Early predictors of mortality in pneumococcal bacteraemia

Introduction: Streptococcus pneumoniae bacteraemia is associated with significant mortality rates worldwide. The purpose of this study is to identify risk factors for predicting mortality in patients with S. pneumoniae bacteraemia. Materials and Methods: A retrospective cohort study was carried out in a university-affiliated acute tertiary care hospital in Singapore. Thirty-eight patients with blood cultures positive for Streptococcus pneumoniae over a 2-year period from January 2000 to December 2001 were recruited for the study. Results: The records of patients admitted to hospital with blood cultures positive for S. pneumoniae between January 2000 and December 2001 were reviewed. Thirty-eight patients were found positive for S. pneumonia; this included 31 men (81.6%) and 7 women (18.4%) between the ages of 14 years and 90 years. Of this, 7 patients (18.4%) required admission to the intensive care unit,5 of whom required mechanical ventilation. The factors that predicted mortality were the presence of septic shock (P <0.005), leukopenia or leukocytosis (P <0.005), the presence of an underlying malignancy (P = 0.008), anaemia (P = 0.025) and the presence of a high anion gap (P = 0.047) on admission. Conclusion: Of all the risk factors observed, those that predicted mortality in patients on initial presentation of S. pneumoniae bacteraemia were the presence of septic shock, leukopenia or leukocytosis, anaemia, a raised anion gap and the presence of an underlying malignancy.