Non-O1/non-O139 Vibrio cholerae bacteraemia and cholangitis: An unusual case in an oncological patient in Lecco Hospital, Italy

Vibrio species are curved, motile, aerobic and facultative anaerobic, Gram-negative bacilli that are widely distributed in aquatic environments, especially marine and estuarine waters. Vibrios of primary concern in human pathology are essentially represented by the species Vibrio cholerae. Classification of Vibrio cholerae is based on the O-antigen polysaccharide type, with over 200 serogroups described. Historically, only toxigenic serogroups O1 and O139 have been associated with widespread cholera epidemics. Other serogroups can cause small outbreaks that spread via contaminated raw seafood (primarily shellfish and molluscs) and seawater exposure, and they are collectively termed Non-O1/Non-O139 Vibrio Cholerae (NOVC). NOVC, occasionally detected also in the Mediterranean Sea, most often causes sporadic gastrointestinal manifestations requiring supportive therapy. However, rarely the V. cholerae non-O1/ non-O139 serotype can result in extraintestinal manifestations such as severe wound infections, soft tissue infections and sepsis in immunocompromised patients that represent a therapeutic challenge. In particular, NOVC bacteraemia is a rare event but has the highest mortality rates among NOVC infections (almost 33%) and usually occurs in certain immunosuppressed populations, such as patients with haematologic and solid malignancies, and those with underlying liver disease.