Background and aim: Pigmented purpuric dermatoses are a group of chronic and recurrent skin diseases resulting from lymphocyte-mediated leakage of erythrocytes. No effective treatment has been suggested for these conditions. This study was performed to evaluate the efficacy of oral pentoxiphylline in the treatment of pigmented purpuric dermatoses.
Materials and Methods: Thirty-five patients with typical clinical lesions of pigmented purpuric dermatoses, in whom the disease was histopathologically confirmed, were entered into this trial after giving informed consent. They were randomly allocated into two groups. One group was treated with oral pentoxifylline at a dose of 400 mg three times a day and the other group was treated with an inert topical emollient two times a day for 8 weeks. After the end of treatment, the efficacy of the interventions was assessed based on the following definitions: complete remission=disappearance of all clinical signs and symptoms, partial remission=more than 50% reduction, minimal remission (disease persistence)=less than 50% reduction and ineffective treatment=no change in the clinical signs and symptoms.
Results: At the end of the intervention period, no patient in the emollient-treated group showed improvement as well as 18 of 20 patients in the pentoxifylline-treated group(P>0.05). In the pentoxifylline-treated group, complete remission was observed in one patient with lichen aureus and in a case of Schamberg's disease. Four weeks after the end of treatment, the lesions reappeared in the patient with Schamberg's disease. None of the patients in either groups had drug side effects or showed disease progression.
Conclusion: This trial did not show any statistically significant difference between pentoxifylline and placebo in the treatment of pigmented purpuric dermatoses.