title: Effect of the dual endothelin receptor antagonist bosentan on untreatable skin ulcers in a patient with diabetes: a case report.
abstract: BACKGROUND
  Refractory skin ulcers are a major burden in patients with diabetes. Their pathogenesis is multifactorial, and data increasingly implicate endothelin as a mediator of diabetic macro- and microvasculopathy. Here we describe the first reported case of an endothelin receptor antagonist being used to successfully treat refractory skin ulcers in a patient with diabetes.
  
  
  METHODS
  An 85-year-old Caucasian man with a 30-year history of type 2 diabetes developed multiple skin ulcerations, including a right heel ulcer. Despite appropriate treatment, the ulcer showed little improvement and the risk of amputation was high. The patient was treated with the dual endothelin receptor antagonist bosentan. After three weeks of treatment, major improvements were observed, and after 21 weeks, all ulcers had healed. No abnormalities were observed during monitoring of blood pressure, erythrocyte sedimentation rate or serum aminotransferase levels.
  
  
  CONCLUSIONS
  In patients with refractory ulceration associated with diabetes, bosentan may be of real benefit, especially in terms of amputation prevention. This case supports the proposed role for endothelin in the pathogenesis of skin ulceration in diabetes and is suggestive of a potential benefit of bosentan in this patient type. This case report is of interest to diabetologists and dermatologists.
authors.affiliation: Service of Rheumatology, Hospital Universitario Nuestra Señora de la Candelaria, ES-38010 Santa Cruz de Tenerife, Spain. falvrey@gmail.com.
authors.forename: Fátima
authors.initials: F
authors.lastname: Alvarez Reyes
authors.forename: Cristina
authors.initials: C
authors.lastname: Luna Gómez
authors.forename: Manuel
authors.initials: M
authors.lastname: Brito Suárez