Tinea Cruris is a type of dermatophytosis which affects the area of the groin and adjacent skin. It is known with many names including crotch itch, crotch rot or jock itch.
Tinea cruris usually affects the inner thighs and genitals but can often spread to the perineum and perianal area. The acute infection begins as a series of sores in the groin region (each about half inch wide) which then take the appearance of a rash with sharply defined borders that can later blister and exude . Patients report an intense itch in the affected body part (usually associated with a burning sensation) and a recent history of related episodes like visits to tropical countries or wearing tight-fitting clothes. People living in situations in which sharing is highly possible, for instance prison inmates, comrades in armed forces and members of athletic teams, have an additional risk of contracting the disease.
The main diagnostic method for tinea cruris is microscopy, usually with the use of potassium hydroxide (KHO) to help dissolve keratin and other debris. The specimen can then be sent to a laboratory to confirm or identify the fungal species responsible for the infection. Rarely, biopsy might be needed in atypical cases which do not properly respond to treatment.
Tinea cruris can be best treated by using antifungal medications of the imidazole or allylamine family (e.g. terbinafine and naftifine) . Topical steroids and Whitfield’s ointment can be also used but their benefits are still not clear and they are not recommended by specialized guidelines . Prevention is highly advised especially in those individuals with a history of dermatophyte infections on feet and hands.
Usually, the prognosis of tinea cruris is excellent but the risk of recurrence is very high. Therefore, subjects who have been affected by this infection are advised to take the appropriate precautions like daily groin washing, frequent underwear change and especially constant check of the feet as the skin between the toes is flaky and thus, more inclined to fungal infections.
This is a classical example of opportunistic infection which takes advantage of any temporary or permanent weakness of the immune system. The most common etiologic agents of tinea cruris are the species which normally live on the surface of the epidermis causing no problem in immunocompetent people. Notable among them are Trichophyton rubrum and Epidermophyton floccosum. These fungi may also grow on non-living objects (called fomites) such as towels, bedroom sheets and especially skin-tight garments like jock straps .
In addition to immune weakness, a number of other circumstances (like remaining in sweat-soaked clothes or experiencing a prolonged exposure to moisture after a workout or a game) can also favor the growth of these fungi. The humid conditions generated in these accidental situations favor the overgrowth of the fungal population which ultimately enters the superficial epidermal layers and leads to infection. The common name “jock itch” might give the false impression that this is a problem which only involves athletes.
Overweight people are frequently affected as the numerous folds of their skin offer a perfect environment for fungal growth. Wearing tight clothing also contributes to the development of tinea cruris because it causes sweating and prevents the skin from drying.
Like all the other members of the dermatophytosis family, tinea cruris is common all over the world; especially in countries with hot humid climates where it finds the perfect conditions to thrive .
While no mortality is associated with this disease, the morbidity is quite high and can be attributed to complications like lichenification, secondary bacterial infections and dermatitis. Tinea cruris is three times more frequent in men than in women. It is also more common in adults compared to children owing to scrotal anatomy and age-related disorders like obesity and diabetes mellitus.
The most common etiologic agents responsible for tinea cruris are the species belonging to the genus Trichophyton and the species Epidermophyton floccosum and Microsporum canis. They produce keratins that favor the invasion of the epidermal cornified layer. The infection is then encouraged by the damp and warm conditions of local environments like those within the above mentioned folds of the skin  . Tinea cruris can be transmitted through anthropophilic, geophilic and zoophilic spread. It most frequently infects the groin and its adjacent areas.
The main recommendation to prevent tinea cruris is to always maintain good standards of hygiene for nails and skin, especially in the groin area which should be kept clean and dry by drying off after bathing and putting on dry clothing after athletic activities. It is also recommended to wear loose cotton underwear and avoid the aforementioned tight-fitting clothes together with using antifungal powders and avoding the sharing of clothes and towels .
Tinea cruris can be acute, subacute or chronic and is specifically located between the intertriginous folds in the area around the groin, scrotum and less frequently the penis, vulva and anus. The infection affects both sexes - though it is more often seen in adult men. Like the other types of dermatophytosis, tinea cruris tends to grow with a characteristic ring-like pattern on the skin for which it is often referred to as ringworm.
Tinea Cruris is a skin infection of the area of the groin and adjacent skin in any sex. It tends to grow onward on the skin, producing a characteristic ring-like pattern, and characterizes itself to take advantage of temporary favourable conditions such as a weakening of the immune system.
The most common etiologic agents of tinea cruris are the species of fungi which live on the surface of the skin. These organisms thrive in the favorable hot humid conditions generated in accidental situations like wearing tight clothing and experiencing a prolonged exposure to moisture. In these occasions, fungi can enter the superficial epidermal layers and cause infection.
Tinea cruris can be easily treated by using antifungal medications, but recurrence is very frequent and appropriate precautions like using antifungal powders should always be employed.