Neck red, swollen, itchy, there is a lump may be due to mosquito bites, folliculitis and lymph node inflammation and so on. 1. Mosquito bites: mosquitoes bite the neck, will be injected into the subcutaneous toxins, these toxins can lead to local skin immune response, which in turn leads to capillary dilation, increased permeability of the blood vessel wall, so the neck will be red, swollen, itchy, there is a lump. 2. Folliculitis: when the hair follicles on the neck are blocked by oil, bacterial or viral infection, can trigger local skin inflammation, inflammatory factors will stimulate local vasodilatation, skin cells and tissue fluid exudation, which can cause the neck red, swollen, itchy, a lump. 3. Inflammation of lymph nodes: If the lymph nodes in the neck are inflamed, resulting in lymph node enlargement, so that the lymphatic reflux is not smooth, the local mass can be formed. And because of the infiltration of inflammatory cells, can make the local skin red, swollen, itchy. If your neck is red, swollen, itchy and has a lump, you should go to the hospital as soon as possible, and the doctor will formulate a treatment plan according to your specific condition.