Keloid

Keloid
Classification and external resources
ICD-10 L91.0
ICD-9 701.4
MeSH D007627

A keloid is a type of hypertrophic scar with mainly type I and some type III collagen 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 scar is benign, non-contagious, and usually accompanied by severe itchiness, sharp 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.)

Contents

Occurrence

Keloid
Earlobe keloid as a result of piercing

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. It is speculated that people who possess any degree of African descent, regardless of skin color, may be especially susceptible to keloid occurrences.

History in medicine

Keloids were described by Egyptian surgeons around 1700 BC. Baron Jean-Louis Alibert (1768-1837) identified the keloid as an entity in 1806. He called them cancroide, later changing the name to cheloide to avoid confusion with cancer. The word is derived from the Greek chele, meaning crab's claw, and the suffix -oid, meaning like. For many years Alibert's clinic at the L'Hôpital Saint-Louis was the world’s center for dermatology.

Intentional keloids

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 even surgery.

Incidence

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 pseudofoliculitis 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 man 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.. Type A blood

Treatments

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.

Case presentation

This is a young male with bilateral keloid formation on the plantar surfaces of both feet. He has never been treated for this condition. There are other much smaller keloids located at small inlets on the glabrous(hairless) skin.

Plantar keloid formation
Plantar keloid formation
Plantar keloid formation

References

  1. Ogawa R, Mitsuhashi K, Hyakusoku H, Miyashita T. (2003). "Postoperative electron-beam irradiation therapy for keloids and hypertrophic scars: retrospective study of 147 cases followed for more than 18 months.". Plast Reconstr Surg. 111 (2): 547–53 & 554–5. doi:10.1097/01.PRS.0000040466.55214.35. PMID 12560675. 

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