Community-acquired pneumonia of diverse aetiology: prognostic features in patients admitted to an intensive care unit and a "severity of illness" core.

In a retrospective study of 73 patients with community-acquired lobar pneumonia of diverse aetiology admitted to an intensive care unit, an attempt was made to identify those factors among the demographic and clinical features and results of initial laboratory investigations that were predictive of the ultimate outcome. A lower mean white cell count (p = 0.03), platelet count (p = 0.02), total serum protein (p = 0.005) and albumin (p = 0.02) and a higher mean serum creatinine (p = 0.03) and phosphate level (p = 0.02) appeared to be predictive of a poor prognosis. The most significant variable predictive of mortality, was the presence of bacteraemia (p = 0.0005). Severity of illness scoring systems by omitting microbiological data appear to underestimate predicted patient mortality. The mortality rate of critically ill patients with community-acquired lobar pneumonia remains high, despite advances in antimicrobial chemotherapy and intensive care unit facilities, particularly in the presence of certain negative prognostic factors of which the presence of bacteraemia is the most important.