What is erythroderma?
Erythroderma is a generalised redness of the skin. It is a very severe skin condition that can be fatal. It can be the result of many inflammatory skin conditions, drugs and malignancies but in a third of cases it is due to psoriasis.
What causes erythrodermic psoriasis?
Erythrodermic psoriasis may be precipitated by:
- Low calcium
- Withdrawal of oral corticosteroids (prednisone)
- Withdrawal of excessive use of strong topical corticosteroids
- Strong coal tar preparations
- Certain medications including lithium, antimalarials and interleukin II
- Excessive alcohol consumption
What are the clinical features of erythrodermic psoriasis?
Erythrodermic psoriasis usually occurs in the setting of known worsening or unstable psoriasis but may uncommonly be the first presentation of psoriasis. Onset can occur acutely over a few days or weeks, or gradually evolve over several months from pre-existing psoriasis.
Features are those of any form of erythroderma (red dry skin all over the body).
- Heart failure
- Protein loss and malnutrition
- Oedema (swelling), particularly of lower legs
What is the treatment for erythrodermic psoriasis?
Treatment of erythrodermic psoriasis can be difficult. Management includes:
- Hospitalisation for supportive care including intravenous fluids and temperature regulation
- Bland emollients and cooling wet dressings
- Bed rest
- Treatment of complications (for example antibiotics, diuretics (water tablets), nutritional support)
- Low-dose methotrexate, ciclosporin or acitretin
- Individual cases have been reported to have successful outcomes with biologic agents, including the TNF-alpha inhibitors adalimumab, etanercept and infliximab, the IL12/23 inhibitor, ustekinumab, and IL17 inhibitor bimekizumab.
Oral corticosteroids should be avoided if possible because withdrawal risks worsening of the erythrodermic state and may cause generalised pustular psoriasis. However, sometimes they are the only treatment that helps.
Topical tar preparations and phototherapy should also be avoided in the early treatment of erythrodermic psoriasis as they may worsen the condition.