The redness, swelling, hardness, warmth and itching of the calves may be caused by trauma, urticaria, dengue and so on. 1. Trauma: If there is a trauma before the occurrence of calf redness, swelling, hardness, fever, itching and localized obvious redness, swelling, hardness, fever, itching, should be considered to be caused by trauma, this kind of people should consult a doctor in a timely manner, under the guidance of the doctor for further treatment of wounds. 2. Urticaria: if the patient in the occurrence of calf redness, swelling, hardness, fever, itching before contact with their own allergic substances such as mango, seafood, pollen, etc., it should be considered to be caused by urticaria, such patients may be serious if the redness, swelling, skin temperature rise, severe itching and other symptoms. Such people should avoid contact with allergens, and use drugs such as loratadine under the guidance of a doctor for treatment. 3. Dengue: due to hemolytic streptococcus and other infections, there may be redness, swelling, heat and pain, local redness, swelling, surface tension and shining. The symptoms of redness, swelling, hardness, heat and itchiness of the calf should be timely medical treatment, clear cause for treatment.