What causes tinea manuum and tinea pedis?

Tinea manuum and tinea pedis are common dermatological conditions primarily caused by the combined effects of various factors. Specifically, the main causes of tinea manuum and tinea pedis include: 1. **Fungal infection**: Tinea manuum and tinea pedis are mainly caused by fungal infections, with common fungi including dermatophytes and molds. These fungi can spread through direct contact, such as sharing towels, gloves, shoes, or other personal items with infected individuals, or by contacting contaminated objects in public baths, swimming pools, and other public places. 2. **Skin damage**: When the skin suffers abrasions, cuts, or other injuries, fungi can easily enter the skin through the wounds and multiply, leading to infection. 3. **Humid environment**: Tinea manuum and tinea pedis are more likely to occur in humid environments. Moist conditions provide an ideal environment for fungal growth; therefore, the incidence of these infections is higher during seasons or in environments characterized by excessive sweating and humidity. 4. **Weakened immune system**: A weakened immune system is another contributing factor to tinea manuum and tinea pedis. Immunosuppression may reduce the skin's resistance to fungal infections, making individuals more susceptible. This may be associated with underlying chronic diseases (such as diabetes or liver disease) or long-term use of corticosteroids and other immunosuppressive medications. 5. **Genetic factors**: Tinea manuum and tinea pedis also exhibit a certain degree of heritability. Individuals with a family history of these conditions are more likely to develop them.