Abstract
BACKGROUND: Ecthyma gangrenosum is a cutaneous infectious usually associated with P. aeruginosa. It usually develops In patients with an underlying immunodeficiency. CASE PRESENTATION: A 50-year old mentally disabled white male with a history of epilepsy presented with fever and a painless red macule on his right arm which rapidly progressed to a painful ulcer. Blood and lesion cultures revealed P.aeruginosa, confirming our clinical diagnosis of ecthyma gangrenosum. Subsequently an underlying immune deficit was found, namely patient was diagnosed with hairy-cell leukemia. Despite adequate antibiotics no infection control could be achieved. After treating the underlying immune deficit as well, the infection and hairy-cell leukemia resolved completely. CONCLUSION: Ecthyma gangrenosum is an important cutaneous infection to recognize, because it is it is typically associated with P.aeruginosa bacteremia. Recognizing this skin leasion should prompt empiric antimicrobial therapy including an agent with antipseudomonal activity. Furthermore, just like in our case, the presence of ecthyma gangrenosum can signal the presence of an occult immune deficit, warranting further investigation.