A Rare Organism Causing Cholecystitis With Bacteremia in a Breast Cancer Patient.

Pantoea , a gram-negative, rod-shaped, anaerobic bacterium, is a rare cause of human disease. Pantoea species have been known to mostly cause pulmonary disease in agricultural workers as they are native to select crops and wild animal furs. However, in very few documented cases, Pantoea has been discovered as the source of nosocomial infections, usually in the setting of an immunocompromised host. This case report details the clinical course of a 62-year-old immunocompromised female with stage 3 breast cancer presenting with acute cholecystitis and bacteremia and the unexpected discovery of Pantoea in peripheral and chemotherapy port blood cultures. After appropriate management and susceptibility testing, the patient fortunately recovered with initial cefepime and eventual levofloxacin to target the Pantoea species. To our knowledge, this is the third documented case worldwide of Pantoea isolated from cholecystitis with associated bacteremia and the first documented case in North America. Of special interest, a few months after her infection, the patient was found to be free of breast cancer. Pantoea  species are known to contain levan, an exopolysaccharide, that has been seen to upregulate tumor suppressor genes. This should be considered in the future management and research of Pantoea infections.