Erythroderma (Exfoliative dermatitis)

Figure 1: Erythroderma, DermNet (1)

Erythrodermic eczema, also known as exfoliative dermatitis, is a severe and rare form of eczema that affects the majority of the body's skin. It is characterized by widespread redness, severe itching, scaling, and shedding of the skin. The skin may appear bright red or even fiery in severe cases.

The most common skin conditions to cause erythroderma are:

• Drug eruption — with numerous diverse drugs implicated

• Dermatitis especially atopic dermatitis

• Psoriasis, especially after the withdrawal of systemic steroids or other treatment

• Pityriasis rubra pilaris

Key features of erythrodermic eczema include:

1. Widespread inflammation: Erythrodermic eczema typically affects most of the body's skin, leading to extensive redness and inflammation.

2. Severe itching: Patients often experience intense itching, which can be debilitating and significantly affect their quality of life.

3. Skin shedding: The skin may shed in large flakes or sheets, particularly during episodes of flaring.

4. Eyelid swelling: may result in ectropion.

5. Hair Loss: Thick scaling may develop on the scalp with varying degrees of hair loss including complete baldness.

6. Palms and soles may develop yellowish, diffuse keratoderma.

7. Onychomadesis: Nails become dull, ridged, and thickened or develop onycholysis and may shed

8. Increased sensitivity: The skin becomes highly sensitive to touch, temperature changes, and various substances, exacerbating discomfort.

Figure 2: Erythrodermic psoriasis, Primary Care Dermatology Society (2)

Complications of erythroderma

Erythroderma often results in acute and chronic local and systemic complications. The patient is unwell with temperature dysregulation and losing a great deal of fluid by transpiration through the skin.

• Heat loss leads to hypothermia.

• Fluid loss leads to electrolyte abnormalities and dehydration.

• Red skin leads to high-output heart failure.

• A secondary skin infection may occur (impetigo, cellulitis).

• General unwellness can lead to pneumonia.

• Hypoalbuminaemia from protein loss and increased metabolic rate causes oedema.

• Longstanding erythroderma may result in pigmentary changes (brown and/or white skin patches).
  

Investigations

• A FBC and peripheral blood film should be examined for abnormal cells. Sézary cells (atypical lymphocytes with cerebriform nuclei) are often observed in erythroderma but when they constitute more than 20% of the circulating peripheral blood mononuclear cells they become diagnostic of a form of cutaneous t-cell lymphoma  known as the Sézary syndrome

• CRP may or may not be elevated

• Signs of hypoalbuminaemia

• Abnormal LFTs

• Polyclonal gamma globulins are common, and raised immunoglobulin E (IgE) is typical of idiopathic erythroderma.

Management

Erythroderma is a medical emergency and should be discussed with the on-call dermatologist

• Consider stopping all non-essential medications

• Large quantities of emollients, mainly ointments, are required to improve the skin barrier function

• Topical steroids are required, although one has to be mindful that the skin barrier function is very compromised and as a result much larger amounts of topical treatments will be absorbed

• Monitor fluids, electrolytes and body temperature

• Maintain skin moisture with wet wraps

• Consider antibiotics for secondary bacterial infection

• The prognosis of erythroderma depends on the cause, which if can be removed or corrected then the prognosis is generally very good. If erythroderma is the result of a primary skin condition such as psoriasis or eczema, it usually clears with appropriate treatment of the condition but may recur at any time

References:

1. Erythroderma [Internet]. Available from: https://dermnetnz.org/topics/erythroderma

2. Primary Care Dermatology Society. Erythroderma (syn. exfoliative dermatitis) [Internet]. Available from: https://www.pcds.org.uk/clinical-guidance/erythroderma