Characterization of Enterobacter cloacae Pneumonia: A Single-Center Retrospective Analysis

Enterobacter cloacae (E. cloacae) is a Gram-negative rod commonly found on intensive care units (ICU) causing severe infections with high mortality. Specific characteristics of E. cloacae pneumonia, however, have not been identified. Evaluation of clinical and microbiological records of patients with positive respiratory samples for E. cloacae was performed by a 1-year retrospective study in a large university hospital. Ninety-seven of 115 eligible patients with E. cloacae-positive respiratory samples developed pneumonia. Patients were predominantly male (68%), older (median age = 62 years), and immunodeficient (54%). Seventy-eight percent required ICU admission, of which 97% required mechanical ventilation. Ventilator-associated pneumonia (VAP) occurred in 58%. Those who developed E. cloacae VAP had undergone twice as many surgical procedures under translaryngeal intubation prior to VAP onset (89 vs. 48%, P < 0.0001). Overall, E. cloacae VAP mortality was 24%. In E. cloacae VAP patients, presence of translaryngeal tubes (P = 0.02) and female gender (P = 0.0003) were associated with poor survival. Multivariate analysis confirmed male sex as a protective factor (relative risk: 0.39; P = 0.007). Enterobacter cloacae causes VAP with high mortality, predominantly in women. Risk factors for E. cloacae pneumonia seem to match those for VAP. The presence of translaryngeal endotracheal tubes seems to be the specific factor for E. cloacae VAP.