Morphological prognostic factors in nosocomial pneumonia: an autopsy study

Objective: To determine the prevalence of nosocomial pneumonia in autopsies at a public university hospital; to identify the risk factors for nosocomial pneumonia and the potential prognostic factors associated with fatal nosocomial pneumonia and with fatal aspiration pneumonia; and to determine whether anatomopathological findings correlate with nosocomial pneumonia or aspiration pneumonia. Methods: A retrospective study involving 199 autopsied patients, older than 1 year of age, who had been admitted to the Sao Paulo State University Botucatu School of Medicine Hospital das Clinicas and died of nosocomial pneumonia (underlying or contributing cause), between 1999 and 2006. Demographic, clinical and anatomopathological variables were tested regarding their association with the outcomes (fatal nosocomial pneumonia and fatal aspiration pneumonia). The significant variables were analyzed using multivariate analysis. Results: The mean age was 59 19 years. The prevalence of nosocomial pneumonia in autopsies was 29%, and the disease was the cause of death in 22.6% of the autopsied patients. Fatal nosocomial pneumonia correlated with the following anatomopathological findings: tobacco-associated structural lesions (OR = 3.23; 95% CI: 1.26-2.95; p = 0.02) and bilateral pneumonia (OR = 3.23; 95% CI: 1.26-8.30; p = 0.01). None of the variables were found to be significantly associated with fatal aspiration pneumonia. Conclusions: In our sample, there was a high prevalence of nosocomial pneumonia, which was responsible for almost 25% of all of the deaths. Smoking-related structural lesions and bilateral pneumonia all favored mortality. These findings corroborate the results of various clinical studies on nosocomial pneumonia.