A circle of round ringworm on the arm may be caused by fungal infection, coin eczema, psoriasis and other reasons.
1. Fungal infection: after the arm skin is infected with fungus, the fungus will use the stratum corneum as the raw material to multiply and proliferate, forming a certain inflammatory reaction, which will lead to the emergence of papules and papules, and gradually expand to the surrounding area to form a circle-like change.
2. Coin-shaped eczema: the cause of the disease is not clear, mainly localized inflammatory skin allergic reaction, clinical manifestations of small papules and papules fused into round or similar round coin-shaped patches, and accompanied by itching symptoms.
3. Psoriasis: the cause is more complex, can cause arm skin flaky red patches, round, covered with silvery-white scales, scraping off the scales can be seen thin film phenomenon, as well as point-like hemorrhage, and accompanied by itching.
Caused by a circle of ringworm on the arm of the patient more reasons, it is recommended that patients go to the hospital in a timely manner, clear causes for targeted treatment.