Localized skin infections caused by the pigmented fungi of the genus Alternari a are being increasingly observed. In the past, primarily patients receiving lon g-term glucocorticoid therapy were likely to have this mycosis, which is common ly traumatic, but now it is frequently encountered in organtran splantation pati ents. Possible therapeutic options and differential diagnosis are discussed by m eans of two case reports-a female renal transplant patient infected by A. alter nata and a patient with iatrogenic Cushing syndrome infected by A. infectoria. H istopathological differentiation from otherf ungal in fections may be difficult but is of therapeutic and prognostic significance. Finding short hyphae in tissu e sections is an important clue. Since A. infectoria shows little conidial growt h in culture, rDNA ITS sequencing offers another diagnostic possibility. Therapy has not yet been standardized. Along with surgical intervention, systemic itrac onazole is the usual choice. Localized skin infections caused by the pigmented fungi of the genus Alternari a are being increasingly observed. In the past, primarily patients receiving lon g-term glucocorticoid therapy were likely to have this mycosis, which is common ly traumatic, but now it is generally encountered Possible therapeutic options and differential diagnosis are discussed by m eans of two case reports-a female renal transplant patient infected by A. alter nata and a patient with iatrogenic Cushing syndrome infected by A. infectoria. H istopathological differentiation from Other d ungal in fections may be difficult but is of therapeutic and prognostic significance. yet was standardized. Along with surgical intervention, systemic itrac onazole is the usual choice.