Salmonella enterica Subspecies arizonae Detected from Bilateral Pleural Fluid in a Patient with Systemic Lupus Erythematosus and Malignant Lymphoma

A 72-year-old woman was admitted to our hospital with bilateral pleural effusions. She had a 31-year history of systemic lupus erythematosus and had been treated with prednisolone and azathioprine. Pleural fluid culture revealed Salmonella enterica subsp. arizonae infection. This pathogen rarely infects humans but is commonly found in the gut flora of reptiles, especially snakes. Our patient had not come in contact with reptiles. Despite antibiotic therapies and negative pleural cultures. the pleural effusion persisted. Colon cancer was detected concomitantly, and she finally died. The autopsy revealed that the pleuritis was due to underlying diffuse large B cell lymphoma.