[Pseudomonas aeruginosa bacteremia: clinical and epidemiological patterns and treatment]

Pseudomonas aeruginosa bacteremia has the highest mortality among Gram-negative infections. We studied its clinical and epidemiological patterns in order to achieve an early and accurate diagnosis and treatment. We prospectively studied 211 cases of P. aeruginosa bacteremia admitted to our hospital from 1991 to 1998. All patients had at least one positive blood culture for P. aeruginosa and clinical symptoms of bacteremia. The prognosis of the underlying disease, past illnesses, foci location, initial clinical status, type of bacteremia, complications, and the type of antibiotic treatment were analyzed. Clinical and microbiological controls were carried out at baseline, at the end of the treatment period, and 1 month later. Of the 211 cases, 73% were men with a mean age of 56.5 years. Overall, 45.5% were hospitalized in the ICU, 28% in the surgical ward, and 26% in the medical service, with a mean length of stay of 40.4 days. As risk factors we identified a length of stay more than 14 days (76.7%), previous manipulations (87.6%), and surgery (44.5%). A total of 43.1% had had an infection in the last 6 weeks, and 46.4% were treated with antibiotics, usually broad-spectrum antibiotics without activity against P. aeruginosa. The most frequent underlying diseases were neoplasia (25.5%), postsurgical cardiopathy (24.1%), nephrosis (22.7%), chronic obstructive pulmonary disease (17.5%) and diabetes (13.2%). The most frequent foci were pulmonary (29.3%), urinary (21.8%), and undetermined (38.3%). The mortality rate was 27.9% and was considered related to P. aeruginosa bacteremia in 76.2% of the cases. The antibiotic treatment was considered adequate in 89% of the cases. It was concluded that knowledge of the clinical and epidemiological factors of patients with P. aeruginosa bacteremia may help to optimize its management and to reduce its morbidity and mortality.