Group 1: Sweaty Eczema (汗疱疹) - Sweaty eczema typically appears on palms and fingers, characterized by clusters of small blisters resembling water droplets [2] - It is a type of eczema that is highly prevalent in late spring and early summer, with symptoms including intense itching, pain from blister fluid, symmetrical distribution, and a tendency to recur [3][4] - Factors contributing to sweaty eczema include allergic reactions to metals, fungal infections, and lifestyle factors such as stress and poor sleep [4][5][6] - Treatment is generally self-limiting, with symptoms resolving in about two weeks if triggers are avoided [7] Group 2: Heat Rash (痱子) - Heat rash, also known as prickly heat, occurs when sweat cannot evaporate due to high temperatures and humidity, leading to inflammation [23][24] - Adults can also suffer from heat rash, especially those in high-temperature jobs or with certain health conditions [25][26] - The most common types of heat rash include white, red, and pustular types, each with distinct characteristics [27][28] - Proper management involves keeping the skin cool and dry, using mild cleansing products, and potentially applying calamine lotion [30][31][32] Group 3: Athlete's Foot (脚气) - Athlete's foot is a fungal infection characterized by itching, peeling, and blisters, often exacerbated in hot and humid conditions [35] - It is important to differentiate between foot odor and athlete's foot, as not all foot odor indicates a fungal infection [36] - Common misconceptions about treatment include the ineffectiveness of vinegar and iodine foot soaks, which do not adequately address the fungal infection [38][39][40] - Effective treatment requires antifungal medications, and adherence to the full treatment course is crucial to prevent recurrence [44]

Core Viewpoint - The article discusses the increase in patients presenting with "small blisters" on hands and feet during the summer, primarily caused by various skin conditions, with a focus on sweat eczema as the most common cause [1][2]. Group 1: Common Conditions - The most common condition leading to "small blisters" is sweat eczema, characterized by small blisters on the palms and soles, often accompanied by severe itching [2][3]. - Other potential causes include athlete's foot, hand-foot eczema, contact dermatitis, and hand-foot-mouth disease, each with distinct characteristics and treatment approaches [3][4]. Group 2: Symptoms and Diagnosis - Patients typically experience blisters on the sides of fingers, palms, and soles, with symptoms worsening at night or with heat, leading to potential secondary infections if scratched [2][3]. - Sweat eczema is noted for its self-limiting nature, often exacerbating in summer and improving in fall and winter, with recurrent episodes leading to skin thickening and cracking [2][3]. Group 3: Treatment Approaches - Treatment for sweat eczema focuses on symptomatic relief, with options like calamine lotion for itching and topical corticosteroids for severe cases [6]. - Athlete's foot requires maintaining dry skin and may involve antifungal medications, with an emphasis on completing the full treatment course to prevent recurrence [6]. - Hand-foot eczema treatment involves avoiding irritants and may include wet dressings during acute phases, transitioning to topical corticosteroids as the condition stabilizes [6]. - Contact dermatitis treatment emphasizes identifying and removing the irritant, followed by appropriate topical or oral medications as needed [6][7].