What triggers psoriasis, and why you shouldn't delay seeing a doctor
Psoriasis affects around 80 million people worldwide. It is a chronic, relapsing, inflammatory condition. It visibly affects the skin, but can also affect the nails and joints.
It is not infectious or contagious, but you should never delay seeing a specialist once the first symptoms appear. If left untreated, severe psoriasis can affect the function of other internal organs due to raised levels of inflammatory markers. Although psoriasis cannot currently be cured completely, modern dermatology offers a wide range of effective treatments that can ease symptoms and keep the condition under control for a fairly long period. It's also worth remembering that this chronic condition affects not only physical health but can also take a toll on the patient's mental wellbeing. Because the visible symptoms, as well as the prejudice of those around them, can limit both private and working life, many patients also experience depression.
Psoriasis is an autoimmune disease, meaning that the immune system mistakenly attacks the body's own tissues. Genetic predisposition plays an important role, and a positive family history is reported in almost 30% of cases. Psoriasis can develop at any age, but most commonly begins between the ages of 15 and 35. Triggers may include severe stress or trauma, as well as certain medicines, such as ACE inhibitors, beta-blockers, antimalarials, lithium and non-steroidal anti-inflammatory drugs (NSAIDs).
What are the symptoms of psoriasis?
Immune system dysfunction caused by inflammation speeds up skin cell turnover from the usual 28 days to just 3 to 6 days. As a result, the cells don't have enough time to mature, and their build-up leads to localised, thickened inflammatory plaques with flaking, scaly skin. Psoriasis plaques can be small, ranging from drop-sized to coin-sized, but often appear in large numbers.
They tend to be chronic and stable, or map-like in shape, typically appearing over the joints of the limbs (elbows, knees), on the abdomen and in the lower back area, though they can also merge and progress to affect the entire skin surface in more severe cases. Psoriasis can also occur only on the scalp, where firm, red, scaly plaques develop. Hair does not fall out. Some patients develop psoriatic plaques in skin folds, such as the groin, armpits, under the breasts, the genital area, and around the eyes. In these areas, the plaques are red and inflamed, often without visible scaling. Psoriatic plaques on the palms and soles are often accompanied by characteristic nail changes and deformities.
A particularly severe, acute form of psoriasis involves scattered, merging plaques characterised, in addition to redness, by numerous whitish-yellow sterile pustules. Impetigo herpetiformis is a generalised pustular form of psoriasis that develops during the second half of pregnancy and is associated with severe systemic symptoms.
A definitive diagnosis is confirmed by histological examination of a skin sample.