What it looks like and how it differs
The lesions begin in the inguinal fold and spread to the inner surface of the thighs in the form of semicircular spots. The edge of the lesion is brighter, slightly raised, often with small blisters or peeling, and the center gradually fades - a characteristic ring-shaped pattern is obtained. I am concerned about itching, sometimes burning, which intensifies with sweating. It is typical for dermatophytes that the scrotum remains free, whereas with candidiasis it is usually involved, and the rash is bright red, moist, with small spots along the periphery.
- Spots with a distinct raised edge
- Pallor in the center of the lesion
- Peeling and small blisters around the edges
- Itching, worse with sweating
- The scrotum is usually not affected
- Spread to inner thighs
Where does it come from?
The causative agents are dermatophytes, the same fungi that cause damage to the feet and nails. Very often the source is one’s own feet: a person puts on underwear after wearing socks, and the fungus is transferred to the groin. Infection is possible through shared towels, washcloths, benches in bathhouses and gyms, and other people's shoes and clothes. The development of the disease is facilitated by everything that creates a greenhouse effect in the wet fold: heat, synthetic underwear, excess weight, prolonged sitting. The disease is worse with diabetes and reduced immunity.
- Transfer of fungus from feet and nails
- Shared towels and washcloths
- Baths, swimming pools, gyms
- Heat and excessive sweating
- Tight synthetic underwear
- Excess weight and skin folds
- Diabetes mellitus
Diagnostics
An experienced dermatologist often recognizes the disease by its appearance, but confirmation is important because similar rashes are caused by candidiasis, erythrasma, psoriasis of the folds and seborrheic dermatitis, and their treatment is different. A scraping of scales is taken from the edge of the lesion and examined under a microscope; if necessary, a culture is done to determine the type of fungus. The examination must be extended to the feet and nails: without their treatment, relapse is almost inevitable. If the course is persistent or widespread, blood glucose is checked.
- Examination of lesions and entire skin
- Microscopy of scraping from the edge of the lesion
- Sowing on a nutrient medium
- Examination of feet and nails
- Examination under a Wood's lamp for suspected erythrasma
- Blood glucose with persistent flow
Treatment
The basis is external antifungal agents in the form of a cream, which are applied to the lesion and 2 centimeters of healthy skin around it, usually for 2-4 weeks. It is impossible to stop treatment immediately after the itching disappears: the fungus remains in the stratum corneum, and the rash returns. In case of extensive damage, frequent relapses and concomitant nail damage, the doctor adds a systemic antifungal drug. Combined ointments with hormones are used briefly and only for their intended purpose: they quickly relieve itching, but with prolonged use they mask the infection and worsen the course.
- Topical antifungal creams 2–4 weeks
- Treatment by grasping healthy skin around
- Continue treatment after symptoms disappear
- Systemic drugs for a common process
- Simultaneous treatment of foot and nail fungus
- Hormonal ointments - only for a short course as prescribed
Relapse Prevention
The fungus returns where heat and moisture are retained, so the main task is to keep the folds dry. After a shower, the skin should be thoroughly dried, especially in the groin, and only then get dressed. Loose cotton underwear, changing underwear and socks daily, washing at high temperatures and ironing are helpful. An important rule: put on socks first, and then panties, so as not to transfer foot fungus. In the bathhouse and swimming pool, use personal slippers and a towel, and if you are prone to sweating, use powders and drying agents.
- Thorough drying of folds after shower
- Loose cotton underwear
- Daily change of underwear and socks
- High temperature wash and ironing
- First socks, then underwear
- Personal slippers and towel in public places
- Weight and blood sugar control