At first glance, psoriasis and eczema are easily mistaken for one another because they share several similarities. However, it is vital that each skin condition is accurately diagnosed to determine the best course of treatment. Here is a guide prepared by our dermatological team to help you differentiate these conditions.
What is Eczema?
Eczema is an umbrella term for a group of inflammatory conditions that weaken your skin, causing a host of complications, including dryness, itching, rashes, and scaly or crusty skin. An eczema flare can last for several days or weeks, often triggered by environmental factors. In more chronic cases, an eczema flare may require medical attention to address complications, such as skin infections. While there is no cure, eczema is not contagious and can be managed with various treatments to control symptoms and prevent or alleviate flares.
Eczema’s primary cause is still unknown, but it is believed that an overactive or disrupted immune system overreacts to environmental triggers. Triggers may include anything from dust and certain fabrics to pet dander, pollen, and even weather changes. In response, the immune system triggers inflammation to clear these irritants, but excessive inflammation can gradually lead to eczema symptoms. Other causes include genetics (as eczema may be hereditary), secondary conditions that weaken the skin barrier, stress, or a combination of factors.
Eczema’s appearance may differ by skin tone: lighter skin tones may show pink or reddish bumps or rashes, while darker skin tones may show dark brown, grey, or purple patches with small, dry bumps. Eczema’s appearance may also change based on how long you have been experiencing symptoms.
What is Psoriasis?
Psoriasis is a chronic inflammatory skin disease that causes well-defined patches of thick, scaly, discoloured skin called plaques. Plaques are typically reddish, with silvery scales atop the redness. An overactive immune system causes excessive inflammation that accelerates skin cell growth, causing skin cells to accumulate on your skin’s surface and create these plaques. There is currently no known cure for psoriasis, but symptoms can be managed through various medical treatments. Like eczema, psoriasis is not contagious.
The formation of these plaques also leads to other symptoms, such as itchiness, dryness, pain, and cracking in the areas where they grow. The plaques may appear to be red, pink, violet, or brown, depending on your skin tone. Scratching the plaques is not advised, as it can tear the scales off your skin, cause bleeding, and increase the risk of infection.
The exact cause of psoriasis is still unknown, but it may also stem from potential causal factors such as genetics. The condition is also triggered by environmental irritants or allergens, and those predisposed to psoriasis may remain symptom-free until a trigger occurs. There may also be instances in which psoriasis is mistaken for other conditions with similar symptoms, such as eczema or ringworm.
Key Differences Between Psoriasis and Eczema
Despite sharing several potential causal factors and symptoms, psoriasis and eczema are very distinct conditions. The differences are generally more noticeable to dermatologists and other medical professionals, but many individuals may find it difficult to tell them apart due to their overlapping similarities. Here is how each skin condition differs.
General Appearance
Eczema causes a thin, dry, scaly rash with discolouration that varies depending on your skin tone. Eczema rashes may also appear less defined, appearing as randomly shaped patches on your skin. In rarer cases, you may also notice small bumps or fluid-filled sacs present.
In contrast, psoriasis presents well-defined, discoloured plaques with thick and raised silvery scales that cover a significant area of your skin. “Well-defined” here typically means that there is a noticeable border outlining the plaques. The thicker, raised appearance of a psoriasis patch is due to the excess formation of skin cells that outpace your body’s natural ability to shed them.
Symptoms & Intensity
While both eczema and psoriasis cause dry, itchy skin, eczema’s itch is generally considered to be quite intense. In some cases, eczema causes a more severe itch than psoriasis, which can lead to further skin irritation. Constantly scratching the affected area can eventually cause bleeding. In comparison, psoriasis has a burning or stinging sensation accompanied by pain, discomfort, and flaking skin, though you may experience less of an itch compared to eczema.
Location
Eczema typically forms around areas where the skin may fold, such as your neck, wrists, inner elbow, ankles, or behind your knees. Meanwhile, psoriasis tends to form on your elbows, knees, scalp, lower back, the palms of your hands, and the bottoms of your feet. However, there may be instances where eczema or psoriasis may affect other areas as well.
When The Condition Starts
While both conditions can start at any time, eczema is more likely to occur during childhood. Eczema is also more prevalent than psoriasis. Childhood eczema may show gradual improvement as a child gets older, while psoriasis tends to be a lifelong condition that starts between ages 15 and 35.
Underlying Causes
Though their actual causes are still being studied, psoriasis primarily involves the overactivity of T-cells, a type of white blood cell, in the immune system. In individuals with psoriasis, the T-cells mistakenly attack healthy skin cells instead of protecting the body, leading to significant inflammation and the beginning of psoriasis symptoms. This immune response can occur due to factors like stress, certain medications, or infections.
Eczema arises from genetic and environmental factors, in which defects in skin barrier function prevent the skin from being protected. This makes your skin more susceptible to infections and various environmental triggers, such as allergens and temperature changes. Those with a family history of allergic conditions may find themselves at higher risk of eczema.
How to Tell If You Have Psoriasis or Eczema
It is never easy to tell whether you have psoriasis or eczema, as they can still be mistaken for one another based on initial observations. Though uncommon, it is also possible for a person to develop both eczema and psoriasis simultaneously. There is also the risk of atypical presentations of psoriasis and eczema, which could complicate treatment if not accurately diagnosed.
To avoid unpleasant side effects, it is wise to seek professional medical advice to properly determine which condition you have, ensuring you receive the right treatment to manage symptoms effectively. If you need support for either psoriasis or eczema, or are unsure which condition you may have, visit Stratum Skin and Surgery to consult with our dermatological team.