Jock itch, which is called Tinea cruris in medical terminology, is a fungal infection of the skin that could involve the groin including the upper inner thighs, pubic region and the area around the genitalia. In boys, the penis is not usually involved. Tinea refers to fungus, and cruris refers to the area of body, in this case the groin, that the fungus could infect. The group of fungi that cause jock itch are called the dermatophytes. These fungi have the ability to infect and survive only on the top or dead layer of skin, the hair and the nails. They cannot live on surfaces such as the mouth, vagina or the anus. The dermatophytes may also cause Tinea capitis (ringworm of the scalp), Tinea cruris (ringworm of the body), Tinea pedis (athlete’s foot) and Tinea unguium (fungal infection of the nails); there is some evidence that there may be a genetic susceptibility to dermatophyte infections.
Who is likely to develop jock itch?
Jock itch is almost exclusively a problem of adolescent and adult males. There are several factors that explain the prevalence for the male gender. Males tend to wear more occlusive clothing than women. Fungi are more likely to cause infection if the skin is moist from perspiration. Because of the male anatomy in the genital region, the scrotum may cause more occlusion as it contacts the inner upper thighs. As a result of this occlusion, there is increased likelihood of skin moistness and increased heat. Compared to females, males are more likely to be physically active and this may result in the groin becoming warm and moist for an extended period. It is felt also that males are more likely to have other sites of dermatophyte infection including athlete’s foot. These other sites may serve as reservoirs of fungi and help to spread the infection to other sites of the body. Adolescent males may take less of an interest in personal hygiene compared to adolescent females. And adolescent males may not be aware of the possibility that an infection of the feet may be spread to the groin by careless scratching. Many authorities feel that the feet are the likely source of the fungus when an individual develops a new case of jock itch.
Athletic equipment may also predispose males to jock itch. An athletic supporter, or jock strap, may increase perspiration around the upper inner thighs and also bring on chafing. Athletic cups, a piece of equipment used to prevent injury to the male genitals during collision sports, may also increase moisture in the region and prevent adequate ventilation.
There is a seasonal distribution to jock itch. It is well known that this type of fungal infection occurs more commonly during the summer months or in tropical or subtropical climates. Occlusion from wet bathing suits is also felt to be a risk factor. In the cold weather, wearing several layers of clothing can produce a warm and moist environment in the groin.
What are the symptoms of jock itch?
The rash associated with jock itch is usually on both upper inner thighs in the areas where the scrotum contacts the thigh. The rash is usually red or red brown, sometimes it is scaly, the shape is often like a half moon and it has a well-defined border. The rash is itchy and if there is some skin softening due to the fungal infection, it may be painful. There may be signs of a bacteria infection such as pussy areas if there is infection due to the patient scratching the area.
How is jock itch evaluated?
Some clinicians are able to diagnose jock itch on the basis of the patient’s symptoms and the clinical appearance. The fungi responsible for jock itch can be detected by a simple microscopic examination. Scrapings of the rash are placed on a glass slide, some potassium hydroxide solution is added, and the preparation is examined under a light microscope. Outlines of the fungus may appear under magnification, and this is good diagnostic evidence that the patient has jock itch. Although it is generally not necessary, skin scrapings from the rash can be placed onto a fungal culture medium. This is incubated in a laboratory and after one or two weeks, there may be evidence of dermatophyte growth.
How is jock itch treated?
The treatment is aimed at altering the environment to discourage the growth of fungi, discussion of proper hygiene, topical medication and treatment of any other fungal infections. Since the fungi thrive in a moist and warm environment, loose fitting, clean, cotton underwear is recommended. This should reduce moisture, promote evaporation and prevent chafing. A daily shower at a minimum, and showering after athletics is also recommended. The adolescent should be told not to scratch his feet then touch his groin. After showering, he should dry the groin first then continue with the remainder of the body.
There are a number of topical anti-fungal medications available. These include econazole, miconazole, clotrimazole, tolnaftate and haloprogin. Although the rash may begin to improve quickly, most experts recommend treatment for about twenty-one days. Usually the creams are used two times a day, morning and evening on the rash. The cream should be used on the rash and at least one inch beyond the borders of the rash. Oral anti-fungal medications are rarely used to treat jock itch.
It is important to treat all of the fungal skin infections at the same time. Since some individuals have jock itch and athlete’s foot concurrently, then measures to treat the athlete’s foot should occur as the patient is treating the jock itch.
How is jock itch prevented?
Adolescent males should take measures to increase the ventilation of the groin and reduce perspiration. Cotton non-occlusive underwear is helpful as is frequent showering. Be sure to wash your jock strap after each use. Attention to personal hygiene is important. Since adolescent females are rarely if ever afflicted with jock itch, it is unlikely to be transmitted sexually between male and female. However, direct groin contact between an infected male and an uninfected male could theoretically transmit jock itch to the uninfected male. Indirect transmission may also occur. For example, bed linens, towels and articles of clothing have been found to harbor fungi during epidemics, and the dermatophytes have been known to survive for long periods of time. The best advice then is for adolescents not to share unwashed towels, clothing-especially underwear, and not to share bed linens that have not been washed.
Related topics:
Athlete’s foot, athletic equipment, fungal infections, gay and transsexual adolescents, skin disorders
