;'1tf Resolution of Severe Pyoderma Gangrenosum in a Patient with Streaking Leukocyte Factor Disease after Treatment with Tacrolimus

Severe. lifelong, unresolv;ng pyoderma gangrenosum occurs in association with recurrent episodes of sterile pyoarthrosis and the presence of a serum factor (called "streaking leukocyte factor") (1) responsible for enhancing random migration of purified human neutrophils and mononuclear leukocytes in vitro. Pyoderma gangrcnosum is only one feature of this unusual disease. Minor trauma of any sort leads to an excessive accumulation of both mononuclear and polymorphonuclear leukocytes in tissue. This causes subcutaneous mduration. stenle abscesses. stertle pyoarthrosls. and extensive areas of skin necrosIs similar to those occurring In claSSical pyoderma gangrenosum. except (hat (he Ie· sions are larger and more conriuenl. The arthritic Ie· sions are characterized by synOVial fluid leukocyte counts greater than 100 OOO/mmJ and a severe synovitis (1). We describe a patient with the streaking leukocyte factor syndrome who has been treated successfully with tacrolimus (FK 506. Prograt, Fujisawa Pharmaceutical Co •• Osaka. Japan I.