Diagnostic Hallmarks

DistJibution: varies with the type of fungal infection

KOH preparations and fungal cultures

Clinical Presentation

The clinical appearance of these diseases depends to a very large extent on the location of the disease. KOH preparations and/ or culture is recommended for confirmation of a clinical diagnosis.

Tinea pedis usually begins with the development of a fissure in the web space between the fourth and fifth toes. Keratin buildup occurs on the edges of the fissures, and because of maceration, the keratin usually appears white and soggy. From there the infection can spread to the toenails and to the bottom of the feet. Fungal infection on the plantar aspect of the foot occurs as a red scaling plaque that curves a short way up the sides of the foot (moccasin distribution). Vesicles occasionally develop on the instep of the foot .

Tinea pedis is found in teenagers and adults; it rarely develops in children. Patients with mild disease are usually asymptomatic, but in some instances heat and sweating cause considerable itching. Resultant scratching converts the original papulosquamous process to that of an eczematous disease. When that occurs, the dorsal surface of the toes and that of the feet often become eczematized.

Tinea manum most often occurs as an asymptomatic, noninflammatory scaling condition on the palm of one hand. The disease is so subtle there is a tendency to dismiss the scaling as simply that of dry skin, unless the two palms are compared. In cases of long-standing duration, involvement of one or more fingernails may also be noted. When tinea manum is present, evidence of tinea pedis can also always be found. This distribution is pathognomonic of so-called "two feet-one hand" dermatophyte fungal infection.

Tinea cruris is characterized by the development of sharply marginated, red plaques on the upper inner thighs. Lesions first appear close to the inguinal-scrotal crease and slowly advance down the inner sides of the thighs. As advancement occurs, healing of the previously involved proximal portion of the thigh is seen. This results in the appearance of an advancing, thin, semicircular line ("ringworm") on the inner thighs. A small amount of scale forms at the active border, but it is often obscured because of the moisture retained in the groin. The penis and scrotum are not involved, but extension onto the buttocks may be seen. Tinea cruris does not develop prior to puberty. Men are much more commonly infected than women. The lesions are usually asymptomatic, hut retention of heat and sweating sometimes cause considerable itching. Resultant scratching converts the papulosquamous appearance to that of an eczematous process.

Tinea corporis occurs in two forms: zoophilic infections acquired from animals and anthropophilic infections acquired Crom person-to-person contact or from fomites. Zoophilic infections appear as circular, bright red, sharply marginated, scaling plaques. The scale may be white or somewhat yellow. Often, only a single plaque is present, but occasionally three or four may be seen. The size of the plaques varies from 2 to 5 cm in diameter. The plaques are often solid, but annular forms are also seen. Those infections that are acquired from pets or farm animals occur in both children and adults.

Anthropophilic infections, on the other hand, are found only in adults. They occur as larger, annular lesions with gyrate or serpiginous borders. Although the lesions are annular, incomplete forms may be present such that only fragments of the circles are recognized. The erythematous, thin border of the lesions is a dull red, and the amount of scale present is highly variable. Small erythematous papules are regularly found within the larger annular lesion.

These generally represent fungal infection of the hair follicles. Lesions are most commonly found on the buttocks and around the waist, but involvement of the face or dorsal surface of the hands also occurs. Most lesions of tinea corporis are asymptomatic, but excoriations may be present, especially in areas where sweat is retained.

Author's Bio: 

Do you wish to know more about makeup & beauty or teen skin care Then have a look at authors site on which you will also find medicinal herbs