Keloid (Keloidal Scar)
A keloid (also known as a "keloidal scar") is a type of scar, which depending on its maturity, is composed of mainly either type III (early) or type I (late) collagen. It 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 flesh-coloured or red to dark brown in colour. A keloid scar is benign, non-contagious, and sometimes accompanied by severe itchiness and pains, 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.
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 patient to patient.
If the keloid becomes infected, it may ulcerate. The only treatment is to remove the scar completely. However, the probability that the resulting surgery scar will also become a keloid is high, usually greater than 50%.
Keloids form within scar tissue. Collagen, used in wound repair, tends to overgrow in this area, sometimes producing a lump many times larger than that of the original scar. Although they usually occur at the site of an injury, keloids can also arise spontaneously. They can occur at the site of a piercing and even from something as simple as a pimple or scratch. They can occur as a result of severe acne or chickenpox scarring, infection at a wound site, repeated trauma to an area, excessive skin tension during wound closure or a foreign body in a wound. Keloids can sometimes be sensitive to chlorine.
Biologically, keloids are fibrotic tumors characterized by a collection of atypical fibroblasts with excessive deposition of extracellular matrix components, especially collagen, fibronectin, elastin, and proteoglycans. Generally, keloids contain relatively acellular centers and thick, abundant collagen bundles that form nodules in the deep dermal portion of the lesion. Keloids present a therapeutic challenge that must be addressed, as these lesions can cause significant pain, pruritus (itching), and physical disfigurement. They may not improve in appearance over time and can limit mobility if located over a joint.
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. There is a fifteen times higher frequency of occurrence in highly pigmented people. Persons of African descent are at increased risk of keloid occurrences.
History in medicine
Keloids were described by Egyptian surgeons around 1700 BCE. Baron Jean-Louis Alibert (1768–1837) identified the keloid as an entity in 1806. He called them cancroïde, later changing the name to chéloïde to avoid confusion with cancer. The word is derived from the Greek χηλή, chele, meaning "hoof", here in the sense of "crab pincers", and the suffix -oid, meaning "like". For many years, Alibert's clinic at L'Hôpital Saint-Louis was the world’s center for dermatology.
The Olmec of Mexico in pre-Columbian times used keloid scarification as a means of decoration. In the modern era, women of the Nubia-Kush in Sudan are intentionally scarified with facial keloids as a means of decoration. The Nuer and Nuba use lip plugs, keloid tattoos along the forehead, keloid tattoos along the chin and above the lip, and cornrows. As a part of a ritual, the people of Papua, New Guinea cut their skin and insert clay or ash into the wounds so as to develop permanent bumps (known as keloids or weals). This painful ritual honors members of their tribe who are celebrated for their courage and endurance.
Locations of keloids
Keloids can develop in any place that 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 central chest, the back and shoulders and the ear lobes.
People of all ages can develop a keloid. Children under 11 are less likely to develop keloids, even when they get their ears pierced. Keloids may also develop from pseudofolliculitis barbae, continued shaving when one has razor bumps will cause irritation to the bumps, infection and over time keloids will form. It would thus be wise for a person with razor bumps to stop shaving for a while and have the skin repair itself first before undertaking any form of hair removal. It is also speculated that the tendency to form keloids is hereditary and may be passed down from generation to generation.
No treatment for keloids is considered to be 100% effective. Some of the treatments that are currently available are described below. These treatments have varying degrees of effectiveness. All the invasive methods of treatment like surgery carry a serious risk of the keloid recurring and becoming bigger than it previously was.
- Natural treatments — One clinically proven and drug free scar treatment option is silicone sheeting. Silicone sheeting is safe and effective in reducing existing scars and helping to prevent new scars in anyone age 3 and up. Some scar treatments contain mucin from the snail helix aspersa müller, however, there is a lack of clinical evidence of effectiveness of mucin. Effective natural scar treatments regulate the skin healing and scar formation process. Topical application of silicone treatments on keloid scars regulates and/or decreases dermal fibroblast proliferation and excess collagen production, and thus prevents and reduces keloid scars and hyperthropic scars.
- Surgery — Surgery requires great care during and after the operation. Keloids that return after being excised may be larger than the original. There is a 50% chance of recurrence after surgical removal. However, keloids are less likely to return if surgical removal is combined with other treatments. Surgical or laser excision may be followed by intralesional injections of a corticosteroid and/or coverage with a silicone scar sheet such as ScarAway. Using Silicone scar sheets such as ScarAway is clinically proven to reduce the occurrence of keloids and help reduce existing keloid scars.Plastic closure of the skin including techniques such as v-plasty or w-plasty to reduce skin tension are also known to reduce recurrence of keloids following excision.
- Dressings — Moistened wound coverings made of silicone gel (such as Dermatix and ScarAway) or silastic have been shown in studies to reduce keloid prominence over time. This treatment is safe and painless, some are even helpful in alleviating the itching often associated with keloids.
- Steroid injections — Steroid injections are best used as the scar begins to thicken or if the person is a known keloid former. A series of injections with triamcinolone acetonide or another corticosteroid may reduce keloid size and irritation. However, injections are often uncomfortable and in large and/or hard scars can be difficult to perform, requiring local anesthetic for people over 16, and full anesthetic for people under that age. The treatment area can become very painful as the anesthetic wears off.
- Compression — Compression bandages applied to the site over several months, sometimes for as long as six to twelve months, may lead to a reduction in the size of the keloid. Silicone Scar Sheets may be used safely under compression garments to aid in preventing new scars.
- Gels and creams. There are numerous gels and creams on the market that are little more than moisturizers and are not clinically proven to aid in scar reduction. Look for 100% silicone products such as ScarAway Serum (reduces scars but will not bleach skin). Another option is creams that contain onion extract such as Contractubex Gel, Mederma or Hexilak Gel — creams/gels gels with allantoin (exercise caution when using on highly pigmented skin as these types of products may lighten even surrounding healthy skin). These types of topical products are indicated for the treatment of all post traumatic (burns, acne, piercings) or post surgery scars and keloids. Treatment is simple but requires persistence. The earlier the initiation of treatment, the better the prognosis. Also grapfruit seed extract liquid concentrate, with exesive use, can help reduce size, and also for small keliods take them away, but it may not be permanent.
- Cryosurgery — Cryosurgery is an excellent treatment for keloids which are small and occur on lightly pigmented skin. It is often combined with monthly cortisone injections. The use of cryotherapy is limited since it causes skin blanching. It freezes the skin and causes sludging of the circulation beneath, effectively creating an area of localized frostbite. There is a slough of skin and keloid with re-epithelization.
- Radiation therapy — Electron beam radiation can be used at levels which do not penetrate the body deeply enough to affect internal organs. Orthovoltage radiation is more penetrating and slightly more effective. Radiation treatments reduce scar formation if they are used soon after a surgery while the surgical wound is healing. This is one of the most effective procedures.
- Laser therapy — This is an alternative to conventional surgery for keloid removal. Lasers produce a superficial peel but often do not reduce the bulk of the keloid. The use of dye-tuned lasers has not shown better results than that of cold lasers. A relatively new approach is to combine laser therapy with steroid injections and the use of Silicone Sheeting.
- Newer treatments — Drugs that are used to treat autoimmune diseases or cancer have shown promise. These include alpha-interferon, 5-fluorouracil and bleomycin. However, there is a need for further study and evaluation of this treatment technique.