Psoriasis is a skin condition that affects around 2% of the population. Although you can develop the condition at any age it is most common to start in those under 35. Psoriasis affects both men and women equally and its severity will differ greatly from person to person.
Psoriasis presents as red, inflamed and crusty looking patches which often have white scales overlying. It is most likely to appear on the elbows, knees, back and scalp but can appear anywhere on the body. For some, psoriasis is a minor irritation but for others it can have a huge impact on their day to day life becoming painful, itchy and unsightly.
Those with the condition can often find that the go through periods of remission where the skin will improve. Likewise, the symptoms can become more severe and may require more extensive treatment than may have been previously applied.
Why Does Psoriasis Occur?
The normal skin production cycle, where skin cells are made and replaced usually takes around 3 to 4 weeks in healthy skin however this is accelerated in those with psoriasis resulting in the process only lasting around 3 to 7 days. As the skin which is made is not mature enough or ready to shed it builds up in plaques on the skin resulting in the patches associated with psoriasis.
Although it is not known why this occurs, it is thought to be linked to the immune system attacking the bodies own healthy skin cells. The immune system includes T-cells. These cells travel through the body to detect and fight bacteria and other germs. In those with psoriasis, for some unknown reason, they start to attack the healthy skin cells. This then causes the deepest layer of skin to produce new skin cells much quicker that normal which in turn triggers the production and release of more T-cells.
The condition is not contagious and therefore cannot be caught or passed from person to person but there is some evidence that it is genetically linked therefore it may be more common within families. It is also thought that the condition can lie dormant until there is a trigger which causes the process to start. These are thought to include stress, injury to the skin, throat infections and using certain medicines. Those who smoke or drink excessive amounts of alcohol are also more likely to have psoriasis as well as women going through hormonal changes such as puberty or menopause.
How is Psoriasis Diagnosed and Treated?
Most GP's or dermatologists will be able to diagnose psoriasis by assessing the lesions but a skin biopsy is required to make a definitive diagnosis to rule out other skin complaints such as fungal infections and dermatitis.
There is no cure for psoriasis but there are several treatments which improve the skin and help with symptoms.
• Topical treatments – this includes creams and ointments which are applied directly to the skin. These can often include steroid creams which reduce inflammation in the lesions.
• Photo Therapy – the skin is exposed to certain types of ultraviolet (UV) light in a controlled environment.
• Systemic therapy – Oral medication or injections are given to help work throughout the entire body. This is often used in only severe cases.
• A combination of any of the above used together may allow a more successful treatment.
Associated Conditions Which Can Affect the Feet:
There are a number of conditions associated with psoriasis. Two of the most common are psoriatic nails and psoriatic arthritis.
This condition occurs in around half of those who develop psoriasis and can affect the fingers and toenails, most however are only mildly affected. The nails are made of the same protein, keratin, as skin and therefore can also be affected by psoriasis. The severity of the skin does not always determine whether or not the nails will be affected. It is unknown as to why some people develop nail involvement where others do not.
Changes which can occur in the nail with psoriatic nails:
• Pitting - where the nail develops tiny indentations like the surface of a thimble. There can be one indentations or dozens.
• Onycholysis – the nail becomes detached from the nail bed causing lifting. This can rage from mild where the end of the nail will turn white or yellow to full loss of the nail plate. This is often mistaken for fungal infections but as the nail plate is detached leaving a gap ideal for bacteria, infections can often develop and therefore go untreated.
• Subungal Hyperkeratosis – where the nail thickens and can become discoloured. As the nail increases in thickness this can be particularly uncomfortable in the feet as footwear can cause pressure.
Treatment for psoriatic nails is thought to be one of the most difficult associated with psoriasis. Ensuring regular routine footcare by a podiatrist which will ensure any bulky nails are reduced and risk of bacterial or fungal infections are kept to a minimum. There is some evidence to believe that rubbing steriod creams into the cuticle can be beneficial although the results can be inconsistent and there is risk that the skin at the cuticle can become thin and fragile.
Psoriatic arthritis causes painful inflammation within the joints in around 1 in 5 of those who have psoriasis. Although it can affect any age it is less common in children and teenagers. Like psoriasis it is unclear why psoriatic arthritis develops or why only some develop it but it is thought to be also linked to the immune system.
Treatments for psoriatic arthritis can vary but the most common treatment is anti-inflammatory drugs to relieve inflammation, swelling and pain. In most cases medication known as non-steroidal anti-inflammatory drugs (NSAIDs) are used at first. In more severe cases or when NSAIDs are not affective an oral steroid or injection may be used. Drugs known as disease modifying anti-rheumatic drugs (DMARDs) can also be used to tackle the underlying cause of inflammation in the joint.
When affecting the feet, it is essential that shoes are not too tight. As the joints can become swollen the foot may become wider or deeper than before. Pressure to any prominences can result in corns, callous or breakdown of tissue resulting in pressure sores. Breaks in the skin as well as comprised immune system can also increase the risk of infection therefore any areas must be kept clean and covered. Regular care by your podiatrist can help to reduce some of these complications.