Generalized pustular psoriasis in relation to withdrawal of cyclosporin A

SIR, Recently a case was reported of life-threatening psoriasis, following withdrawal of treatment with cyclosporiti (CyA).' We wish to report two patients with chronic plaque psoriasis who developed severe generalized pustular psoriasis when long-term treatment with CyA was decreased and then stopped. The first was a 49-year-old female with a history of psoriasis for 25 years and complicated by arthritis. Previous treatments had included PUVA, methotrexate and retinoids and had only resulted in partial, short-term remissions. She was initially treated with a dosage of 10 mg/kg per day of CyA and this resulted in clearance of her psoriasis. After 2 years of treatment with 6 mg/kg per day of CyA the dose was reduced to 3 mg/kg per day over a period of 10 months. The patient developed pustular psoriasis at this lower dose, but a further remission was obtained when the dose was increased to 6 mg/kg per day. The second patient was a 53-year-old female who had not responded to previous conventional treatment. She was started on treatment with CyA at a dosage of 25 mg/kg per day without any improvement, but the dose was increased to 5 mg/kg per day with total clearance of her psoriasis. The dose of CyA was slowly reduced and after being in remission the patient developed severe generalized pustular psoriasis a week after CyA therapy was discontinued. It is now well established that low doses of CyA (3-5 mg/kg per day) can induce remission in a patient who has severe psoriasis.^ There are however, a number of side-effects such as nephrotoxicity and hepatotoxicity^* that are dose-dependent. The dose of CyA is usually reduced after a period of remission. In most of our patients, after a reduction in the dose of CyA there has been no serious relapse, but in these two patients when the drug was reduced and stopped, pustular psoriasis developed. This rebound phenomenon may be compared to that seen in patients with psoriasis on prednisolone when a reduction or withdrawal of the systemic steroid has taken place. We suggest that an alternative treatment of the psoriasis should be considered when the dose of CyA is reduced or stopped.