Jock Itch

Jock itch or intertrigo of the groin is commonly caused by a fungal infection.

Jock itch is the popular name given to an itchy rash in the groin that commonly involves the inner thighs and adjacent skin, including the scrotum in males. The medical name for rash in the creases of overlapping skin is "intertrigo." Jock itch is associated with sweating, friction/abrasion, occlusive clothing, and the direct rubbing of skin on skin. The rash may affect not only the groin, but it can involve any areas of skin that overlap, including around the anus and in the skin folds of obese individuals. Jock itch affects men and occasionally women worldwide.

Major risk factors include the following:

• Heat
• Humidity
• Tight clothing
• Damp skin folds that may occur with obesity or excessive sweating

Although several microorganisms have been identified as causing the rash, many cases are noninfectious and are induced by environmental and physical factors that irritate the skin. Other skin diseases may mimic jock itch. They include

• psoriasis,
• allergic contact dermatitis,
• hidradenitis suppurativa, and
• dandruff (seborrheic dermatitis).

Although the term jock itch implies some sort of relationship with athletics, this is not necessarily true. Jock itch is particularly related to infections from microorganisms and environmental factors such as humidity and friction, which can irritate the skin. Jock itch is more common in men than in women simply because the presence of male genitalia leads to increased friction and humidity. Women are actually predisposed to develop a similar condition underneath their breasts. Jock itch is most often caused simply by noninfected skin affected by friction, humidity, and heat. However, it is not uncommon for microorganisms like fungi and bacteria to simultaneously infect the skin.

• People taking broad-spectrum antibiotics, those with weakened immune systems, or those who have diabetes are at risk to develop the rash.
• Occasionally, bacteria can cause jock itch. Bacterial jock itch can be easily diagnosed because the affected skin glows a coral red color when illuminated by a black light.
• Wearing tight clothes or athletic supporters can predispose one to infection or aggravate the problem further. Jock itch can be prevented by applying large amounts of lubricant, like petroleum jelly, to areas likely to be affected.
• Intimate contact or contact with objects that harbor fungus can contaminate the groin skin. The fungus is spread by contact with the spores, which may survive on dead skin cells or objects for a long time.
• If you have fungal infection, such as athlete's foot, the same organism may cause a rash in your groin.
  • Infections caused by Candida albicans (a yeast) can produce pustules and involve the tip of the uncircumcised penis. This infection is seen more often in people with diabetes.
  • Fungal molds like the Epidermophyton floccosum and Trichophytin species are occasionally responsible for the epidemic infections in dormitories, barracks, and similar situations in which people live close together and in which towels, sheets, blankets, and other items may harbor a fungus for years.

• The condition begins with an itchy area of redness in a skin fold. The area may enlarge in no particular pattern. The rash appears as raised red plaques (platelike areas) with sharp borders. The border may exhibit tiny pimples or even pustules with central areas that are reddish and dry with small scales. If you become infected with yeast organisms, the rash tends to be redder and moist. The skin of the tip of the penis may be involved, whereas other organisms spare the male genitalia. Women who also have vaginal yeast infection experience vaginal itching and white, thick, cottage cheese-like discharge.
• The rash becomes more irritating with time and may, in severe cases, feature breakdown of the skin that is quite uncomfortable.

When to call the doctor

• The appearance of an itchy red rash in your groin or genital area should prompt a visit to your doctor.
• Once you have been diagnosed, go back to the doctor if the rash does any of these things:
  • Spreads or changes appearance
  • Becomes increasingly uncomfortable
  • Develops lumps or swelling of the affected areas
  • Does not improve after two weeks of treatment
  • Does not go away completely or comes back frequently despite proper prevention

When to go to the hospital

Go to a hospital's emergency department if you develop any of the following symptoms beyond the rash:

• Fever
• Weakness
• Vomiting
• Rapid spread of the rash
• Swollen glands
• Lumps in the groin
• Drainage of pus
• Open sores or ulcers
• Boils
• Rash that involves your penis or vaginal area
• Difficulty urinating
• Rash that spreads to your trunk

The doctor will take your medical history and give you a physical examination. In most cases, the doctor will begin treatment on a trial basis. If the diagnosis remains in question or the rash does not respond to the initial treatment, the doctor will perform laboratory tests to aid in the diagnosis.

Your history should include the following:

• Any medical conditions you may have
• Questions regarding all current symptoms, including these
  • Excessive thirst
  • Excessive urination
  • Fever
  • When the rash began
  • Infections or rashes you had before
• Current and past medication history, including any treatments you tried at home
• Social history includes the following:
  • Sexual history
  • HIV status
  • Gym or sports activity
  • Use of communal pool or whirlpool
  • Pets
• Travel history, including any recent vacations, camping activities, and military reserve training
• A thorough physical examination should include the following:
  • Vital signs
  • Examination of all skin areas, including areas not involved such as these:
    • Armpits
    • Under the breast
    • Feet
    • For women, the vaginal area
• Tests that may be performed include these:
  • Examination of your skin with a Wood's lamp (a source of long wavelength ultraviolet light)
  • Skin scrapings to be examined under the microscope
  • Fungal cultures
  • Laboratory tests such as a blood sugar level or complete blood count

Specific treatment depends upon the precise cause of the dermatitis (friction, humidity, with or without infection).

If you have some itching and redness in the groin area, try to keep the area dry, exposed to air as much as possible, and avoid tight clothes on the area. The symptoms may be relieved by applying a small amount of 1% hydrocortisone cream followed by a thick layer of zinc oxide ointment to the affected area for three to four days. If this is ineffective, you may apply an antifungal medication to the affected area.

Many antifungal medications are available without prescription. They come in cream, liquid spray, ointment, and powder forms. Some people may develop an allergic reaction to the medication, so stop using them if your rash seems worse.

• Tolnaftate (Tinactin, Aftate) and undecylenate (Cruex, Desenex) are well-known, effective medications. The powder form is also useful as a drying agent. These medications are not effective against candidal infections.
• Clotrimazole (Fungoid, Lotrimin, Mycelex) and miconazole (Micatin, Monistat Derm) are also available over the counter and are very effective against all fungi.
• If these medications help, be sure to use them for two to four weeks to completely clear the infection.
• Keeping the affected area clean and bone dry helps to clear the infection.
• You may use the medications to prevent relapses as well.
• If topical antifungals are not effective, you should discontinue them at least one week prior to visiting your physician.

The doctor will prescribe the appropriate medication based on your history, physical examination, and laboratory tests.

• Skin creams or lotions will probably be the first-line therapy for any of the causes of jock itch. Which one is appropriate will depend upon your physician's diagnosis.
  • Prescription topical antifungal medications may come in the form of a cream, powder, gel, or spray for application to the skin. Some topical therapies are available over the counter. Miconazole (Micatin, Monistat Derm), tolnaftate (Aftate, Ting, Tinactin), clotrimazole (Lotrimin, Mycelex), and terbinafine (Lamisil) are some examples and probably are as effective as the medications available by prescription.
  • For the bacterial infection of the groin (erythrasma), either topical or oral erythromycin is very effective.
  • For jock itch that is not infected, application of nonprescription 1% hydrocortisone cream and a barrier cream like zinc oxide ointment is beneficial.
• Oral medications have a greater risk for side effects.
  • They will be reserved for extensive, severe, or chronic infections.
  • They may also be prescribed if topical therapy does not work. Commonly prescribed medications are itraconazole (Sporanox) and fluconazole (Diflucan).
  • You will use the medication for one to several weeks because fungal infections can take a long time to clear.

• Use any medication the way it is prescribed and for the length of time prescribed.
• Do not stop because the rash goes away quickly.
• If instructed to do so, follow up with your doctor to be rechecked even if the rash has completely gone away.

To prevent jock itch, try to keep your groin area clean and dry.

• Use cornstarch, powders, even antifungal powder, such as Desenex or Cruex, in the various skin folds.
• It is best to wear loose-fitting cotton underwear.
• From a public-health perspective, sterilizing linens by washing in hot soapy water with bleach can help in situations of communal bedding and bath linens.

• Most cases of jock itch go away completely but commonly return if the physical environment recurs.
• An infection may come back for some people.
• In others, it may become chronic.