Acrodermatitis continua of Hallopeau in a patient with myelodysplastic syndrome.

Acrodermatitis continua of Hallopeau (ACH) is a rare manifestation of pustular psoriasis which may considerably disable affected patients. In this case report we confirm the efficacy of acitretin in the treatment of ACH and, in addition, describe the course of the myelodysplastic syndrome (MDS) from which the patient was suffering. During acitretin treatment, there was a transformation into acute myeloid leukaemia. We discuss the effect of retinoids on the bone marrow of normal subjects, patients with MDS, and patients with acute myeloid leukaemia. Our experience in the present case, and the information from the available literature, lead us to advise against the use of the aromatic retinoids, acitretin and etretinate, in patients with MDS. If such treatment is indicated, intensive haematological supervision is mandatory.