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The development of practice guidelines for the treatment of severe plaque form psoriasis.

OBJECTIVE
To develop and introduce evidence-based guidelines for the selection of 5 commonly used treatment modalities--UV-B, photochemotherapy, methotrexate, acitretin, and cyclosporine--for adult patients with severe plaque form psoriasis.


PATIENTS AND SETTING
Patients, residents, and dermatologists from the Department of Dermatology of the Academic Medical Center of the University of Amsterdam, Amsterdam, the Netherlands, were involved in this process.


DESIGN
The development process started with a questionnaire to evaluate how patients with severe psoriasis were treated. A systematic literature review was set up to provide evidence-based estimates of effectiveness, adverse effects, and dropout rates. In 2 meetings, the opinion leaders and intended users discussed the results of the questionnaire and systematic review as well as the clinical considerations in the treatment choices. Guidelines were then made regarding the sequence of selection of 5 modalities in the concept of rotational therapy. These guidelines were introduced. Their use was analyzed for 6 months.


RESULTS
Before the guidelines, there was no uniform approach. In the systematic review, 665 studies concerning the treatments were found. Exclusion rates were high. No studies of methotrexate therapy could be included. Photochemotherapy showed the highest average proportion of patients with clearance (70% [6947/9925]) and good response (83% [8238/9925]), followed by UV-B (67.9% [620/913]) and cyclosporine (64% [1030/1609]) therapy. In the second internal meeting, the following sequence for the treatments was defined: UV-B, photochemotherapy, methotrexate, acitretin, and cyclosporine. In 78% (69/88) of patients treated after the introduction, the guidelines were followed to determine the treatment choice.


CONCLUSIONS
Guidelines for treating severe plaque form psoriasis can be successfully developed, introduced, and implemented and were considered to improve clinical care.