The fundamental cause of erysipelas is mainly due to a streptococcal infection of the lymphatic vessels, causing acute non-purulent inflammation. Patients with erysipelas often may have underlying conditions such as athlete's foot, ulcers, or other infectious foci. Erysipelas is prone to develop secondary to ulcers, trauma, or some purulent infections, spreading directly from these primary diseases through the skin, mucous membranes, lymphatic channels, or hematogenous invasion.