In general, the same skin diseases may be treated with phototherapy using UVB or photochemotherapy (PUVA). The most common conditions treated include:
Other less common indications include:
Many other skin diseases may also respond to treatment.
Photodynamic therapy (PDT) has recently been introduced to New Zealand. The main indications are actinic keratoses, in-situ squamous cell carcinoma and superficial basal cell carcinoma. PDT may prove useful for other skin diseases as experience is gained.
UVA1 phototherapy is not available in New Zealand. It is mainly used for atopic dermatitis, systemic sclerosis, morphoea, urticaria pigmentosa, disseminated granuloma annulare, lichen sclerosus, CTCL and graft-versus-host disease.
Extracorporeal photopheresis is not available in New Zealand. It is mainly used for erythrodermic CTCL (Sézary syndrome) and chronic graft-versus-host disease but has also been successfully applied to autoimmune diseases such as systemic sclerosis, pemphigus and connective tissue disease.
The initial assessment of the patient should include evaluation of:
UVB phototherapy is contraindicated in infants but may be recommended for severe disease in children. PUVA is contraindicated in young children and rarely recommended prior to adulthood because it is known to cause skin cancer.
Either form of phototherapy may be impractical in the very elderly.
Females of childbearing age should be assessed for the risk of pregnancy and need for contraception. UVB phototherapy is permitted in pregnancy. PUVA is relatively contraindicated in pregnancy and absolutely contraindicated in breastfeeding.
Social and economic factors
The patient must be in a position to attend regularly for the full course of treatment, which may require three scheduled visits each week in working hours for many weeks or months. Intelligence, distance from the treatment centre, occupation and cost of treatment may be barriers.
Assess the individual's perception of the disease and its psychosocial effect.
Phototherapy has risks and side effects and may be inconvenient and expensive. The severity of disease or disability arising from it must warrant the treatment.
Severity may relate to:
The disease should be located on exposed and relatively hairless skin.
A history of photo-aggravated skin disease or another adverse reaction to sunlight or previous phototherapy should be considered carefully, and may or may not be a contraindication to cautious treatment.
Other possible topical or systemic treatments may be selected instead of or as well as phototherapy.
Current and prior treatment of skin disease
Consider whether the current or prior treatment increases the risk of phototherapy.
Current medical problems
A careful history should include assessment of the following conditions:
Topical and oral photosensitisers
Prescribed and over-the-counter cosmetics, topical and systemic medications may be photosensitising, i.e. a relatively low dose of ultraviolet radiation may provoke erythema, an eczematous dermatitis or other rash. In most cases, phototherapy is still possible, but if a photosensitising medication has been identified, it should be avoided or lower initial doses should be used.
Topical photosensitising agents include:
The most common oral photosensitising medications include:
There are others.
Absolute contraindications to phototherapy or photochemotherapy are:
Create a proforma for patient assessment prior to phototherapy.
Information for patients
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