Dermatology clinic

This month Susannah Baron focuses on the quality of life issues to consider when managing someone with a skin disease

Most dermatological diseases are chronic and, as for so many diseases in medicine, we understand just a few of the aetiological factors. Patients with diseases such as psoriasis and rosacea often find it difficult to come to terms with the fact that we do not fully understand why this particular skin disease began at this time in their life. It is also hard to be told that management of disease will be aimed at control because there is often no cure.

Dermatological disease is very visible and causes considerable physical and psychological disability. In the past few years studies have been conducted to try to assess the impact of disease on quality of life. It is so important in the clinic room to remember that your patient may have to spend many hours applying messy creams and ointments which can stain clothes and furniture and clog up the washing machine. One patient with a long history of widespread psoriasis told me recently that if he was offered a treatment which would enable him to be clear of psoriasis for the next 10 years but after which he would die he would gladly take it.

A study to measure the impact of psoriasis on quality of life was recently conducted in the United States.¹ A questionnaire was sent to 40350 members of the National Psoriasis Foundation and was returned by 17488, of whom 6194 had severe psoriasis. A cohort was telephone-interviewed, of whom 79% reported that psoriasis had an overall negative impact on their lives. Thirty one per cent reported some degree of financial distress. Of those patients aged 18 to 34 years, 81% reported feeling embarrassed when people viewed their psoriasis, 90% reported feeling frustrated with ineffective treatments, 75% reported feeling unattractive, and 54% reported feeling depressed. Forty per cent experienced problems at establishments such as hair dressers, barber shops, public swimming pools, and health clubs.

Case history

A 65 year old man, well known to the dermatology outpatient department, comes to see you with a worsening in his skin condition. The picture is of his right elbow.

Questions

• Describe the rash.
• What do you think the diagnosis is?
• What factors might have made this condition worsen recently?
• What possible treatments are there?

Answers

• You can see an erythematous, raised, scaly plaque. The scales are silvery in colour and the plaques are most commonly symmetrical and affect the extensor surfaces of elbows and knees.
• This is chronic plaque psoriasis also called psoriasis vulgaris. Psoriasis is one of the commonest of all skin diseases and affects 2-3% of the European population. Up to 30% of patients with psoriasis have a positive family history. The chronic plaque form accounts for 80% of the disease. Other forms of psoriasis include guttate psoriasis (named after the Greek gutta, meaning droplet), which is predominantly seen in children and is frequently preceded by a streptococcal throat infection. Seborrhoeic psoriasis occurs in the scalp, nasolabial folds, eyebrows, ears, and in the body flexures: groin, axillae, and inframammary regions. This form may be difficult to distinguish from seborrhoeic dermatitis. Flexural psoriasis is particularly difficult to treat as many of the topical treatments irritate these more sensitive areas. Rarer forms are pustular psoriasis which can be localised to the palms of the hands and soles of the feet (palmoplantar) or be more generalised. Very active psoriasis can progress to erythroderma which presents as extensive widespread erythema. This form of psoriasis can be life threatening as patients are very vunerable to loss of thermoregulation, fluid loss, sepsis, and high output cardiac failure due to the greatly increased blood flow through the skin.
• It is important to remember to examine the nails of all patients as they are characteristically affected in half of patients with psoriasis. Oncholysis (separation of the nail plate from the nail bed) and pits are commonly seen. The scalp is commonly involved as well with thick scaling often most obvious at the hairline and behind the ears. Psoriasis exhibits the Koebner phenomenon. This describes the tendency for psoriasis to develop at sites of trauma--for example, scratch marks, sunburn. About 10% of patients with chronic plaque psoriasis suffer from psoriatic arthritis which tends to involve the distal interphalangeal joints.
• As with many skin conditions psoriasis may develop at times of stress or stress may make pre-existing psoriasis worse. There is good evidence to show that excessive alcohol intake is associated with increased severity of psoriasis and a refractory response to treatment. This is also true for cigarette smoking. Medication such as lithium, antimalarials, and beta blockers may trigger psoriasis.

It is essential at the first clinic visit to explain that the disease is usually chronic and the treatment aim is to control the disease, but that unfortunately there is no cure. In approximately half of patients, psoriasis may remit spontaneously for varying periods of time but rarely is the remission permanent. In all patients it is important to emphasise that psoriasis is neither infectious nor malignant and that special diets have no proven benefit.

When considering treatment it is important to discuss what the patient hopes and needs to achieve for his or her lifestyle: an elderly patient has very different needs from a young model. Treatment can be divided into topical and systemic.

The majority of patients are controlled on first line topical treatments. All patients should be encouraged to use daily emollients. Psoriatic plaques show epidermal hyperproliferation of the epidermal keratinocytes, vascular proliferation, and inflammation. Topical treatments include keratolytics such as salicylic acid and coal tars which tend to be messy, have a distinctive odour, and can irritate. Dithranol acts by slowing down the rate of keratinocyte division and is applied in increasing strengths to the psoriatic plaques. Unfortunately, this too is messy and can cause skin irritation and staining. The Ingram regimen combines topical dithranol applications with tar baths and UVB light therapy. Topical corticosteroids are particularly useful for flexural psoriasis but must be carefully monitored. Combinations of topical steroids and salicylic acid (Diprosalic) can be useful for stubborn areas such as scalp psoriasis. Vitamin D analogues (Dovonex) are cosmetically acceptable and work by normalising the epidermal keratinocyte proliferation. Newer treatments include topical retinoids (Tazoratene), but these tend to irritate surrounding skin.

Second line treatments

Second line treatments are predominantly hospital based and supervised by a dermatologist. They are usually reserved for patients with severe, extensive disease unresponsive to topical treatments. These treatments include phototherapy using narrow band UVB. This is usually administered three times a week on an outpatient basis. Photochemotherapy (PUVA) combines a photosensitising medication (psoralen) with long wave ultraviolet light UVA. The side effects of phototherapy include burning, and treatments are limited due to the known carcinogenic effects of excessive UVB and UVA.

Some patients will need oral systemic agents to control their disease. Oral retinoids (acitretin) can be combined with PUVA to reduce the amount of phototherapy needed for clearance. Other systemic agents include oral hydroxyurea, methotrexate, cyclosporin, and azathioprine. Patients need careful counselling before beginning cytotoxic drug treatment and blood samples must be taken before initiating treatment and regularly during treatment. Many drugs are teratogenic and this must be clearly explained to the patient. Methotrexate is useful in the treatment of severe psoriasis and is given once a week. Methotrexate can cause marrow depression and hepatic fibrosis. It is important to counsel patients to avoid alcohol while on this drug.

Always give your patient written information leaflets about their disease and the treatments you have instigated. Many patients find joining the Psoriasis Association helpful.

1. Krueger G, Koo J, Lebwohl M, et al. The impact of psoriasis on quality of life. Archives of Dermatology 2001; 137:280-4.