What is Hypertrophic Scarring Keloids?
Wound healing is usually a balanced process. However, when this balance is disrupted, unfavorable scars such as hypertrophic scars and keloids can appear. Both of these types of scars are raised, hard, and formed when too much of a protein called fibrinogen and another compound called collagen are produced during the healing process. They can lead to symptoms such as itchiness, pain, limited movement, and cosmetic concerns.
Even though hypertrophic scars and keloids may look similar, there are key differences between them. Hypertrophic scars stay within the area of the injury and may fade over time. On the other hand, keloids can expand beyond the original injury area and do not fade. Under a microscope, the collagen in hypertrophic scars appears wavy and organized, while in keloids, there is no distinct collagen pattern.
What Causes Hypertrophic Scarring Keloids?
Hypertrophic scars and keloids are abnormal types of scar that can appear after severe damage to the skin, including burns, surgery, insect bites, tattoos, acne, chickenpox, and piercings. This happens when an injury reaches deep enough to impact the underlying layer of the skin called the dermis.
While we don’t completely understand why these scars form, research suggests that a few factors may play a part. For example, some people think that high levels of inflammation in the body may make these kinds of scars more likely. Conditions that raise inflammation markers in the body are thought to increase the risk of developing these types of scars.
Similarly, it’s been suggested that sex hormones might influence the likelihood of getting keloids by causing inflammation, leading to the overproduction of collagen, a protein found in the skin. There’s also been talk about a potential link between high blood pressure and the number or size of keloids a person has, though the exact role of high blood pressure has yet to be confirmed.
Lastly, the amount of physical strain on the wound during its healing process seems to play a big part in the development of these scars. Increased tension and stress on the wound area raise the likelihood of abnormal scar formation.
Risk Factors and Frequency for Hypertrophic Scarring Keloids
Keloids are more likely to form in people who have a genetic tendency to them, and are most common in people with darker skin tones. The groups with the highest rates of keloids are African, Asian and Hispanic populations, with Caucasians having the least. Studies have found keloids in families over several generations and in twins, indicating that the risk of developing keloids may be passed down through genes.
On the other hand, hypertrophic scars, which are a type of thick scar, don’t seem to have a genetic component. Even so, they may be slightly more common in people with darker skin. They also have a tendency to form in areas where the skin is stretched a lot. The research shows that hypertrophic scars can occur in 39% to 68% of people after they’ve had surgery, and in 33% to 91% of people after they’ve been burned. While some studies suggest that women may get hypertrophic scars more often, others have found no such difference between men and women.
Both keloids and hypertrophic scars are most likely to occur in young people, between the ages of 11 and 30. This is believed to be because young people’s skin renews itself more quickly and produces more collagen, a protein that helps wound healing. In addition, young people’s skin is under more tension and their immune system is more active, compared to older people who have more elastic skin and a less active immune system.
Signs and Symptoms of Hypertrophic Scarring Keloids
Keloids and hypertrophic scars are both types of raised, thickened scars that have additional cells and collagen, a protein important for skin structure. Keloids might appear after an injury or just develop spontaneously. They are often seen on body parts like earlobes, shoulders, chest, back, cheeks, and knees, and are more common in individuals with darker skin. They might be painful or itchy and usually start to show about three months after an injury. Unlike most scars, keloids keep growing rather than improving and often recur even after attempted removal. Here’s an easy way to identify a keloid: it extends beyond the original scar borders.
On the other hand, hypertrophic scars are more common than keloids. Unlike keloids, hypertrophic scars don’t overgrow the original wound’s borders, and they aren’t majorly influenced by genetics. They can appear on all skin tones, but are often seen on the sections of the body where the skin is tight. They usually appear within a month of the injury and start to fade away after around six months. Another good news about hypertrophic scars is that they are less likely to return after being removed, which makes handling them easier compared to keloids.
Testing for Hypertrophic Scarring Keloids
If your doctor suspects you might have a keloid or hypertrophic scar, they will start by asking about your medical history. They will want to know if there’s been any trauma or injury to the area. Hypertrophic scars usually only form after an injury. If there was an injury, the scar could either be hypertrophic or a keloid. Your doctor will also ask about any pain or itchiness, as these symptoms are more common with keloids. There might be a higher risk of developing keloids if other family members have had them, so the doctor will ask about your family history too. Information about how long the scar has been there and if it has changed in size can help your doctor identify the type of scar. If the scar seems to be getting smaller over time, it’s likely a hypertrophic scar since keloids don’t usually get smaller by themselves.
During the physical examination, the doctor will see where the scar is. Keloids are more common on the earlobes, face, chest, and back, while hypertrophic scars usually show up on surfaces of the body that extend, like elbows and knees. The color of your skin can also provide clues, with keloids being common in people with darker skin tones and hypertrophic scars can occur in all skin types. Keloids tend to expand beyond the original injury site and can sometimes appear without any known injury, whereas hypertrophic scars don’t tend to spread beyond the injury site.
Your doctor might also send a small sample of the scar tissue for lab testing to help confirm the diagnosis. Lab technicians will check for the pattern of collagen – the main structural protein in skin – in the scar. Hypertrophic scars have collagen that aligns in a more parallel pattern whereas in keloids, the collagen shows a random swirling pattern. Hypertrophic scars will also consist of thin collagen fibers with a greater amount of collagen type III to type I, and keloids will have thick collagen type I fibers. In addition, hypertrophic scars will contain cells called myofibroblasts and a protein called alpha-smooth muscle actin that are not found in keloids.
Treatment Options for Hypertrophic Scarring Keloids
Treating thick and raised scars (hypertrophic scars and keloids) can be tough, and there are various options to choose from. The top rule when it comes to scarring is preventing it by keeping away from injuries. However, if these injuries are inevitable, it’s crucial to use preventive therapies like topical treatments during the healing process to prevent the formation of abnormal scars. For patients who already have an injury that has formed a keloid or a hypertrophic scar, medical help becomes essential to help alleviate any pain or itching, and to improve the look of the scar.
The primary treatment options for keloids and hypertrophic scars include occlusive dressings, compression therapy, and steroids. An occlusive dressing is a type of bandage that covers the scar, thought to work by reducing the production of collagen, a protein responsible for the skin’s strength and structure, by limiting the delivery of blood, oxygen, and nutrients to the scar. Patients need to wear these dressings almost the entire day, and they work best just after an injury or surgery. Compression therapy is another treatment option that applies pressure to the affected area, which thins the skin and reduces the stickiness of collagen fibres. Some examples of compression therapy are pressure earrings and elastic bandages. Steroids are also used because they decrease the production of collagen and inflammation-causing substances. Steroids can be injected into the scar tissue every four to six weeks over several months, either alone or in combination with other treatments.
Surgical treatment involves removing the scar and then closing the wound, making sure to do so without any strain to minimize the chance of the scar coming back. While there is a high chance that keloids may return after surgery, this can be reduced when combined with other treatments such as steroids, radiotherapy (use of high-energy radiation), and interferon therapy (which boosts the immune system to fight diseases). Cryosurgery, which uses extremely cold temperatures to damage cells and cause them to die, can also help reduce the size of the scar. This is more effective on smaller scars and is found to be more successful in reducing hypertrophic scars than keloids.
Radiation therapy, which uses high-energy radiation, can be used in combination with surgical removal in cases of recurrent keloids. It is usually used the day after the scar has been surgically removed. While it is effective, one of the downsides is the potential risk of getting cancer from the radiation, even though the dose of radiation is low.
There are also newer and emerging therapies that include interferon, 5-fluorouracil, imiquimod, tacrolimus, bleomycin, retinoid acid, and botulinum toxin A. These medications work by either reducing collagen production, preventing the growth of fibroblasts (cells that produce collagen), inducing cell death in scar tissue, reducing inflammation, or reducing tension on the healing wound (tension can lead to the formation of keloids and hypertrophic scars). All these methods help improve the appearance of scars.
What else can Hypertrophic Scarring Keloids be?
There are several serious conditions that can look like keloids (raised scars) or hypertrophic scarring (thickened, wide, often raised scars). These include malignant dermatofibrosarcoma protuberans, a type of skin cancer that can be identified under a microscope by a specific pattern of cells and a range of proteins that aren’t present in keloids or hypertrophic scars.
Trichilemmal carcinoma, a rare, hair follicle-related skin cancer, can also look like a keloid. These are diagnosed by identifying large, shiny keratin cells. Keloidal basal cell carcinoma, another type of skin cancer, can be confused with keloids due to the presence of thick collagen bundles. It’s vital to differentiate these cancers from keloids or hypertrophic scars because steroids, a common treatment for keloids and hypertrophic scars, should not be used to treat malignant tumors. In fact, they once misdiagnosed a 9-year-old’s malignant tumor as a keloid!
A skin condition called cutaneous scleroderma can also resemble keloids or hypertrophic scars. This condition is characterized by thickened skin and darkened keloid-like lesions. If a doctor suspects scleroderma, they should consider a skin biopsy. On microscopic examination, the collagen bundles in scleroderma are arranged differently than other scar tissues.
Similarly, sclerotic neurofibroma, a type of noncancerous (benign) nerve tumor, can be mistaken for a keloid, but testing will show the presence of a specific protein called S100. One more condition to add to the list – infections like hair folliculitis (inflammation of a hair follicle) can look like a keloid too. It’s important to distinguish this infection because, as in the case of malignant tumors, steroids should not be used to treat infections.
What to expect with Hypertrophic Scarring Keloids
Hypertrophic scars, which are thick scars that develop after an injury, tend to have a better outlook compared to a type of scar known as keloids. These scars typically form shortly after the injury and may grow for some time before they begin to reduce in size on their own. They are more responsive to treatment, usually only needing one type of treatment, and are less likely to appear again.
On the other hand, keloids, which are raised scars that expand beyond the original injury site, have a less favorable outlook. they are often related to your genes, meaning people at risk can develop multiple keloids after surgeries or injuries. Keloids can continue to grow for up to a year and do not reduce in size on their own. After being treated, often with surgery, keloids are more likely to reappear, which makes treating them challenging. Therefore, additional treatments are often used after surgery to help prevent keloids from returning.
Possible Complications When Diagnosed with Hypertrophic Scarring Keloids
Keloids and hypertrophic scars cause a lot of discomfort, including prolonged pain and itching. They can also be unsightly and can affect your movement, depending on their location and size. These types of scars can contribute to emotional and psychological stress because of how they look and feel. There are several treatments available to help with these issues, but there’s no one-size-fits-all solution, and each treatment comes with its own set of side effects.
The most common issues with keloids and hypertrophic scars are itching, followed by pain, and depending on where the scar is located and the size, it can limit a person’s movement. There’s also substantial evidence supporting the emotional and psychological impact of having a scar.
It’s essential to remember that while some treatments help manage these scars, none are without risks. No matter the treatment you opt for, there’s a chance of the keloids or hypertrophic scars recurring. The highest chance of recurrence is after surgical removal of the keloids. Here are the associated risks of some common treatments:
- Steroids: There’s the risk of spider veins, skin thinning, and color changes around the area being treated.
- Cryosurgery: This treatment often causes the area to lose its original color and could lead to blisters and pain.
- Radiation therapy: While there’s a risk of developing cancer after this treatment, no cases have been reported for treating keloids and hypertrophic scars with radiation therapy.
Preventing Hypertrophic Scarring Keloids
It’s important for patients to understand the risks factors of two types of unusual scars: keloids and hypertrophic scars. These are distinct types of scars that can form after any injury or surgery. While we often see scars as simply a visual mark, keloids and hypertrophic scars can cause discomfort and itchiness, and, in extreme cases, even disrupt normal body functions, which is why may require special attention.
Before any surgical procedure, doctors should talk to those who are at a higher risk of developing these scars, about ways to prevent them and alternative ways to manage them, should they occur. Even though there are several treatment options available, there isn’t a one-size-fits-all solution that works for everyone to prevent or treat these scars. This is particularly the case with keloids, which have a high chance of coming back even after treatment.
Therefore, if you have a history of developing keloids or hypertrophic scars after an injury or surgery, it’s crucial to work closely with a skin specialist, or dermatologist. The doctor can create a personalized plan for you to manage these scars, in order to prevent them from growing larger and potentially interfering with your body’s normal functions.
