Tinea cruris, also known as crotch itch, crotch rot, Dhobi itch, eczema marginatum, gym itch, jock itch, jock rot, scrot rot and ringworm of the groin is a dermatophyte fungal infection of the groin region in any sex, though more often seen in males.
Signs and symptoms
As the common name for this condition implies, it causes itching or a burning sensation in the groin area, thigh skin folds or anus. It may involve the inner thighs and genital areas, as well as extending back to the perineum and perianal areas.
Tinea is often painful or itchy, but not in every case. There are visual clues to help identify a fungal infection. These include:
- Inflammation of the groin, anal area and upper thigh - not including the genitals themselves
- slightly raised patch
- sharp borders
- expanding or spreading, with clearing in the center
- dry or scaly blisters (occasionally oozing or crusting)
- abnormally dark or light skin
- skin redness or inflammation
Fungal infections often spread out in a circle, leaving normal-looking skin in the middle. At the leading edge of the infection the skin is raised, red and scaly.
Affected areas may appear red, tan, or brown, with flaking, rippling, peeling or cracking skin.
The acute infection begins with an area in the groin fold about a half-inch across, usually on both sides. The area may enlarge, and other sores may develop. The rash has sharply defined borders that may blister and ooze.
Tinea cruris does have similar symptoms to Inverse psoriasis.
Causes
Opportunistic infections (infections that are caused by a diminished immune system) are frequent. Fungus from an athlete's foot infection can spread to the groin through clothing. Tight, restrictive clothing, such as jockstraps, traps heat and moisture, providing an ideal environment for the fungus.
The type of fungus involved is usually Trichophyton rubrum. Some other contributing fungi are Candida albicans, Trichophyton mentagrophytes and Epidermophyton floccosum.
Diagnosis
Tinea cruris is similar to, but different from Candidal intertrigo, which is an infection of the skin by Candida albicans. The latter is more specifically located between intertriginous folds of adjacent skin, which can be present in the groin or scrotum, and be indistinguishable from fungal infections caused by tinea. However, candidal infections tend to both appear and with treatment disappear more quickly. It may also affect the scrotum.
Prevention
Medical professionals recommend a preventative based approach of stopping fungus before it occurs. Prevention is preferable over a reactive treatment approach. The preventative based approach involves removing heat and moisture to the groin area.
- Dry off with a clean towel immediately after showering, swimming or perspiring.
- Shower after physical activities.
- Wear underwear with high air and moisture permeability fabric, such as linen (flax).
Treatment
Tinea cruris is best treated with topical antifungal medications of the allylamine or azole type. The evidence is best for terbinafine and naftifine but other agents may also work.
The benefits of the use of topical steroids in addition to an antifungal is unclear. There might be a greater cure rate but no guidelines currently recommend its addition. The effect of Whitfield's ointment is also unclear.
References
External links
- eMedicineHealth.com
- MayoClinic.com, jock itch.
- Jock Itch / Tinea Cruris Pictures (Hardin MD Super Site Samples)
- Genekeyes.com, how to Prevent Jock Itch with Rubbing Alcohol.