Tinea infections

Cellulitis and erysipelas are bacterial infections of the skin. Although separate entities, there is some clinical difficulty in distinguishing the two. 0 Cellulitis is a bacterial infection of the dermis and subcutaneous tissue, whereas erysipelas is a more superficial infection of the upper dermis and superficial lymphatics. Although both can occur on any part of the body, about 90% of infections involve the leg.8,9 Another 7.5% of cases involve the arm or face. Erysipelas is most common in the young and the elderly. Typically, both infections develop after a break in skin integrity, resulting from trauma, surgery, ulceration, burns, tinea infection, or other skin disorder. 

Tinea infections are superficial fungal infections in which the pathogen remains within the keratinous layers of the skin or nails. Typically these infections are named for the affected body part, such as tinea pedis (feet), tinea cruris (groin), and tinea corporis (body). Tinea infections are commonly referred to as ringworm due to the characteristic circular lesions. In actuality, tinea lesions can vary from rings to scales and single or multiple lesions. 

Tinea infections are second only to acne in frequency of reported skin disease.35 The common tinea infections are tinea pedis, tinea corporis, and tinea cruris. Tinea pedis, the most prevalent cutaneous fungal infection, afflicts more than 25 million people annually in the United States. 

Fungal skin infections are primarily caused by dermatophytes such as Trichophyton, Microsporum, and Epidermophyton. Trichophyton rubrum accounts for more than 75% of all cases in the United States.36 To a lesser extent, Candida and other fungal species cause skin infections. With tinea infections, the causative dermatophyte typically invades the stratum corneum without penetration into the living tissues, leading to a localized infection. 

Treatment is typically initiated based on symptoms, rather than on microscopic evaluation. Since several species can cause tinea infections, the choice of antifungal agent is not always clear. For infections accompanied by inflammation, combination therapy with a topical steroid can be considered. 

Unlabeled Uses Angiostrongyliasis, capillaria infestations, dracunculus infestations, pediculosis capitis, tinea infections... 

Nonprescription topical antifungal agent not effective in the treatment of deeper fungal infections of the skin, nor is it reliable in the treatment of fungal infections involving the scalp or nail beds Candida is resistant useful for patients desiring self-medication of mild tinea infections patients must be advised of limitations... 

Cyclopirox olamine is used in the treatment of tinea infections, dermal and vaginal candidiasis. 

Tolnaftate (Aftate, Tinactin) is available as a cream, solution, powder, or powder aerosol for application twice daily to infected areas. Recurrences following cessation of therapy are common, and infections of the palms, soles, and nails are usually unresponsive to tolnaftate alone. The powder or powder aerosol may be used chronically following initial treatment in patients susceptible to tinea infections. Tolnaftate is generally well tolerated and rarely causes irritation or allergic contact sensitization. 

Naftifine, tolnaftate, and butenafine are used primarily to treat local and superficial cases of tinea infection. These agents are found in several over-the-counter products that are administered topically to treat tinea infections such as tinea pedis and tinea cruris. 

Fungi that cause superficial skin infections are called dermatophytes. Common dermatomycoses, such as tinea infections, are often referred to as ringworm, which is a misnomer, since fungi rather than worms cause the disease. 

Antifungal spectrum The drug is principally fungistatic. It is effective only against the dermatophytes—Trichophyton. Microsporum. and Epidermophyton. It is used in the treatment of severe tinea infections that do not respond to other antifungal agents. 

Haloprogin, USP. 3-lodo-2-propynyl-2.4,5-trichloro-phenyl ether (Halotcx) crystallizes as white to pale yellow forms that are sparingly soluble in water and very soluble in ethanol. It is an ethereal derivative of a phenol. Haloprogin is used as a 1% cream for the treatment of superficial tinea infections. Formulations of haloprogin should be protected... 

Econazole is used as a 1% cream for the topical treatment of local tinea infections and cutaneous candidiasis. 

Sulconazole Nitrate, U5P. l-[2.4-Dichlon>- y>-chlor-ohenzyl)thio phenethyl imidazole mononitrate (Exelderm) is the white crystalline nitric acid salt of. sulconazole. It is sparingly. soluble in water but soluble in ethanol. The salt is used in a solution and a cream in 1% concentration for the treatment of local tinea infections, such as jock itch, athlete s foot, and ringworm. 

Miconazole nitrute is supplied in a variety of dosage fonns (cream, lotion, powder, and spray) for the treatment of tinea infections and cuiiineous candidiasis. Vaginal creams and. suppositories are also available for the treatment of vaginal candidiasis. A conceiiiraiion of 2% of the salt is u.sed in moii topical preparations. 

Ketoconazole is alsn used topically in a 2% concentratinn in a cream and in a shampoo for the management of cuta-Ecixis candidiasis and tinea infections. 

In 1997, garlic was the most widely used natural supplement in US households. Garlic was shown to be used more than twice as much as any other natural supplement (5). Garlic is promoted to lower cholesterol and blood pressure, delay the progression of atherosclerosis, prevent heart disease, improve circulation, prevent cancer, and is used topically for tinea infections (3,4). 

Ketoconazole is not available on the NHS for tinea infections, but tubes of maximum 15 g ketoconazole 2% can be sold over the counter and as such could be supplied by registered podiatrists. See Chapter 14 for more information on how the law applies to sale and supply of medicines by podiatrists. 

Another useful addition to the antifungal armamentarium is the hydroxypyridone ciclopirox. Its broad fungicidal activity includes all of the dermatophytes, yeasts, and M. furfur (versicolor). The neutral cream is therefore indicated for the various tinea infections (see Table 7-7) and superficial candidiasis. The mechanism of ciclopirox has not been fully determined, but appears to involve inhibition of uptake from the medium of precursors by the pathogen for the biosynthesis of the biopolymers needed for survival. 

Naftifine (Fig. 40.8) was the first allyl amine to be discovered and marketed (34). It is subject to extensive first-pass metabolism to be orally active and, consequently, is only available in topical preparations (Table 40.1). The widest use of naftifine is against various tinea infections of the skin. 

Dermatophyte fungi are moulds that spedfically infect the keratinised layers of the skin by virtue of their ability to degrade keratin. Three genera, Epidermophyton, Miao-sporum and Trichophyton, are responsible for causing ringworm or tinea infections (dermatophytosis). Griseofulvin is used exclusively for the oral treatment of dermatophyte infections where topical therapies have failed or are inappropriate. 

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