Some researchers think it may be purely genetic; others think the prevalence in these populations has something to do with sun penetration and melanin, a dark pigment in the skin. Keloids are the result of excessive collagen production. Collagen is a substance produced by a type of skin cells called fibroblasts. These cells are found in the dermis, the deeper level of the skin. Patients who keloid have more dermis – and more cells that generate dermis – than patients who do not keloid.
It is particularly useful in monitoring the effectiveness of treatment. Keloid scars are raised above the skin around them and can take on the appearance of a dome-shape, extending beyond the original wound margin. They are often shiny and hairless, with varying consistency. During keloid formation, there is a prolonged inflammatory phase . This contributes to excess fibroblast activity and increased deposition of ECM, resulting in the tissue projecting beyond the original wound margin.
INF-alpha 2b appears to normalize the increased collagen synthesis and glycosaminoglycan production by keloid fibroblasts, resulting in a reduction in the size of the keloid by approximately 50%. Most of these adverse effects can be avoided by confining injections of the lowest possible dose of steroid to the dermal layer.
Avoid minor skin surgery to areas more prone to keloid scarring if possible. Treating acne will reduce the likelihood of acne scars appearing.
It has poor results, with recurrence rates between %. Surgical excision is thought to stimulate collagen synthesis – which results in the regrowth of a larger keloid. Surgical excision is thought to stimulate collagen synthesis – which results in the regrowth of a larger keloid. The Vancouver Scar Scale can be used to quantify features of any scar, including keloids.
Compression to the area can help prevent the development of a new keloid after surgery. Patients will wearpressure earrings or garmentsfor six to 12 months to prevent a keloid or potentially develop a smaller keloid. Corticosteroid injections, which can reduce the size and itching of scars. We know keloids disproportionately affect people of color, especially those of African and Hispanic descent.
Some evidence supports a relationship between genetic predisposition and an individual’s propensity to form keloid scars. Genetic associations for the development of abnormal scars have been found for HLA-B14, HLA-B21, HLA-BW16, HLA-BW35, HLA-DR5, HLA-DQW3, and blood group A.
There are generally few complications from keloidal scars. Depending on their appearance and location, they can cause some psychological distress, as keloids can be quite prominent. Keloids can also interfere with movement, especially if they are on a joint. They are often pink or red, or much darker or lighter in colour than the surrounding skin.
My UT Southwestern dermatology colleagues and I are working to identify genetic factors that increase the risk of keloid scarring. Our hope is to get to the root cause of keloids to improve standards of care and potentially prevent excessive scarring. Some patients experience limited mobility if the scars cross major joints, such as the shoulders, elbows, or knees. Approximately 75% of patients who keloid have intermittent itching, while about half have scar-related pain.
Keloids always extend beyond the limits of the original wound, sometimes by many centimetres. The colour, shape, and size of the scars may change with time. They are generally not painful, though they are often itchy.
You cannot completely prevent keloid scars, but you can avoid any deliberate cuts or breaks in the skin, such as tattoos or piercings, including on the earlobes. Colchicine inhibits collagen synthesis, microtubular disruption, and collagenase stimulation, and is thus used in the treatment of keloids. One of the newest therapeutic modalities is intralesional injection of INF-alpha, INF-beta, and INF-gamma. These mechanisms act by reducing the steady-state levels of mRNA. Studies examining the effects of intralesional injections of INF-alpha 2b and INF-gamma found them effective if injected immediately postoperatively into the excision site.