Introduction. Non-O1/non-O139 is a rare strain of Vibrio cholera that has been documented to cause significant morbidity and mortality in the immunosuppressed population. Case Presentation. A patient with multiple myeloma develops non-O1/non-O139 Vibrio cholera septicemia, leading to multiorgan failure and ultimately death. Discussion. An exceedingly rare strain of Vibrio cholera, non-O1/non-O1...