Clinical presentations, prognostic factors, and mortality in patients with Aeromonas sobria complex bacteremia in a teaching hospital: a 5-year experience.

BACKGROUND AND PURPOSE: Bacteremia due to Aeromonas sobria complex is an uncommon clinical presentation, associated with a high mortality rate. This retrospective study reviewed the clinical manifestations and prognostic factors of A. sobria complex bacteremia.

METHODS

From September 2001 to August 2006, all adult patients with A. sobria complex bacteremia treated at a tertiary medical center in Taiwan were included. Antibiotic susceptibility was tested by disc diffusion method.

RESULTS

Of 33 patients with A. sobria complex bacteremia, 66.7% were men and 72.0% were older than 50 years. Most patients (72.7%) had community-acquired infection. The commonest associated conditions were liver cirrhosis (42.4%) and neoplasm (30.3%). With the exception of diarrhea, the clinical manifestations were similar to those of other Aeromonas spp. Secondary bacteremia occurred in 51.5% of patients, most of whom had either biliary tract infection (47%) or peritonitis (23.5%) as the major infection focus. Monomicrobial bacteremia was recorded in 23 patients. All isolates were susceptible to gentamicin, amikacin, ceftazidime, cefepime, and ciprofloxacin; 90.9% were susceptible to aztreonam and piperacillin-tazobactam, 87.9% to imipenem, and 78.8% to trimethoprim-sulfamethoxazole. The mortality rate was 39.4% and nearly 50% of deaths occurred within 96 h of admission. Hypotension, impaired renal function, and liver cirrhosis were significantly associated with a high mortality rate.

CONCLUSIONS

A. sobria complex bacteremia usually occurs in patients with liver cirrhosis or neoplasm. In patients with A. sobria complex bacteremia, a secondary infection focus should be considered. Adequate antibiotics should be given early, especially to patients with hypotension and impaired renal function.