Are the small red spots on the soles of the feet eczema or athlete’s foot?

Small red spots on the soles of the feet may indicate either eczema or tinea pedis (athlete’s foot); the specific diagnosis depends on multiple factors and may be caused by fungal infection, eczema, allergic dermatitis, syphilis, or other conditions.

1. Fungal infection: Causes tinea pedis (commonly known as athlete’s foot). After fungal infection of the foot skin, local inflammatory reactions occur, leading to dilation and congestion of small blood vessels—resulting in erythematous patches on the soles, accompanied by symptoms such as vesicles, pruritus, and scaling.

2. Eczema and allergic dermatitis: Triggered by various internal and external allergens—for example, direct contact with allergenic substances on the skin or ingestion of allergenic foods or medications—which can provoke an allergic reaction in the feet, manifesting as small red spots and marked pruritus. Certain systemic diseases may also cause plantar erythema; for instance, erythema multiforme—a hypersensitivity disorder—typically presents with target-shaped erythematous lesions on the palms and soles, often with central vesicles.

3. Syphilis: In secondary syphilis, characteristic copper-red, infiltrative macules appear on the palms and soles. These lesions are typically asymptomatic (neither painful nor itchy) and may exhibit superficial desquamation. Clinical suspicion should prompt appropriate serological testing for syphilis.

In daily life, maintaining good hygiene habits—including washing the feet morning and evening—is essential.