Juvenile Arthritis-Related Skin Symptoms Vary

Updated by Linda Rath | June 10, 2024

Children get many of the same types of arthritis adults do, and they can be just as hard to diagnose. That’s especially true for children of color because the rash that marks many forms of juvenile arthritis often looks different on darker skin, and so may go unnoticed and untreated. 

This compounds the medical inequities that many people of color in the U.S. already experience as a result of long-standing systemic biases. Research has found time and again that Black, Hispanic and Native people with rheumatic diseases are less likely to receive a timely diagnosis and high-quality care than white patients are. Clinical trials largely have a majority of white participants, and a shortage in the rheumatology workforce is exacerbated by a lack of diversity, which also lends in inequitable care. And medical teaching materials typically focus on white people.

Angela Chun, MD, a pediatric rheumatologist at Northwestern University’s Lurie Children’s Hospital and an Arthritis Foundation diversity, equity and inclusion (DEI) grantee, is working to change that. She’s developing training modules to help providers identify rashes on different skin types, because the images used in medical classes and textbooks have historically shown only lighter skin.

“In pediatric rheumatology, laboratory tests and imaging can help support a diagnosis, but we still rely heavily on a thorough history and physical exam to raise our suspicions for rare rheumatic diseases. Recognizing rashes can therefore be a crucial key to diagnosis, especially if the rash looks different from the images in medical textbooks,” she says.

Arthritis-related skin rashes

Hundreds of things can cause a skin rash, including allergies, infections and medications. But certain rashes are specific to juvenile arthritis. Here’s what to know about rheumatic rashes and how they appear in different races and ethnicities.

Systemic juvenile idiopathic arthritis (sJIA). Systemic JIA is a serious subtype of juvenile arthritis that can affect the liver, lungs and heart as well as joints. It can be more challenging to diagnose and treat than other types of childhood arthritis and even more so in children of color.

One of the first signs of sJIA may be a high daily fever, usually spiking in the evening, accompanied by a rash that comes and goes with the fever. Although a fever that rises in the evening and then returns to normal is one of the diagnostic criteria for sJIA, studies have shown that the fever can occur in the morning or even last all day. What’s important is that it almost always occurs with a rash. In light skin, the rash is usually salmon-pink and slightly raised, but the pink color can be hard to see on darker skin. It can show up anywhere, including the trunk, face, palms of the hands and soles of the feet. The rash is also fleeting, sometimes clearing up without a trace within a few hours as the fever subsides. A rash without fever, especially if it has blisters or is any color other than pink, is likely not a sign of sJIA, Dr. Chun says.

Juvenile psoriatic arthritis (PsA). This type of arthritis develops in about one-third of adults and kids who have the skin disease psoriasis. On white skin, psoriasis is a dry, red rash covered with silvery scales. Hispanics have the same silvery scale but the rash is salmon-colored. On Black skin, psoriasis looks purplish brown with thick gray scales and is often confused with other skin conditions, including eczema. Patients of color are not only frequently misdiagnosed but generally wait much longer for a diagnosis than white patients.

Psoriasis plaques can be found along the hairline, behind the ears, near the belly button and over the elbows and knees. Psoriasis can also cause crumbling, pitted nails. Scalp and nail psoriasis are more common, severe and harder to treat in Black patients. In general, Black children have more severe psoriasis over more of their bodies than white kids do, although psoriasis is far more common in whites. Children and adults of color also more likely to develop hypopigmentation (loss of skin color) or hyperpigmentation (darker skin color) where psoriasis plaques have healed. These skin changes aren’t permanent but can take a long time to go away. 

Juvenile dermatomyositis (JDM). Juvenile dermatomyositis is a rare autoimmune disease marked by muscle weakness and distinctive skin rashes. These rashes are purple or red in lighter skin but may be missed in darker skin until they’ve healed, leaving behind post-inflammatory hypo- or hyperpigmentation. Knowing where look for different rashes and their typical appearance is key. Dr. Chun breaks it down this way:
•    Heliotrope rash (purple) around the eyes
•    Gottron papules (red) over the knuckles
•    Extensor erythema (red) over knees and elbows
•    V-neck sign (red) on sun-exposed parts of the neck and chest
•    Shawl sign (red or purplish) on the tops of the shoulders
•    Holster sign (violet) on the sides of the hips

Dr. Chun says doctors should “pay special attention to the blood vessels under the nail cuticles, which can become dilated and [twisted].” These blood vessels may be harder to see on darker skin, so doctors may use a dermatoscope — a magnifying tool with a light — or even a cell phone light to see the blood vessels under the nails.

Pediatric lupus erythematosus (lupus, SLE). Lupus is an autoimmune disease that mainly affects young Black, Hispanic, Asian and Native women and teens. It’s less common but more severe in children and more likely to seriously damage their kidneys and central nervous system. Adult Black women with lupus are also more likely to have severe kidney damage.

About half of lupus patients have a distinctive malar or butterfly-shaped rash that stretches across the bridge of the nose to both cheeks. In light skin, the rash is red or pink, but it may look brown on darker skin or not be noticeable until the hyper- or hypopigmentation stage. One way to distinguish it, apart from its characteristic shape, is that it doesn’t extend to the space under the nostrils. Many kids and adults with lupus are sensitive to the sun and fluorescent light, which can trigger sunburn and skin rashes as well as lupus flares. Strong sun protection for anyone with lupus is essential.

Juvenile (localized) scleroderma. Juvenile scleroderma is an autoimmune disease affecting both adults and children in which connective tissue cells produce too much collagen, the structural protein that supports most of the body, including the skin and blood vessels. The excess collagen builds up, causing parts of the skin to become hard and tight. 

There are two types of scleroderma: localized, which affects only the skin and underlying tissues, and systemic scleroderma, also called systemic sclerosis, which can affect the whole body. Localized scleroderma is much more common in kids and teens, and rarely becomes systemic. 

Symptoms of localized scleroderma range from small reddish spots that resemble birthmarks to round lesions or lines on the legs, arms and face. Dr. Chun describes the affected skin as initially looking “red or purplish, almost like a bruise but over time becoming indented and waxy like a scar.” She points out that red or purple discoloration is hard to see on darker skin. Even on lighter skin, localized scleroderma can be hard to spot because the early signs are subtle. It may take months or years to get a correct diagnosis — even longer for Black children. 

According to recent research, more Black children than previously thought have systemic sclerosis, which can damage the digestive tract, kidneys, lungs and heart. Systemic sclerosis has the highest mortality rate of any systemic autoimmune disease.

The first symptom of systemic sclerosis is Raynaud’s phenomenon, which occurs when cold weather or stress restricts circulation in the fingers and toes. This can lead to numbness, tingling and skin color that changes from white to blue or purple and then to red as circulation returns. In light skin, the color changes are obvious, but in dark skin, only the white phase may be noticeable. Dr. Chun points out that Raynaud’s is quite common in otherwise healthy people, especially teen girls. Examining the blood vessels in the nail folds may help identify a more serious illness. Still, the difficulty in seeing the full range of Raynaud’s symptoms and the belief that systemic sclerosis is rare in kids makes an accurate diagnosis as challenging as it is imperative in children of color. 

Vasculitis. This group of diseases causes inflammation of the blood vessels. Different types of vasculitis are classified according to the size of the blood vessels they affect. For example, leaking blood from inflamed small blood vessels like capillaries can cause red, purple or brown spots, called “petechiae,” or larger red patches known as “purpura.” Almost everyone with vasculitis will have one of these rashes. As with other skin disorders, vasculitis may be less visible in dark skin, and red inflammation may appear purplish or dark brown.

The most common types of acute vasculitis in children are IgA vasculitis (formerly called Henoch Schoenlein purpura) and Kawasaki disease. Dr. Chun says IgA vasculitis is “associated with petechiae and purpura, especially in the legs; joint pain; abdominal pain and kidney problems.” She says Kawasaki disease can cause a persistent fever, red eyes, swollen lymph nodes, chapped lips and swelling of their hands and feet.

When vasculitis is suspected in patients of any race or ethnicity, dermatologists usually perform a biopsy to help with the diagnosis.