For most people, when they cut themselves shaving the wound will become slightly inflamed, scab over, and maybe leave a tiny scar. But for approximately 4% to 6% of patients, the healing process goes too far, resulting in thick, raised scars known as keloids.
Keloids can arise from cuts, burns, chickenpox, acne, and piercings. Patients who develop keloids, might wind up with scars much larger in width and height than the original injury. Over months or years, scars can grow from the size of a pencil top eraser to a grapefruit or larger.
Patients tend to first notice symptoms between ages 10 and 30, with the 20s as the prime age to develop keloids. The condition can range from mildly annoying to socially limiting. Research suggests that keloids affect patients’ quality of life similarly to psoriasis. While some patients don’t mind their scars, others are very bothered by them, finding it impossible to camouflage facial keloids. Others have told us keloids have compelled them to keep their arms and legs covered.
Scarring can also cause physical issues. 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.
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.
What causes keloid scars?
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.
In other words, their bodies ‘overheal’ with excessive scar tissue.
Researchers think there might be genetic factors associated with keloid scarring, and we are on the cutting-edge of this developing field of study. UT Southwestern is building a database of patient information to help determine whether there are genetic components related to keloid scarring.
Patients with keloids who agree to contribute to the database answer a short questionnaire about their condition and family history. We also draw a blood sample to examine their DNA and take photos of their scars for observation. If we can identify genetic mutations in patients who keloid, we might one day be able to screen families, correct the mutation, and prevent or dramatically reduce instances of the condition.
Preliminary data indicate that when keloids appear to run in families, approximately half of family members keloid and the other half doesn’t. Research also suggests that genetic mutations potentially associated with keloids might skip a generation, which is known as incomplete penetrance. For example, a parent might never keloid but might pass the genetic mutation on to their child.
We’ve also observed variable expressivity, in which family members who keloid do not always develop the same intensity of scars or in the same area of the body, such as the face, chest, arms, or groin.
Today, researchers have a small amount of data for East Asian ethnicities (including Japanese and Chinese Han populations) and one gene has been identified in one Nigerian family as potentially associated with keloids. Over time, we hope to amass enough data to sort by patient demographics such as ethnicity to provide clues as to why certain populations are more prone to developing the condition.
Who gets keloids?
We know keloids disproportionately affect people of color, especially those of African and Hispanic descent. 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.
Right now, the only way we know for sure whether a patient keloids is if they come to see us with one. However, individuals who develop keloids in one area of the body might never get them in another. The general rule is if a patient keloids on the chest, shoulders, or back, they might be more likely to keloid on the stomach, arms, scalp, and elsewhere.
Keloids below the elbow are knee are relatively rare. Patients who keloid in these areas should assume that any surgery, cut, or inflammation will likely trigger a keloid. We’ve found that patients in this group tend to be more proactive about using coverings, creams, and ointments on wounds and are generally more careful about avoiding injury. These patients also are less likely to get tattoos and piercings or undergo elective surgery.
What treatments are available?
Treatment for existing keloids
Whether a patient is concerned about their appearance, physical discomfort, or both, treatment must be approached thoughtfully.
Surgery might be an option for some patients. However, removed scars can return – and sometimes with a vengeance. Remember, keloids form due to overhealing. We’ve seen cases in which the surgical scar came back twice as large (or more) as the original keloid. This can be especially difficult for patients who have scars on the face, ear, arm, or another visible area. These patients can get caught up in a cycle of surgery-regrowth-surgery if their provider does not intervene.
That said, surgery for unrelated medical conditions is sometimes necessary, which can result in a keloid scar. For example, if a patient needs open heart surgery, they might develop a keloid in the center of the chest. We’ve had patients say their scars make it painful to even wear a seatbelt properly, which affects their safety and quality of life. Similar scenarios can occur if a patient needs a thyroid procedure, cesarean section, or other type of surgery. Post-surgical treatments are necessary to decrease the risk of occurrence/recurrence.
Other treatments for existing keloids can include:
- Corticosteroid injections, which can reduce the size and itching of scars.
- Cryotherapy, which involves freezing the scar tissue from either the outside (topically) or the inside (with a probe).
- Laser therapy, which uses a narrow beam of high-intensity light to shrink or remove layers of skin.
Preventing new keloids
- Compression to the area can help prevent the development of a new keloid after surgery. Patients will wear pressure earrings or garments for six to 12 months to prevent a keloid or potentially develop a smaller keloid.
- Anti-inflammatory steroid injections administered into a new scar can help reduce inflammation, which seems to play a role in keloid development.
- Silicone sheets, which resemble bandages without the gauze pad, can be applied to new wounds to reduce the risk of developing a keloid. However, these special sheets do not reduce the size of existing keloids.
When do I need advanced care?
Patients who develop keloids despite seeking preventive treatments should consider visiting a specialized center such as UT Southwestern.
We can offer advanced treatments, including chemotherapy-based agents to kill cells that actively overproduce collagen. For patients with pain and itching, we can also offer pentoxifylline, an oral drug that is approved by the Food and Drug Administration to treat poor blood flow. We’re currently examining whether this drug can reduce such symptoms, and preliminary data are promising.
Because we are an academic medical center, our dermatologists collaborate with other departments to create unique care plans. We regularly partner with colleagues in plastic surgery and radiology on patient-specific precautions before and preventative procedures after surgery to reduce patients’ risk of keloid recurrence.
Whether a patient needs preventive care or advanced treatment, a team-approach from keloid experts can deliver the best results. To visit with a specialist, call 214-645-8300 or request an appointment online.
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