What is Nail Psoriasis?
Psoriasis is a lasting skin condition that causes inflammation, but it can also affect other parts of the body. For instance, some people experience psoriasis symptoms on their nails, all over their body, or both. Sometimes, the first sign of psoriasis is in the nails. This can happen before skin symptoms appear, as a result of the skin condition later on, or along with other skin symptoms.
Psoriasis affects the nail bed or nail matrix, which is reportedly what causes nail psoriasis. A sign of nail psoriasis might be inflammation in the joints, especially in the small joints of your fingers, where psoriasis-related arthritis typically appears.
When psoriasis affects the nails, it can look different for different people. Examples of these differences include changes in the color of the nails, thickening beneath the nail, tiny dents in the nail surface, and detachment of the nail from the nail bed. These changes depend on which part of the nail psoriasis is affecting.
People who have psoriasis on their nails might not like how their nails look, which can affect their quality of life. In some severe cases, it can cause discomfort and make using the hands more difficult.
Managing psoriasis in the nails can be hard because it often requires long-term treatment, and it might not always control all of the symptoms. So, part of the treatment involves patient education. It’s important for patients to understand what to expect from treatment to help them prepare and increase the chances of successful treatment.
What Causes Nail Psoriasis?
The exact cause of nail psoriasis isn’t fully understood, but there are multiple factors that could play a part. These include genetic, immune system, and environmental factors. When nail psoriasis happens, inflammation (swelling and redness) occurs in the nail matrix or nail bed, which are the parts of your finger or toe responsible for nail growth.
Changes to the immune system, which is the body’s defense against illness and infection, is thought to be the strongest factor associated with nail psoriasis. There are also certain genes (like human leukocyte antigens Cw6, B13, B17) that are linked to nail psoriasis. If you have a family history of nail psoriasis, that suggests that it could be genetic or inherited. Despite this, we don’t fully understand these genetic links yet.
Risk Factors and Frequency for Nail Psoriasis
Nail psoriasis can affect anyone, regardless of age or gender, but it becomes more common as people get older. It is often associated with skin psoriasis and a type of arthritis known as psoriatic arthritis. In fact, a large percentage (80% to 90%) of individuals with psoriatic arthritis also have nail psoriasis. This is likely because psoriatic arthritis often affects the joint closest to the nail.
- Nail psoriasis is a condition that can affect anyone—children or adults; males or females equally. It becomes more common as people age.
- It is often seen alongside skin psoriasis and psoriatic arthritis.
- Studies demonstrate that 80% to 90% of people with psoriatic arthritis also have nail psoriasis. This is probably because psoriatic arthritis usually impacts the joint nearest to the nail.
- Nail psoriasis can appear by itself or at the same time as other psoriasis symptoms, or it may develop after skin symptoms have begun.
Signs and Symptoms of Nail Psoriasis
Patients with nail psoriasis often present with related skin changes and systemic issues such as psoriatic arthritis. That’s why, when examining a patient with nail psoriasis, doctors must conduct a comprehensive review of the symptoms and carry out a full physical examination.
The medical history should include the details of symptoms like:
- The time when symptoms were first noticed
- Which nails are affected
- How long the symptoms have lasted
- Any other noticeable patterns
- Any joint symptoms such as swelling or pain
- Smoking habits
- Medical history including heart disease, metabolic disorders, or psoriasis
- Family history of psoriasis
- Any recent infections
During the physical examination, doctors look for specific signs of nail psoriasis.
These findings can include:
- Pitting: Small dips on the surface of the nails
- Subungual hyperkeratosis: Building up of white keratin debris over the nail bed
- Onycholysis: Lifting of the nail plate from the nail bed
- Oil-drop discoloration: Appearing as red spots on the moon shape area of the nail or as pink spots or patches on other parts of the nail
- Nail crumbling: Breaking down of the distal part of the nail
- Leukonychia: White lines on the nail plate
- Splinter hemorrhages: Thin, red streaks on the nail
Though less common, other nail psoriasis signs like onychorrhexis, trachyonychia, and Beau lines may be seen. These changes can also occur with many other inflammatory or infectious conditions. Besides examining the nails, doctors often check the patient’s skin, with a focus on extensor surfaces, anal-genital area, and the scalp, where psoriasis typically manifests. Any affected joints should also be checked, for example, the distal interphalangeal joints. In certain cases, an ultrasound can provide more details about the joint and nail disease. With all these assessments, the extent of the disease can be gauged.
Testing for Nail Psoriasis
Nail psoriasis can be diagnosed by a doctor who conducts a detailed discussion with the patient about their symptoms and performs a physical examination. It’s crucial to rule out a fungal nail infection, as this can look very similar to nail psoriasis. To do so, a doctor may test a small clippings of the nail with different stains or grow a culture in a lab to confirm if fungus is present. However, keep in mind that having a fungal infection doesn’t mean you can’t also have nail psoriasis. So, after a fungal nail infection is treated, the doctor will check again to see if signs of nail psoriasis persist.
Although an ultrasound isn’t necessary, it might be used for some patients to support the diagnosis, yet this is still under research, especially for its effectiveness in diagnosing psoriatic arthritis, a type of arthritis that affects some people with psoriasis.
A nail biopsy (a sample of nail tissue for examination) is usually not needed. However, if the doctor is unsure about the diagnosis, they might take a sample from the nail matrix or nail bed. This is then examined under a microscope to look for signs of psoriasis.
Treatment Options for Nail Psoriasis
Nail psoriasis is a condition that can cause changes to your nails, such as discoloration, thickening, and pitting (small dents appearing on the surface). Depending on how severe or widespread this condition is, different treatments are recommended.
If you have mild nail psoriasis, which may mean just one or two nails are affected and you don’t have any other symptoms, doctors typically suggest topical treatments. These are medications that you apply directly to your nails. Commonly used ones include strong corticosteroids to reduce inflammation and creams containing vitamin D analogs, which slow the growth of skin cells. If these aren’t effective, other topical treatments, such as tacrolimus and tazarotene, may be considered. If these treatments are unsuccessful, injections of corticosteroids directly into the nail or medications that work throughout the body may be necessary.
If you have moderate-to-severe nail psoriasis, which involves more than two nails or includes other symptoms like joint pain, your doctor may recommend more systemic treatments. These are medications that work throughout your entire body and can include biologic drugs, which target specific parts of your immune system. Different types of biologic drugs include tumor necrosis factor inhibitors like adalimumab; interleukin-17 inhibitors like secukinumab, ixekizumab, and brodalumab; interleukin-23 inhibitors like guselkumab; and interleukin-12 and interleukin-23 inhibitors like ustekinumab. All these drugs have been found effective in managing nail psoriasis symptoms.
If nail psoriasis doesn’t improve with these treatments, or if these treatments aren’t suitable for some reason, other options could include methotrexate, apremilast, or pulsed dye laser treatment. It’s important to discuss the side effects and benefits of each treatment option with your doctor to decide on the best approach for you. Factors like your age, overall health, the extent of your nail psoriasis, and the cost of treatment can all influence this decision.
What else can Nail Psoriasis be?
Nail psoriasis can often be mistaken for other conditions that affect the nails. This is due to the fact that many other illnesses or situations can cause changes to the nails that look very similar to nail psoriasis. Some examples are:
- Age-related changes or trauma.
- Vascular diseases in the lower extremities, like peripheral artery disease or chronic venous stasis.
- Peripheral neuropathy, a nerve condition that can affect various parts of the body.
- Medications that can change the appearance of nails.
Despite these similar symptoms, other causes of nail changes would usually not show additional psoriasis symptoms. Below are some conditions that have very similar nail symptoms to nail psoriasis:
- Onychomycosis: This condition can make the nails look similar to those affected by nail psoriasis. Diagnosing onychomycosis requires a fungal culture or analyzing a nail clipping with specific preparations.
- Alopecia areata: This condition, which often causes hair loss, brings about a variety of nail changes. These can range from changes in nail texture to pitting and fissuring, among others.
- Lichen planus: This condition can make nails thinner and can create ridges and grooves on the nail surface. It can also lead to cuticle damage and the formation of a condition called pterygium. Lichen planus often also impacts the skin or mucus membranes.
- Pityriasis rubra pilaris: This condition can cause nails to thicken and lead to a condition called splinter hemorrhages. However, the skin symptoms of this disease can be quite similar to psoriasis.
Many other skin conditions, like atopic dermatitis, Darier disease, and Hailey-Hailey disease, can also cause nail symptoms that resemble those of nail psoriasis. These should also be considered when evaluating a patient with changes in their nails.
What to expect with Nail Psoriasis
People suffering from nail psoriasis experience long-lasting and recurring episodes of improvement and worsening. This can significantly affect their quality of life. Treating nail psoriasis can be more challenging, leading to less effective disease control. This is because there isn’t as much information about its treatment as there is for skin psoriasis.
The condition of nail psoriasis can get worse due to nail injuries, which are often hard to avoid. This is due to a process called “koebnerization”, which is the appearance of skin lesions on areas of the body that have experienced trauma or injury.
Despite these challenges, treatments involving topical (applied on the skin) or systemic (affecting the whole body) medications can help manage the disease. These treatments are often used for mild or moderate-to-severe cases of nail psoriasis. However, it’s worth noting that these treatments may come with some side effects.
Possible Complications When Diagnosed with Nail Psoriasis
Patients with nail psoriasis may experience some problems stemming from both the disease and the treatments for it. These problems can generally be grouped into three categories:
- Functional disability
- Psychological distress
- Infections
Functional disability relates to difficulties the patient might face in day-to-day activities because of their nail psoriasis. Psychological distress refers to the mental stress and anxiety the condition might cause. Infections include bacterial infections like paronychia, and fungal infections like onychomycosis.
Preventing Nail Psoriasis
Nail psoriasis is a long-term condition and treating it might take a substantial amount of time. Therefore, it’s crucial for those affected to understand what to expect. For instance, it’s worth noting that toenails take approximately 12 months, and fingernails nearly 6 months, to complete their growth cycle. This means that any changes to the nails, before and after treatment, will be slow to appear. To keep track of these changes, patients can take photographs of their nails over time.
It’s also important to look after the nails to avoid worsening the condition. This includes avoiding any injuries or damage to the nails, as this can trigger a reaction known as ‘koebnerization’, which can make the psoriasis worse. Wearing gloves when dealing with chemicals or moisture is advised, and people should always strive to keep their hands dry, with the exception of applying moisturizers.
Keeping one’s nails tidy, well-trimmed, and clean is also recommended, especially if nail detachment or ‘onycholysis’ occurs. This is because a detached nail can trap microorganisms, leading to infection. Even though people with psoriasis usually have a lower risk of infections compared to others, they need to be mindful about the possibility of getting an infection, especially a fungal nail infection known as ‘onychomycosis’.
