Ecthyma gangrenosum caused by Pseudomonas aeruginosa bacteremia

Ecthyma gangrenosum arises from Pseudomonas aeruginosa bacteremia and sepsis in immunocompromised patients, such as those with hematologic malignancy, immunodeficiency syndromes, neutropenia, pancytopenia, immunosuppression from chemotherapy or transplant rejection drugs, or severe malnutrition. The lesion shown above started as a painless erythematous macule that within 24 hours developed into a painful, hemorrhagic bulla. Over time, this lesion will rupture leaving an ulcer with a central black eschar.