Slang terms

Jock itch is also sometimes called crack fungus, crotch itch, ball cheese or crotch rot, dhobi itch (after Indian washermen).

Symptoms and signs

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.

Affected areas may appear red, tan, or brown, with flaking, peeling, or cracking skin.[1][2]

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 in no particular pattern. The rash appears as raised red plaques (platelike areas) and scaly patches with sharply defined borders that may blister and ooze.[3]

If the rash advances, it usually advances down the inner thigh. The advancing edge is redder and more raised than areas that have been infected longer. The advancing edge is usually scaly, and very easily distinguished or well demarcated.

The skin within the border turns a reddish-brown and loses much of its scale. The border may exhibit tiny pimples or even pustules, with central areas that are reddish and dry with small scales.[4][5]

If infected with candidal organisms, the rash tends to be redder and wetter. The skin of the penis may be involved, whereas other organisms spare the penis.

Causes

Opportunistic infections (infections that are caused by a diminished immune system) are frequent. Fungus from other parts of the body (commonly tinea pedis or 'athlete's foot') can contribute to jock itch. A warm, damp environment allowing the fungus to cultivate greatly contributes; especially with tight, sweaty or rubbing clothing such as jockstrap or tight undershorts.

The type of fungus that most commonly causes jock itch is called Trichophyton rubrum. Some other contributing fungi are Candida albicans, Trichophyton mentagrophytes and Epidermophyton floccosum.

Treatment

Jock itch is best treated with antifungal drugs applied topically. Traditionally creams containing clotrimazole or miconazole have been used, although newer agents such as butenafine are also used. These anti-fungal agents work by stopping the fungi from producing a substance called ergosterol, which is an essential component of fungal cell membranes. If ergosterol synthesis is completely or partially inhibited, the cell is no longer able to construct an intact cell membrane. This leads to death of the fungus.

If the skin inflammation causes discomfort and itching, glucocorticoid steroids may be combined with the anti-fungal drug to help prevent further irritation due to the patient scratching the area. Apart from the quicker relief of symptoms, this also helps minimise the risk of secondary bacterial infection caused by the scratching. However steroids, if used alone, for fungal infections may exacerbate the condition.

Preventing recurrence

There are practices that can help reduce the risk of recurrence. Bear in mind that fungus can be very resilient both on the body and on clothing. To eliminate it permanently may require diligence. A long term or serious fungal infection may inflame the skin and make it more prone to sweating, and hence more ideal for recurrence. Ibuprofen or other anti-inflammatory drugs may be used to reduce inflammation.

Dryness

Bathe or shower immediately after sweating. This is especially important after exercising, where there has been sweating and irritation from friction. Use a medicated powder such as tolnaftate to keep the groin area dry. A hair dryer (preferably one with a "cool" setting) can be very helpful too, especially if you use water instead of toilet paper, as is recommended to prevent skin damage.

Irritants

Several materials and activities can aggravate jock itch, such as:

• Scented or antibacterial soaps. (Consider hypoallergenic or acidic candida soaps)
• Sweating and friction, such as cycling or regularly shaving your hairs.
• Synthetic materials.
• Avoid applying talcum powder to the affected area as it has the tendency to perforate and irritate the damaged skin and thus worsening the itch.

Clothing

Clothing is especially important. If fungus resides on your clothing, and you are susceptible to it, the odds of recurrence are much higher.

It can help to:

• Wear loose underwear, such as boxer shorts.
• Sleep with a nightshirt or in the nude.
• Change underwear frequently, particularly if it gets sweaty.

There are ways to help keep clothing free of fungus.

• Wash exercise clothing between workouts.
• Wash underwear and bed-sheets in hot water.
• Be mindful of clothing storage. In particular, because of the ideal growing conditions for fungus, avoid storage:
  • of exercise clothing without washing it,
  • in damp or moist areas,
  • in dark places, and
  • with poor ventilation.

When putting on and taking off (under)shorts, the feet can transfer fungus to the crotch and vice versa.