keloid is the formation of a type of scar which is a result of an overgrowth of granulation tissue (collagen type 3) at the site of a healed skin injury which is then slowly replaced by collagen type 1. Keloids are firm, rubbery lesions or shiny, fibrous nodules, and can vary from pink to the colour of the patient's flesh or red to dark brown in colour. A keloid scar is benign and not contagious, but sometimes accompanied by severe itchiness, pain,and changes in texture. In severe cases, it can affect movement of skin. Keloids should not be confused with hypertrophic scars, which are raised scars that do not grow beyond the boundaries of the original wound.Although they usually occur at the site of an injury, keloids can also arise spontaneously.Keloids expand in claw-like growths over normal skin.They have the capability to hurt with a needle-like pain or to itch without warning, although the degree of sensation varies from person to person.
Keloids can develop in any place where an abrasion has occurred. They can be the result of pimples, insect bites, scratching, burns, or other skin trauma. Keloid scars can develop after surgery. They are more common in some sites such as the central chest, the back and shoulders and the ear lobes. They can also occur on body piercings. Keloids tend to have a genetic component, which means you are more likely to have keloids if one or both of your parents has them. Keloids affect both sexes equally, although the incidence in young female patients has been reported to be higher than in young males, probably reflecting the greater frequency of earlobe piercing among women. The frequency of occurrence is 15 times higher in highly pigmented people. Children under 10 are less likely to develop keloids, even from ear piercing. The most important risk factor for the development of abnormal scars such as keloids is a wound healing by secondary intention, especially if healing time is greater than 3 weeks. Wounds subjected to a prolonged inflammation, whether due to a foreign body, infection, burn, or inadequate wound closure, are at risk of abnormal scar formation. Areas of chronic inflammation, such as an earring site or a site of repeated trauma, are also more likely to develop keloids. Occasionally, spontaneous keloids occur without a history of trauma.
The best treatment is prevention in patients with a known predisposition. This includes preventing unnecessary trauma or surgery (including ear piercing, elective mole removal), whenever possible. Any skin problems in predisposed individuals (e.g., acne, infections) should be treated as early as possible to minimize areas of inflammation.The decision to treat a keloid can be a tricky one—keloid scarring is the result of the body’s attempt to repair itself. Removing the keloid may mean that scar tissue only grows back again, sometimes larger than before.Examples of keloid treatments include:
- corticosteroid injections to reduce inflammation
- moisturizing oils to keep the tissue soft
- using pressure or silicone gel pads after injury
- freezing the tissue to kill skin cells
- laser treatments to reduce scar tissue
- radiation to shrink keloids
- surgery to remove the keloid
These treatments can reduce or eliminate keloid scarring.
Pharmacological therapy has long been a mainstay and relatively effective first-line therapy of treatment of keloids, either as sole treatment or in combination with other therapies. Intralesional steroid injections apparently act by diminishing collagen synthesis, decreasing mucinous ground substance, and inhibiting collagenase inhibitors that prevent the degradation of collagen, thus significantly decreasing dermal thickening. This is accomplished by uniform injection of 10-40 mg/mL of triamcinolone acetonide into the fresh site of scar excision with a 25- to 27-gauge needle at 4- to 6-week intervals until the scar flattens and discomfort is controlled. The steroid should be injected into the papillary dermis (where collagenase is produced). Avoid injection into the subcutaneous tissues, which causes fat atrophy and undercuts the intended purpose.
Simple excisional surgery should involve the least amount of soft tissue handling to minimize trauma; also, plan the closure with minimal skin tension along relaxed skin tension lines. In an effort to reduce wound tension, both full- and split-thickness skin grafts have been used, but these have been only partially successful. Make all attempts to remove any source of postoperative inflammation, such as trapped hair follicles, foreign material, hematomas, or infectious areas.
Complete excision along with intralesional steroid injection is the most effective therapy to prevent recurrence.