Scrofula is a form of tuberculosis involving the skin due to direct spread, usually from the spread of deep tuberculous lymphadenitis, most commonly in the cervical lymph nodes. The rash at first appears as a subcutaneous mass, which gradually increases in size to form a nodule, which is mostly red, or may be of normal color, with a low skin temperature; as the disease progresses, the nodule may become suppurated and break down, forming a sinus tract or ulcer, with reddish granules at the base of the ulcer. The scrofula heals to form a striated scar, which is the characteristic damage.