cruris present clinically?

Tinea cruris often begins with an erythematous patch on the proximal medial thigh. The infection spreads centrifugally, with partial central clearing and a slightly elevated, erythematous, sharply demarcated border that may have tiny vesicles. Infection may spread to the perineum and perianal areas, into the gluteal cleft, or onto the buttocks. In males, the scrotum is typically spared.

What is tinea faciei?

Tinea faciei is a dermatophyte infection of facial skin devoid of terminal hairs. The eruption may begin as small, scaly papules that evolve to form an annular plaque. Tinea faciei is managed similarly to tinea corporis.

What is tinea manuum?

Tinea manuum is dermatophyte infection of the hand. Patients present with a hyperkeratotic eruption on the palm or annular plaques similar to tinea corporis on the dorsal hand. Tinea manuum commonly occurs in association with tinea pedis and is often unilateral. This clinical presentation is often referred to "two-feet, one hand syndrome." The approach to treatment is similar to tinea pedis.

What is tinea pedis?

Tinea pedis (also known as athlete's foot) is the most common dermatophyte infection. Interdigital tinea pedis is most common. Tinea pedis frequently is accompanied by tinea unguium, tinea cruris, or tinea manuum.

What is the etiology of tinea pedis?

Tinea pedis usually occurs in adults and adolescents (particularly young men) and is rare prior to puberty. Common causes are Trichophyton rubrum, Trichophyton interdigitale (formerly Trichophyton mentagrophytes), and Epidermophyton floccosum. Infection is usually acquired by means of direct contact with the causative organism, as may occur by walking barefoot in locker rooms or swimming pool facilities.

How is tinea pedis treated?

Topical antifungal therapy is the treatment of choice for most patients. Systemic antifungal agents are primarily reserved for patients who fail topical therapy. Topical drugs effective for tinea pedis include azoles, allylamines, butenafine, ciclopirox, tolnaftate, and amorolfine. Typical treatment regimens for adults include: ●Terbinafine: 250 mg per day for two weeks ●Itraconazole: 200 mg twice daily for one week ●Fluconazole: 150 mg once weekly for two to six weeks

How is tinea cruris treated?

Treatment is similar to tinea corporis. Topical therapy with antifungal agents such as azoles, allylamines, butenafine, ciclopirox, and tolnaftate is effective. Recurrence of tinea cruris is common. Concomitant tinea pedis should be treated to reduce risk for recurrence.


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