Early predictors of mortality in pneumococcal bacteraemia

Objectives: Pneumococcal bacteraemia carries a mortality of about 20%. Appr oximately 50% of deaths from pneumococcal bacteraemia occur within the firs t 48h of admission. In order to influence outcome, critically ill patients should be identified at the time of presentation. This study enables the cl inician to rapidly make an evidence-based assessment of a patient's prognos is, allowing the identification of patients who should be placed in a high- risk category at an early stage, when appropriate management is most likely to be effective. Methods: Data were collected from the medical record of history; physical e xamination, radiological examination and laboratory investigations done on initial presentation using a standardized proforma, The data were first exa mined by Pearson's Chi-squared test, with Yates' correction if needed. Vari ables found to be significantly associated with case fatality (P<0.05) by t hese methods were examined by stepwise logistic regression analysis in orde r to identify those factors which were independent predictors of case fatal ity: Results: The overall case fatality was 21%. Older age, apyrexia, tachypnoea , bilateral consolidation, hypoalbuminaemia, elevated aminotransferases, re nal impairment, acidosis and It leucopaenia were significantly associated w ith higher case fatality Older age, acidosis and elevated serum alanine ami notransferase (ALT) were independent predictors of case fatality: Fifty-fiv e percent of isolates belonged to serotypes 4 6B, 9V: 14, 19F and 23F, to w hich good antibody levels have been documented in both young and elderly pa tients post-vaccination. Serotype 14 was most common, and was significantly associated with higher case fatality Colder weather was associated with a higher incidence of both infection and case fatality The case fatality amon gst patients receiving ITU; management was 44%. Less than 50% of patients t wo died received ITU management. Conclusions: Despite the increased availability of new antibiotics and vacc ines, the mortality of patients with pneumococcal bacteraemia remains uncha nged. The parameters above allow early identification of patients with a hi gher case fatality; these patients may benefit from being placed in a "high -risk" category early on in their management. vaccination of the elderly ma y reduce the incidence and/or mortality from pneumococcal bacteraemia. Furt her studies are required to understand the reasons for referral for intensi ve therapy in acute pneumococcal bacteraemia and whether ITU management aff ects outcome. (C) 2000 The British Infection Society.