Psoriasis is a chronic skin condition that causes skin cells to grow abnormally and faster than unusual. In the presence of the condition, cells form thickened patches of reddish lesions that can also appear white or silver.
Though commonly found on the scalp, elbows and knees, the lesions may develop anywhere on the body. Of the people diagnosed with the skin problem, 10 to 30% may progress to psoriatic arthritis (PSA) years later. PSA may develop at any time, but the condition remains most prevalent in people between 30 and 50 years of age. Researchers have not determined a specific cause, but they believe genetics and immune system irregularities are major factors.
This form of arthritis typically produces inflammation in the joints of the hands, feet, knees, and ankles. Usually, not all the joints are affected simultaneously. Some patients experience the inflammation in symmetrical joints, which is similar to rheumatoid arthritis. In general, symptoms are worst in the morning. The affected areas swell, feel warm to the touch, appear reddened, and are painful. When occurring in the fingers or toes, the entire digit may swell. In rare instances, patients may suffer from the “mutilans” form of the disorder. In this instance, the arthritis damages the hand and feet joints, causing function loss. In 80% of cases, the fingernails may appear pitted and ridged.
People with PSA may also develop spinal inflammation, which causes pain and stiffness in the neck, upper back, lower back, and buttocks. Some patients endure inflammation of the cartilage, ligaments, and tendons around joints, which leads to a condition known as enthesopathy. When occurring in the heel, the condition is referred to as Achilles tendinitis and causes painful walking and difficulty with movements requiring extension and flexion of the Achilles tendon.
When the inflammation occurs in the chest wall, people may experience chest pain and difficulty breathing. The condition may also affect various organs throughout the body including the heart, kidneys, or lungs. PSA of the eyes irritates the iris and is known as iritis. Bright lights worsen the discomfort and corticosteroid injections may become necessary to prevent blindness. When inflammation of the aorta occurs, the heart valves may become inflamed, weakened, and leak, which may cause shortness of breath and potential heart failure.
When to Consult a Physician
People usually see a healthcare provider for ongoing treatment and monitoring of symptoms when psoriasis lesions appear. However, people diagnosed with psoriasis should make a point of consulting a physician if they experience unusual sensations in their joints, eyes, or other regions of the body. In 15% of patients, PSA may precede any skin lesions, and a positive diagnosis often occurs after individuals reveal that a family member has psoriasis. Testing rules out the possibility that symptoms are related to other types of arthritis or autoimmune disorders.