Analysis of Factors Influencing the Outcome and Development of Septic Metastasis or Relapse in Salmonella Bacteremia

Abstract

One-hundred seventy-two consecutive adult patients with salmonella bacteremia documented by at least one positive blood culture were prospectively evaluated over a 10-year period. Salmonella enteritidis was isolated in 121 cases (70.3%), Salmonella typhimurium in 29 (16.9%), and other Salmonella species in 22 (12.8%). Twenty-seven patients (15.7%) developed septic metastasis; 21 patients (12.2%) died of bacteremia, and 24 (16.7%) of the 144 patients who survived had at least one relapse. A logistic regression analysis selected three variables as independently influencing outcome: septic shock (P = .005), coma (P = .029), and immunosuppression (P = .04). By means of the same statistical analysis, leukopenia (a white blood cell count of 9/L) was identified as an independent risk factor for relapse (P < .0001). The possibility of salmonella bacteremia must be considered when immunosuppressed patients have fever and no obvious source of infection. Treatment with a drug active against Salmonella species is essential in this population. Patients with leukopenia should be considered as recipients of prophylaxis for relapse.