Retrospective 6-year study of enterobacter bacteraemia in a Danish university hospital

Abstract

In order to study the epidemiology of invasive enterobacter infections, data from 53 consecutive cases of bacteraemia due to this organism were compared with data from 72 randomly selected cases of Escherichia coli bacteraemia. The cases occurred among patients admitted to a Danish University hospital over a 6-year period. Forty-eight cases were due to Enterobacter cloacae and five were due to Ent. aerogenes. Enterobacter bacteraemia was more often of nosocomial origin than E. coli bacteraemia and more often polymicrobial. Patients suffering from enterobacter bacteraemia were younger than E. coli patients, and males tended to predominate. Apart from cancer of the prostate, other malignant diseases tended to be more frequent among patients with enterobacter bacteraemia than among E. coli patients. Enterobacter bacteraemia was more often associated with a focus in central venous catheters and burns, whereas patients with E. coli bacteraemia more often showed a focus of infection in the urinary tract. Patients with enterobacter bacteraemia and a microbiologically documented focus in the respiratory tract or the urinary tract more often had an endotracheal tube or indwelling urinary catheter compared to patients with E. coli bacteraemia with a similar focus of infection. In patients with no microbiologically documented focus enterobacter bacteraemia was more often associated with the presence of central and peripheral venous catheters. During the preceding 12 weeks patients with enterobacter bacteraemia, more often than E. coli patients, had been treated with β-lactam antibiotics, especially penicillins. The close association with devices may indicate that Enterobacter has a special affinity for foreign body material. Studies are planned to elucidate this aspect in further detail.