AUTHOR AND EDITOR INFORMATION

Section 1 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

INTRODUCTION

Section 2 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Background

Tinea corporis is a superficial dermatophyte infection characterized by either inflammatory or noninflammatory lesions on the glabrous skin (ie, skin regions except the scalp, groin, palms, and soles). Three anamorphic (asexual or imperfect) genera cause dermatophytoses: Trichophyton, Microsporum, and Epidermophyton. Dermatophytes may infect humans (anthropophilic), infect nonhuman mammals (zoophilic), or reside primarily in the soil (geophilic).

Pathophysiology

Dermatophytes preferentially inhabit the nonliving, cornified layers of the skin, hair, and nail, which is attractive for its warm, moist environment conducive to fungal proliferation. Fungi may release keratinases and other enzymes to invade deeper into the stratum corneum, although typically the depth of infection is limited to the epidermis and, at times, its appendages. They generally do not invade deeply, owing to nonspecific host defense mechanisms that can include the activation of serum inhibitory factor, complement, and polymorphonuclear leukocytes.

Following the incubation period of 1-3 weeks, dermatophytes invade peripherally in a centrifugal pattern. In response to the infection, the active border has an increased epidermal cell proliferation with resultant scaling. This creates a partial defense by way of shedding the infected skin and leaving new, healthy skin central to the advancing lesion. Elimination of dermatophytes is achieved by cell-mediated immunity.

Trichophyton rubrum is a common dermatophyte and, because of its cell wall, is resistant to eradication. This protective barrier contains mannan, which may inhibit cell-mediated immunity, hinder the proliferation of keratinocytes, and enhance the organism's resistance to the skin's natural defenses.

Frequency

International

Tinea corporis is a common infection more often seen in typically hot, humid climates. T rubrum is the most common infectious agent in the world and is the source of 47% of tinea corporis cases. Trichophyton tonsurans is the most common dermatophyte to cause tinea capitis, and people with an anthropophilic tinea capitis infection are more likely to develop associated tinea corporis. Therefore, the prevalence of tinea corporis caused by T tonsurans is increasing. Microsporum canis is the third most common causative organism and associated with 14% of tinea corporis infections.

Mortality/Morbidity

Dermatophyte infections do not result in significant mortality, but they can greatly affect quality of life.

Sex

Tinea corporis occurs in both men and women. Women of childbearing age are more likely to develop tinea corporis as a result of their greater frequency of contact with infected children.

Age

Tinea corporis affects persons of all age groups, but prevalence is highest in preadolescents. Tinea corporis acquired from animals is more common in children. Tinea corporis secondary to tinea capitis typically occurs in children because tinea capitis is more common in this population.

CLINICAL

Section 3 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

History

Symptoms, contact history, recent travel, and international residence are relevant clues in the history of a person with tinea corporis.

• Infected patients may have variable symptoms.
• • Patients can be asymptomatic.
  • A pruritic, annular plaque is characteristic of a symptomatic infection.
  • HIV-positive or immunocompromised patients may develop severe pruritus or pain.

• Tinea corporis may result from contact with infected humans, animals, or inanimate objects. The history may include occupational (eg, farm worker, zookeeper, laboratory worker, veterinarian), environmental (eg, gardening, contact with animals), or recreational (eg, contact sports, contact with sports facilities) exposure.
• A few clinical variants are described, with distinct presentations.
• • Majocchi granuloma, typically caused by T rubrum, is a fungal infection in hair, hair follicles, and, often, the surrounding dermis, with an associated granulomatous reaction. Majocchi granuloma often occurs in females who shave their legs.
  • Tinea corporis gladiatorum is a dermatophyte infection spread by skin-to-skin contact between wrestlers.
  • Tinea imbricata is a form of tinea corporis found mainly in Southeast Asia, the South Pacific, Central America, and South America. It is caused by Trichophyton concentricum.

Physical

• Tinea corporis can manifest in a variety of ways.
• • Typically, the lesion begins as an erythematous, scaly plaque that may rapidly worsen and enlarge.
  • Following central resolution, the lesion may become annular in shape.
  • Scale, crust, vesicles, and papules often develop, especially in the advancing border.
  • Infections due to zoophilic or geophilic dermatophytes may produce a more intense inflammatory response than those caused by anthropophilic microbes.
  • Rarely, HIV-positive or immunocompromised patients can present with deep abscesses or dissemination.

• Majocchi granuloma manifests as perifollicular, granulomatous nodules typically in a distinct location, which is the lower two thirds of the leg in females.
• Tinea corporis gladiatorum often manifests on the head, neck, and arms, which is a distribution consistent with the areas of skin-to-skin contact in wrestling.
• Tinea imbricata is recognized clinically by its distinct scaly plaques arranged in concentric rings.

Causes

• Tinea corporis can be caused by a variety of dermatophytes, although prevalence and patient history are very helpful in identifying the most likely organism.
• • Internationally, the most common cause is T rubrum.
  • T tonsurans, Trichophyton mentagrophytes, and M canis are also known to produce infection.
  • Tinea imbricata is caused by T concentricum.

• Dermatophytoses may be acquired from different sources, such as people, animals, or soil.
• • Infected humans are the most common source of tinea corporis in the United States.
  • Contact with contaminated household pets, farm animals, and fomites (eg, hairbrushes, towels) can spread infection.

• Because fungal arthroconidia can survive in the environment, recurrent outbreaks may occur.

DIFFERENTIALS

Section 4 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

WORKUP

Section 5 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Lab Studies

• A potassium hydroxide (KOH) examination of skin scrapings may be diagnostic.
• • A KOH test is a microscopic preparation to visualize fungal elements removed from the skin's stratum corneum.
  • The sample should be taken from the active border of a lesion because this region provides the highest yield of fungal elements. A KOH preparation from a vesicular lesion should be made from the roof of the vesicle.
  • The KOH helps dissolve the keratin and leaves fungal elements intact, revealing numerous septate, branching hyphae amongst epithelial cells.
  • A counterstain, such as chlorazol black E or Parker blue-black ink, may help visualize hyphae under the microscope.

• A fungal culture is often used as an adjunct to KOH for diagnosis. Fungal culture is more specific than KOH for detecting a dermatophyte infection; therefore, if the clinical suspicion is high yet the KOH result is negative, a fungal culture should be obtained.
• A few culture mediums are available for dermatophyte growth.
• • Sabouraud agar containing neopeptone or polypeptone agar and glucose is often used for fungal culture. However, it does not contain antibiotics and may allow overgrowth of fungal and bacterial contaminants.
  • Mycosel, a commonly used agar, is similar to Sabouraud agar but has antibiotics.
  • Commonly, dermatophyte test medium (DTM) is used. It contains antibacterial (ie, gentamicin, chlortetracycline) and antifungal (ie, cycloheximide) solutions in a nutrient agar base. This combination isolates dermatophytes while suppressing other fungal and bacterial species that may contaminate the culture.

• Following culture inoculation, potential fungal growth is monitored for 2 weeks.
• Positive culture results vary depending on the medium used.
• • DTM contains phenol red solution, which causes a color change from straw-yellow to bright-red under alkaline conditions, indicating a positive dermatophyte culture result. However, the color makes identification of culture morphology (particularly pigmentation) difficult.
  • Sabouraud or Mycosel agar should be used to assess gross and microscopic colony characteristics.

Histologic Findings

A skin biopsy with a hematoxylin and eosin staining of tinea corporis demonstrates spongiosis, parakeratosis, and a superficial inflammatory infiltrate. Neutrophils may be seen in the stratum corneum, which is a significant diagnostic clue. On occasion, septate branching hyphae are seen in the stratum corneum with hematoxylin and eosin stain, but special fungal stains (eg, periodic acid-Schiff, Gomori methenamine silver) may be required.

TREATMENT

Section 6 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Medical Care

• Topical therapy is recommended for a localized infection because dermatophytes rarely invade living tissues. Topical therapy should be applied to the lesion and at least 2 cm beyond this area once or twice a day for at least 2 weeks, depending on which agent is used. Topical azoles and allylamines show high rates of clinical efficacy. These agents inhibit the synthesis of ergosterol, a major fungal cell membrane sterol.
• • The topical azoles (eg, econazole, ketoconazole, clotrimazole, miconazole, oxiconazole, sulconazole, sertaconazole) inhibit the enzyme lanosterol 14-alpha-demethylase, a cytochrome P-450–dependent enzyme that converts lanosterol to ergosterol. Inhibition of this enzyme results in unstable fungal cell membranes and causes membrane leakage. The weakened dermatophyte is unable to reproduce and is slowly killed by fungistatic action.

  • Allylamines (eg, naftifine, terbinafine) and the related benzylamine butenafine inhibit squalene epoxidase, which converts squalene to ergosterol. Inhibition of this enzyme causes squalene, a substance toxic to fungal cells, to accumulate intracellularly and leads to rapid cell death. Allylamines bind effectively to the stratum corneum because of their lipophilic nature. They also penetrate deeply into hair follicles.

  • Ciclopirox olamine is a topical fungicidal agent. It causes membrane instability by accumulating inside fungal cells and interfering with amino acid transport across the fungal cell membrane.

  • A low-to-medium potency topical corticosteroid can be added to the topical antifungal regimen to improve symptoms. The steroid can provide rapid relief from the inflammatory component of the infection, but the steroid should only be applied for the first few days of treatment.

• Systemic therapy may be indicated for tinea corporis that is extensive, involves immunocompromised patients, or is refractory to topical therapy. Use of oral agents requires attention to potential drug interactions and monitoring for adverse effects.
• • The mechanism of action of oral micronized griseofulvin against dermatophytes is disruption of the microtubule mitotic spindle formation in metaphase, causing arrest of fungal cell mitosis. A dose of 10 mg/kg/d for 4 weeks is effective. In addition, griseofulvin induces the cytochrome P-450 enzyme system and can increase the metabolism of CYP-450 dependent drugs.

  • Systemic azoles (eg, fluconazole, itraconazole, ketoconazole) function similar to the topical agents, causing cell membrane destruction. Oral ketoconazole at 3-4 mg/kg/d may be given; however, this agent has an associated risk of hepatitis in less than 1 in 10,000 cases and is now seldom used orally for dermatophyte infections. Fluconazole at 50-100 mg/d or 150 mg once weekly for 2-4 weeks may be used, with good results. Oral itraconazole at 100 mg/d for 2 weeks shows high efficacy. With an increased dose of 200 mg/d, the treatment duration may be reduced to 1 week. However, the cytochrome P-450 activity of itraconazole allows for potential interactions with other commonly prescribed drugs.

  • Oral terbinafine may be used at a dosage of 250 mg/d for 2 weeks; the potential exists for cytochrome P-450, specifically CYP-2D6, drug interactions with this agent.
  • Systemic therapy is needed when the infection involves hair follicles, such as Majocchi granuloma. In this case, topical therapy may serve as adjunct treatment with the oral medication.
  • The preferred treatment for tinea imbricata is griseofulvin or terbinafine, although some resistance has developed to oral griseofulvin.

Surgical Care

Surgical treatment is usually not indicated except for the drainage of superficial vesicles, bullae, pustules, or deep abscesses.

MEDICATION

Section 7 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

The goals of pharmacotherapy are to reduce morbidity and to prevent complications. Topical antifungal agents are effective for treating most cases of tinea corporis. Systemic therapy may be indicated for tinea corporis that is extensive, involves immunocompromised patients, or is refractory to topical therapy.

Drug Category: Topical allylamines

Drug Name	Terbinafine 1% cream (Lamisil)
Description	Fungicidal activity; synthetic allylamine derivative that inhibits squalene epoxidase, a key enzyme in sterol biosynthesis of fungi, resulting in deficiency in ergosterol that causes fungal cell death. Use until symptoms significantly improve.
Adult Dose	Apply to affected area qd for 1-4 wk
Pediatric Dose	<12 years: Not established >12 years: Administer as in adults
Contraindications	Documented hypersensitivity
Interactions	None reported with topical use
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Discontinue use if chemical irritation develops

Drug Category: Topical pyridones

Drug Category: Topical benzylamines

Drug Category: Systemic azoles

Drug Name	Itraconazole (Sporanox)
Description	Fungistatic activity; synthetic triazole antifungal agent that inhibits fungal cell growth by inhibiting the cytochrome P-450–dependent synthesis of ergosterol, a vital component of fungal cell membranes.
Adult Dose	100 mg/d PO for 2 wk or 200 mg/d PO for 1 wk; not to exceed 400 mg/d; increase in 100-mg increments if no improvement (administer >200 mg/d in divided doses)
Pediatric Dose	Not established Suggested dose in children 3-16 years: 100 mg/d PO for 1 wk
Contraindications	Documented hypersensitivity
Interactions	Antacids may reduce absorption; edema may occur with coadministration of calcium channel blockers (eg, amlodipine, nifedipine); hypoglycemia may occur with sulfonylureas; may increase tacrolimus and cyclosporine plasma concentrations when high doses are used; rhabdomyolysis may occur with coadministration of HMG-CoA reductase inhibitors (ie, lovastatin, simvastatin); coadministration with cisapride can cause cardiac rhythm abnormalities and death; may increase digoxin levels; coadministration may increase plasma levels of midazolam or triazolam; phenytoin and rifampin may reduce levels (phenytoin metabolism may be altered)
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Caution in hepatic insufficiencies (rare cases of reversible idiosyncratic hepatitis reported); monitor hepatic enzyme test values in preexisting hepatic function abnormalities

Drug Name	Ketoconazole (Nizoral)
Description	Inhibits synthesis of ergosterol (main sterol of fungal cell membranes), causing cellular components to leak; results is cell death.
Adult Dose	200-400 mg PO qd
Pediatric Dose	3.3-6.6 m/kg PO qd for 4 wk, not to exceed 400 mg/dose
Contraindications	Documented hypersensitivity; fungal meningitis
Interactions	Isoniazid may decrease bioavailability; coadministration decreases effects of either rifampin or ketoconazole; may increase effect of anticoagulants; may increase toxicity of corticosteroids and cyclosporine (cyclosporine dosage can be adjusted); may decrease theophylline levels; decreases metabolism of repaglinide, thus increasing serum levels and effects
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	Hepatotoxicity may occur; may reversibly decrease corticosteroid serum levels (adverse effects avoided with dose of 200-400 mg/d); administer antacids, anticholinergics, or H2-blockers at least 2 h after taking ketoconazole

Drug Category: Systemic allylamines

Drug Category: Other systemic antifungals

Drug Category: Topical azoles

Drug Name	Ketoconazole 2% cream (Nizoral)
Description	Imidazole, broad-spectrum antifungal agent indicated for topical treatment of tinea corporis. Inhibits synthesis of ergosterol (main sterol of fungal cell membranes), causing cellular components to leak; result is cell death.
Adult Dose	Rub gently into affected area qd or bid for 2-4 wk
Pediatric Dose	Apply as in adults
Contraindications	Documented hypersensitivity; fungal meningitis
Interactions	None reported
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	If sensitivity or irritation develops, discontinue use; for external use only; avoid contact with eyes

Drug Name	Miconazole 2% cream or lotion (Monistat)
Description	Damages fungal cell-wall membrane by inhibiting biosynthesis of ergosterol. Membrane permeability is increased, causing nutrients to leak and resulting in fungal cell death. Lotion is preferred in intertriginous areas. If cream is used, apply sparingly to avoid maceration effects.
Adult Dose	Cream and lotion: Cover affected areas bid for 2-6 wk Powder: Spray or sprinkle liberally over affected area bid
Pediatric Dose	Apply as in adults
Contraindications	Documented hypersensitivity
Interactions	None reported for topical use
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	If sensitivity or irritation develops, discontinue use; for external use only; avoid contact with eyes

Drug Name	Oxiconazole 1% cream (Oxistat)
Description	Damages fungal cell wall membrane by inhibiting biosynthesis of ergosterol. Membrane permeability is increased, causing nutrients to leak, resulting in fungal cell death.
Adult Dose	Apply to affected area qid
Pediatric Dose	Administer as in adults
Contraindications	Documented hypersensitivity
Interactions	None reported
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	If sensitivity or chemical irritation occurs, discontinue use; external use only; avoid contact with the eyes

Drug Name	Sertaconazole 2% cream (Ertaczo)
Description	Topical imidazole antifungal active against T rubrum, T mentagrophytes, and Epidermophyton floccosum.
Adult Dose	Apply topically bid for 2-4 wk
Pediatric Dose	<12 years: Not established >12 years: Administer as in adults
Contraindications	Documented hypersensitivity
Interactions	None reported
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	For topical use only; may cause dermatitis, dry skin, burning sensation, pruritus, hyperpigmentation, desquamation, or skin tenderness

Drug Name	Sulconazole 1% cream or solution (Exelderm)
Description	Broad-spectrum antifungal agent that inhibits synthesis of ergosterol, causing cellular components to leak and resulting in fungal cell death.
Adult Dose	Apply topically to affected area qd for 2-4 wk
Pediatric Dose	<12 years: Not established >12 years: Administer as in adults
Contraindications	Documented hypersensitivity
Interactions	None reported
Pregnancy	C - Safety for use during pregnancy has not been established.
Precautions	If sensitivity or chemical irritation occurs, discontinue use; use only externally; avoid contact with the eyes

FOLLOW-UP

Section 8 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Further Outpatient Care

• Follow-up care should be determined per patient need, severity of infection, and response to treatment.

In/Out Patient Meds

• See Medication.

Deterrence/Prevention

• Imperative for preventing the spread of a dermatophyte infection is to discourage close contact between infected and noninfected individuals and to stop the sharing of fomites (eg, towels, hats, clothing).
• Because dermatophytes flourish in moist environments, patients should be advised to wear loose-fitting clothing made of cotton or synthetic materials.

Complications

• The infection may recur if therapy does not result in complete eradication of the organism, such as when patients stop applying topical therapy too soon or if the organism is resistant to the antifungal agent used.
• Reinfection may occur if a reservoir, such as an infected nail or hair follicle, is present. Many, if not most, adult patients with tinea corporis also have tinea pedis and unguium, which should be treated.

Prognosis

• For localized tinea corporis, the prognosis is excellent, with cure rates of 70-100% after treatment with topical azoles or allylamines or short-term or pulse systemic antifungals.

Patient Education

• For excellent patient education resources, visit eMedicine's Skin, Hair, and Nails Center. Also, see eMedicine's patient education article Ringworm on Body.

MULTIMEDIA

Section 9 of 10  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

Media file 1:  Annular plaque.
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Media type:  Photo

Media file 2:  Large, erythematous, scaly plaque.
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Media type:  Photo

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Multimedia
• References

• Adams BB. Tinea corporis gladiatorum. J Am Acad Dermatol. Aug 2002;47(2):286-90. [Medline].
• Aly R. Ecology and epidemiology of dermatophyte infections. J Am Acad Dermatol. Sep 1994;31(3 Pt 2):S21-5. [Medline].
• Dahl MV. Dermatophytosis and the immune response. J Am Acad Dermatol. Sep 1994;31(3 Pt 2):S34-41. [Medline].
• Drake LA, Dinehart SM, Farmer ER, et al. Guidelines of care for superficial mycotic infections of the skin: tinea corporis, tinea cruris, tinea faciei, tinea manuum, and tinea pedis. Guidelines/Outcomes Committee. American Academy of Dermatology. J Am Acad Dermatol. Feb 1996;34(2 Pt 1):282-6. [Medline].
• Foster KW, Ghannoum MA, Elewski BE. Epidemiologic surveillance of cutaneous fungal infection in the United States from 1999 to 2002. J Am Acad Dermatol. May 2004;50(5):748-52. [Medline].
• Gupta AK, Einarson TR, Summerbell RC, Shear NH. An overview of topical antifungal therapy in dermatomycoses. A North American perspective. Drugs. May 1998;55(5):645-74. [Medline].
• Jones HE. Immune response and host resistance of humans to dermatophyte infection. J Am Acad Dermatol. 1998;28 (5 Pt 1):S12-S18.
• Lesher JL. Therapeutic agents for dermatologic fungal diseases. In: Elewski BE, ed. Cutaneous Fungal Infections. Malden: Blackwell Science; 1998:321-46.
• Lesher JL Jr. Oral therapy of common superficial fungal infections of the skin. J Am Acad Dermatol. Jun 1999;40(6 Pt 2):S31-4. [Medline].
• Leyden J. Pharmacokinetics and pharmacology of terbinafine and itraconazole. J Am Acad Dermatol. May 1998;38(5 Pt 3):S42-7. [Medline].
• Macura AB. Dermatophyte infections. Int J Dermatol. May 1993;32(5):313-23. [Medline].
• Pierard GE, Arrese JE, Pierard-Franchimont C. Treatment and prophylaxis of tinea infections. Drugs. Aug 1996;52(2):209-24. [Medline].
• Rezabek GH, Friedman AD. Superficial fungal infections of the skin. Diagnosis and current treatment recommendations. Drugs. May 1992;43(5):674-82. [Medline].
• Weinstein A, Berman B. Topical treatment of common superficial tinea infections. Am Fam Physician. May 15 2002;65(10):2095-102. [Medline].
• Wingfield AB, Fernandez-Obregon AC, Wignall FS, Greer DL. Treatment of tinea imbricata: a randomized clinical trial using griseofulvin, terbinafine, itraconazole and fluconazole. Br J Dermatol. Jan 2004;150(1):119-26. [Medline].

Article Last Updated: Jun 29, 2006