A 64-year-old black woman presents to the office with itching keloids on her chest (Figure 213-1). The horizontal keloid started during childhood when she was scratched by a branch of a tree. The vertical keloid is the result of bypass surgery 1 year ago. The lower portion of this area could be called a hypertrophic scar, as it does not advance beyond the borders of the original surgery. The patient was happy to receive intralesional steroids to decrease her symptoms. Intralesional triamcinolone did, in fact, decrease the itching and flatten the vertical keloid.
Two keloids that cross the chest of a 64-year-old black woman. The horizontal keloid came from a scratch during childhood, and the vertical keloid is a result of open-heart surgery. (Reproduced with permission from Richard P. Usatine, MD.)
Keloids are benign dermal fibroproliferative tumors that form in scar secondary to altered wound healing. Keloids are characterized by their nature of extending beyond the original area of injury. They form as a result of overproduction of extracellular matrix and dermal fibroblasts that have a high mitotic rate.
Individuals with darker pigmentation are more likely to develop keloids. Sixteen percent of black persons reported having keloids in a random sampling.1
Men and women are generally affected equally, except that keloids are more common in young adult women—probably secondary to a higher rate of piercing the ears (Figure 213-2).2
There is evidence for a family tendency in developing keloids; studies thus far have suggested autosomal dominance with incomplete penetrance.3
Rare in extremes of age; highest incidence is in individuals ages 10 to 20 years.2,4
A keloid on the earlobe that started from piercing the ear. (Reproduced with permission from Richard P. Usatine, MD.)
ETIOLOGY AND PATHOPHYSIOLOGY
Keloids are dermal fibrotic lesions that are a variation of the normal wound-healing process in the spectrum of fibroproliferative disorders.
Keloids are more likely to develop in areas of the body that are subjected to high skin tension such as over the sternum (see Figure 213-1).
May occur up to a year after the injury and will enlarge beyond the scar margin. Burns and other injuries can heal with a keloid in just one portion of the area injured (Figure 213-3).
Wounds subjected to prolonged inflammation (acne cysts) are more likely to develop keloids.
A keloid on the arm of a Hispanic woman burned accidentally by a hot iron at the age of 1 year. Most of the burn scar is not a keloid. The keloid is ...