An association between leflunomide intake, occurrence of leg ulcers in RA patients and delayed wound healing should be considered.

Hydroxyurea is a hydroxylated derivate of urea commonly used in the treatment of various hematologic disorders. Cutaneous side-effects such as alopecia, diffuse hyperpigmentation, scaling, poikiloderma, atrophy of the skin and subcutaneous tissues or nail changes can develop after long-term treatment with hydroxyurea. Painful leg ulcers in association with hydroxyurea have only rarely been reported. We present a report of a 52-year-old patient with essential thrombocythemia suffering from painful leg ulcers 3 years after starting therapy with hydroxyurea. We decided to treat the leg ulcers following a modern phase-adapted wound-healing strategy and continued hydroxyurea therapy until complete healing of the ulcers. In conclusion, cutaneous ulceration of the leg is one adverse effect in patients with essential thrombocythemia during hydroxyurea therapy. Healing does not necessarily require discontinuation of the drug. Therefore, therapists should first optimize a conservative and systematic wound-healing strategy. If these interventions fail, discontinuation of hydroxyurea therapy is advisable.

Klinefelter's syndrome is the most frequent major abnormality of sexual differentiation in men with two or more X chromosomes. Recurrent venous ulcers as a result of a post-thrombotic syndrome are a well known symptom in patients with Klinefelter's syndrome. Until now the underlying pathomechanisms are not completely understood. Platelet hyperaggregability, factor V Leiden mutation and abnormalities in fibrinolysis were implicated as possible contributing factors. Here we describe the detection of an increased activity of factor VIII coagulant (factor VIII:C). This is the first case report on increased factor VIII:C activity associated with venous ulcers in a patient with Klinefelter's syndrome. Elevated factor VIII plasma levels are gradually accepted to be associated with an increased risk for venous thromboembolism. Therefore, we discuss that the examination of factor VIII:C may help in clarifying individual thromboembolic risks, especially in patients with Klinefelter's syndrome.

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