A keloid is a special type of scar which results in an overgrowth of tissue at the site of a healed skin injury. Keloids are firm, rubbery lesions or shiny, fibrous nodules and can vary from pink to flesh-colored or red to dark brown in color. A keloid, sometimes referred to as a keloid scar, is a tough heaped-up scar that rises quite abruptly above the rest of the skin. It is irregularly shaped and tends to enlarge progressively. Keloids usually result from skin injury or burns. Pimples, insect bites, scratching, chickenpox scarring etc. may also cause keloids. They may also be caused by infection at a wound site, repeated trauma to an area, excessive skin tension during wound closure or a foreign body in a wound. They can occur at the site of a piercing and have been found on the earlobes, eyebrows, chest and other sites of piercing. Keloids commonly occur on the shoulders, chest, arms and upper back even when there has been no apparent injury. However, they can appear almost anywhere.
A keloid may extend beyond the site of injury. Keloids respond poorly to therapy, but monthly injections of corticosteroids may flatten them somewhat. A doctor may try surgical or laser removal followed by corticosteroid injections, but new keloids often form in the scar resulting from the treatment.
Keloids can be considered to be ” scars that don’t know when to stop.” When the skin is injured, cells grow back to fill in the gap. Somehow, they normally “know” when the scar tissue is level with the skin, at which point the cells stop multiplying. When the cells keep on reproducing, the result is a what is called a overgrown (hypertrophic) scar or a keloid. In other words, keloids are due to an excessive response to trauma such as a cut to the skin. In creating a normal scar, connective tissue in the skin is repaired by the formation of collagen. This occurs in the dermis (the layer of skin just below the epidermis, the outer layer of skin). Keloids arise when there is too much collagen formed in the dermis during the repair of connective tissue. To develop keloids, a person must be susceptible to keloid formation.
The cause of keloids is unknown. A keloid can be caused by injury to the skin, such as a burn, insect bite, acne, cut, body piercing, or a surgical incision. Scar tissue normally grows in response to a wound, but a keloid is an overgrowth of scar tissue over a healed wound. Some people have a genetic tendency to develop keloids.
Find common causes and risk factors of Keloids:
Sign and symptoms may include the following:
Treatment may include: