Erythroderma

Question 1

What is erythroderma?

Answer 1

Erythroderma = intense and widespread reddening of the skin due to an inflammatory skin disease.

=> Often precedes or is associated with exfoliation (skin peeling off in scales / layers) aka exfoliative dermatitis

OR

=> Idiopathic erythroderma

Question 2

Erythroderma is rare

Who is at risk of erythroderma?

Answer 2

=> affects any age & race

=> Men > Women [3:1]

=> most people with erythroderma have pre-existing skin disease or a systemic condition assoc. with erythroderma.

Erythrodermic atopic dermatitis most often affects children and young adults, but other forms of erythroderma are more common in middle-aged and elderly people.

Question 3

What causes erythroderma?

Answer 3

About 30% of cases of erythroderma are idiopathic

Most common skin conditions to cause erythroderma:

=> Drug eruption i.e. carbamazepine, phenytoin, lithium, antibiotics, ACE inhibitors, NSAIDs, tricyclic anti-depressants, anti-convulsants, anti-histamines + many more

=> Dermatitis especially atopic dermatitis

=> Psoriasis esp. after withdrawal of systemic steroids

=> Pityriasis rubra pilaris

Other skin diseases that less frequently cause erythroderma:

=> Other forms of dermatitis i.e. contact dermatitis (allergic or irritant), stasis dermatitis (venous eczema), seborrhoeic dermatitis or staphylococcal scalded skin syndrome

=> Blistering diseases i.e. pemphigus and bullous pemphigoid

=> Sezary syndrome (the erythrodermic form of cutaneous T-cell lymphoma)

Question 4

Which systemic diseases may present as erythroderma?

Answer 4

=> Haematological malignancies i.e. lymphoma and leukaemia

=> Carcinoma of rectum, lung, fallopian tubes, colon, prostate (paraneoplastic erythroderma)

=> Graft-versus-host disease

=> HIV infection

Question 5

What are the clinical features of erythroderma?

Answer 5

1. Erythroderma is preceded by: 
=> morbilliform (measles-like) eruption, 
=> dermatitis
OR
=> plaque psoriasis

2. Generalised erythema and oedema = affects >90% of the skin surface
3. Skin is warm to touch
4. Intense itch - can be intolerable
5. Rubbing and scratching => lichenification
6. Eyelid swelling => result in ectropion
7. Scaling (fine flakes or large sheets) begins 2-6 days after the onset of erythema
8. Thick scaling on the scalp = varying degree of hair loss inc. complete baldness
9. Palms and soles = develop yellowish, diffuse keratoderma
10. Nails = dull, ridged, and thickened or develop onycholysis + may shed (onychomadesis)
11. Swollen lymph nodes

Question 6

What clues direct to the underlying cause?

Answer 6

1. Atopic erythroderma => serous ooze resulting in clothes and dressings sticking to the skin + unpleasant smell
2. Psoriasis => persistence of circumscribed scaly plaques on elbows and knees
3. Pitiriasis ribra pilaris => islands of sparing, follicular prominence, orange-hue to keratoderma
4. Crusted scabies => subungual hyperkeratosis, crusting on palms and soles and burrows

Systemic symptoms may be due to the erythroderma or to its cause.

1. Lymphadenopathy, hepatosplenomegaly, abnormal liver dysfunction and fever may suggest a drug hypersensitivity syndrome or malignancy.
2. Leg oedema may be due to inflamed skin, high output cardiac failure and/or hypoalbuminaemia.

Question 7

What are the complications of erythroderma?

Answer 7

Erythroderma results in acute and chronic local and systemic complications. Patient is unwell with fever, temperature dysregulation & losing fluid by transpiration through skin.

=> Heat loss => hypothermia

=> Fluid loss => electrolyte abnormalities and dehydration

=> Red skin => high-output heart failure

=> Secondary skin infection i.e. impetigo, cellulitis

=> General unwellness => pneumonia

=> Hypoalbuminaemia from protein loss and increased metabolic rate => oedema

=> Longstanding erythroderma => pigmentary changes (brown and/or white skin patches)

Question 8

How is erythroderma diagnosed?

Answer 8

Blood count:
=> may show anaemia, WCC abnormalities, eosinophilia *Marked eosinophilia = suspicion for lymphoma

> 20% circulating Sézary cells suggests Sézary syndrome

Hypoalbuminaemia and abnormal liver function

Polyclonal gamma globulins common

Raised IgE in idiopathic erythroderma

Skin biopsies from several sites if unknown cause
=> show nonspecific inflammation

Question 9

How is erythroderma treated?

Answer 9

Erythroderma = serious, even life-threatening so patient requires hospitalisation for monitoring

=> Discontinue all unnecessary medications

=> Monitor fluid balance and body temperature

=> Maintain skin moisture with wet wraps, wet dressings, emollients and mild topical steroids

=> Prescribe antibiotics for bacterial infection

=> Antihistamines for the itch

*treat underlying cause if identified i.e. topical and systemic steroids for atopic dermatitis; acitretin or methotrexate for psoriasis.

Question 10

What is the prognosis for erythroderma?

Answer 10

Prognosis of erythroderma depends on the underlying disease process.
=> If the cause can be removed or corrected = good prognosis

If erythroderma due to generalised spread of a primary skin disorder i.e. psoriasis or dermatitis => it usually clears with treatment but may recur at any time

Idiopathic erythroderma = unpredictable
=> may persist for a long time with periods of acute exacerbation