With the arrival of the rainy season, the climate is humid and tends to warm up gradually, and we are seeing more and more patients with ringworm in hospitals. This is because the fungus that causes ringworm prefers a warm and humid environment, so the disease tends to occur more easily or worsen in the late spring and early summer when the climate is humid or hot, and then remit or heal in the winter. A. Men and obese people are prone to ringworm. Ringworm is a common superficial fungal skin infection that occurs in the skin around the groin, perineum and anus, and is a special type of ringworm in the pubic and femoral areas. Tinea cruris occurs most often in men. In men, the inner femur is close to the scrotum, especially in obese people, and the two skin areas at the root of the thighs are completely attached together, and secretions and dirt on them are not easy to remove, and the high local temperature and humidity are very suitable for the growth and reproduction of fungi, so men are prone to ringworm. Women have relatively little tinea cruris, but if they are too obese and have a lot of skin folds on the vulva and the inside of the femur, when they sweat a lot and do not pay attention to cleaning, it is conducive to the growth of fungi, so tinea cruris can also occur in women. It can occur unilaterally or bilaterally at the same time. It begins as a slightly elevated erythematous patch with clear edges that gradually expands, becomes flaky, and gradually changes from red to brown or skin-colored. The central part of the lesion has a tendency to heal itself, while the edges of the erythematous patch are more inflamed and may have papules, blisters, crusts, or even erosions on them. The lesions develop to the periphery, forming a ring or semi-ring, which can leave temporary pigmentation after healing, often accompanied by obvious pruritic discomfort. If the disease is prolonged, infiltrative hypertrophic changes occur in the local skin. In severe cases, the lesions often extend to the inner femur, perineum, and perianal area, and their lower edges are more clearly defined. Sometimes the lesions can also spread to the scrotum, the root of the penis and other places. The occurrence of this disease is firstly related to the resistance of the patient’s organism. If the patient is bedridden and weak, especially if he or she has diabetes, malignant tumor, tuberculosis, or uses corticosteroids or immunosuppressants for a long time, ringworm is more likely to occur than in healthy people. In addition, when wearing tight underwear as well as chemical fiber underwear with poor breathability, or if you are often engaged in driving at high temperatures, this can lead to increased local temperature and sweating, which can make ringworm more likely to occur or aggravate existing ringworm. In addition, local hygiene can also affect the occurrence of this disease. The actual fact is that you will find a lot of people who are not willing to go to a regular hospital for privacy reasons, but use some topical drugs on their own, especially topical drugs that contain corticosteroid hormone preparations, such as dermatoprene, skin ease, and so on. This can play a temporary role in stopping the itch, but because corticosteroid preparations can reduce local immunity, the result will lead to the spread of lesions, spread and inflammation aggravated. Some patients with hormones for a longer period of time, can also occur local skin purplish-red atrophy-like changes. Other patients, in order to clear the lesions as soon as possible, do not take into account the thin and tender skin of the pubic and femoral area, and use some highly irritating topical drugs on their own, or scratch strongly and wash with hot water, resulting in irritating contact dermatitis or eczema-like changes in the pubic and femoral area, which can be manifested as oozing from the pubic and femoral area.