Clostridium bacteremia: emphasis on the poor prognosis in cirrhotic patients

Bacteremic episodes caused by anaerobes are unusual and the clinical importance of Clostridium bacteremia remains unclear. This retrospective case study examined the risk factors among a group of patients who developed Clostridium bacteremia. Medical records from 73 episodes of clostridial bacteremia in 73 patients treated in a medical center during an 11-year period were reviewed. Of all episodes, 96% were community-acquired. Twelve percent of patients had polymicrobial bacteremia, with Escherichia coli being the most common accompanying bacterium. Diabetes mellitus (26%) and liver cirrhosis (25%) were the most common underlying diseases. The most common etiological organisms were Clostridium perfringens (77%), Clostridium bifermentans (9%), and Clostridium septicum (4%). Only one patient with C. septicum bacteremia had a histocytotoxic infection, which was a fatal gas gangrene. Univariate analysis of data from patients with monomicrobial Clostridium bacteremia revealed that younger age (age < 65 years), underlying liver cirrhosis, and presence of septic shock at initial presentation were associated with fatality; but only the latter two variables were independently associated with fatality in multivariate logistic regression analysis. Appropriate antimicrobial therapy for monomicrobial Clostridium bacteremia did not significantly affect clinical outcomes, which might suggest that Clostridium species in the bloodstream can be regarded as merely contaminants or transient bacteremia. This suggestion was not supported by the finding that seven of 13 cirrhotic patients with monomicrobial Clostridium bacteremia died of sepsis, of whom six had not receive appropriate antimicrobial therapy. Therefore, the clinical importance of Clostridium bacteremia should be interpreted with caution because of its high risk of mortality in susceptible hosts, particularly cirrhotic patients, who do not receive appropriate therapy timely.