When it comes to describing the symptoms of psoriasis, most people think about the red, scaly rash associated with plaque psoriasis, the most common form of the disease. But there are other types of psoriasis, each with its own characteristic signs and symptoms. In addition, certain forms of the autoimmune disease can easily be mistaken for other conditions and, as such, require expert evaluation to reach the correct diagnosis.
The symptoms of psoriasis are directly linked to the type of disease involved. While dermatological (skin) symptoms are common, they can vary in appearance and may not even occur in some cases. In fact, some types of psoriasis are limited to the nails, joints, or specific parts of the body.
Psoriasis symptoms will develop in acute episodes called flares. The flares are typically spurred by a “trigger” such as stress, medications, or a skin injury. Other events are idiopathic (of unknown origin), developing suddenly and resolving just as quickly. Even if psoriasis symptoms are persistent, there will be episodes in which the condition will suddenly worse and improve.
6 types of Psoriasis:
1. Plaque Psoriasis
Plaque psoriasis accounts for around 80% of all cases and is considered the “classic” form of the disease. Plaque psoriasis is defined by:
- The appearance of superficial red patches of skin covered with white to silvery scales
The patches can appear anywhere on the body but are most common on flexor surfaces (areas of skin opposite a joint, such as the inside of an elbow or the back of a knee). The rash also can show up on the scalp, face, and around or inside the ears. The reddened plaques will sometimes consolidate and cover greater portions of the body.
Although the scales on the surface of skin tend to shed easily, the ones just below are more tenacious and can bleed easily if scratched. This can lead to a classic finding called the Auspitz sign in which the tiny pinpoints of bleeding create a pattern similar to scabies.
When plaque psoriasis affects the scalp, it can easily be mistaken for dandruff (seborrheic dermatitis). However, with psoriasis, the affected skin will be dry with a silvery sheen; with seborrheic dermatitis, the skin will almost always be oily. Psoriasis on the scalp may be mild, with small patches on the back of the head and neck, or generalized, affecting the whole head.
When occurring on the face, psoriasis may affect the eyebrows, upper lip, and hairline. Very rarely, psoriasis can develop on the gums or inside the nose, cheeks, or lips. These lesions are often whitish or grey and can interfere with chewing and swallowing. While similar to aphthous ulcers, psoriatic lesions tend not to have a consolidated center.
Psoriasis in the ear can be problematic as the flakes can gradually accumulate inside the ear canal. Symptoms may include pain, itching, ear wax blockage, and hearing loss.
2. Nail Psoriasis
More than 50% of people with skin psoriasis also have nail psoriasis, characterized by the overproduction of keratinocytes in the nail matrix. On the flip side, 5% of people with nail psoriasis will not have any signs of skin psoriasis, according to the National Psoriasis Foundation (NPF).
The symptoms of nail psoriasis are similar to other nail diseases, including onychomycosis (nail fungus). They include:
- Pitting (small dents or pits on the surface of the nail plate)
- Distal onycholysis (lifting of the nail from the nail bed)
- “Oil drops” (a translucent, yellow-red discoloration in the nail bed)
- Subungual hyperkeratosis (thickening and scaling of the nail)
- Leukonychia (white patches on the nail plate)
At its worst, nail psoriasis can cause the nail to become thick, crumbly, and unsightly. This may not only cause embarrassment but interfere with a person’s ability to walk.
3. Guttate Psoriasis
Bumps resulting from a guttate psoriasis rash can be described as:
The rash can appear suddenly on the torso, arms, or legs, usually following a viral or bacterial infection like strep throat, chickenpox, or the common cold. It is more common in children given that they are more prone to these infections.
4. Inverse Psoriasis
Inverse psoriasis, also known as intertriginous psoriasis, is a relatively rare form of the disease affecting skin folds. Inverse psoriasis typically occurs behind the ears, under the breasts, between the buttocks, or in the groin or armpits.
Because these areas tend to be moist, the patches won’t be scaly. Rather, skin affected by inverse psoriasis appears:
5. Pustular Psoriasis
As the name suggests, pustular psoriasis is characterized by pus-filled lesions rather than scaly plaques. The pus, composed of dead white blood cells and lymph fluid, isn’t contagious.
There are several subtypes of pustular psoriasis. In the focal form of the disease, the rash appears only on small areas of the body, such as the palms, soles, fingers, or toes.
Von Zombusch psoriasis is a more serious form that can cover large areas of skin. It usually starts with generalized redness and tenderness, after which white pustules appear in flexural areas of skin (such as the backs of the knees or the inside of the elbows, armpits, or groin).
Other symptoms of Von Zomzusch psoriasis include fever, chills, dehydration, rapid heart rate, fatigue, weight loss, and muscle weakness. If left untreated, the disease can spread to the bloodstream and become fatal.
6. Erythrodermic Psoriasis
Erythrodermic psoriasis is a rare and severe form of the disease characterized by the massive shedding of skin from all over the body. Rather than smaller scales, the skin will come off in large sheets. Erythrodermic psoriasis often looks similar to a severe burn or a drug-induced case of Stevens-Johnson syndrome (SJS) or toxic epidermal necrosis (TEN).
Erythrodermic psoriasis can also cause:
- Severe itching and pain
- Tachycardia (abnormally rapid heart rate)
- Fluctuations in body temperature
If left untreated, erythrodermic psoriasis can be life-threatening, leading to severe infections (such as sepsis or pneumonia) or congestive heart failure.
Beyond its effect on the skin and nails, psoriasis may directly or indirectly affect other organ systems, most specifically the eyes and joints.
Psoriasis can cause eye problems, as the scaling and dryness around the eyes can cause the eyelids to curl up unnaturally. This can lead to eye dryness, redness, itchiness, and blurring. The altered shape of the eyelid can also cause the eyelashes to scrape against the cornea (the fluid-filled layer at the front of the eye).
Psoriasis is also associated with uveitis (inflammation of the middle layer of the eye), the symptoms of which include:
- Conjunctivitis (pink eye)
- Sensitivity to light
- Eye pain
- Blurred vision
- Floaters (floating spots in the field of vision)
People with psoriasis are more likely to have recurrent bouts of uveitis than those without. This places them at greater risk of eye damage and vision loss, particularly in severe cases where psoriasis flares are frequent.
With psoriatic arthritis, the characteristic skin rash is accompanied by inflammation of the joints. As with other types of psoriasis, psoriatic arthritis can cause joints to enlarge and become misshapen over time. Uveitis and nail arthritis may also co-occur.
Psoriatic arthritis is different from osteoarthritis (“wear-and-tear” arthritis) in that it can affect connective tissues as well as the joints themselves. Unlike rheumatoid arthritis, in which the same joints on both sides of the body are typically affected, psoriatic arthritis may develop symmetrically or asymmetrically, often in tandem with other skin and nail symptoms.