An independent prognostic factor in surgical cases of pleural empyema caused by common bacteria is the presence of a fistula

Objectives Some surgical cases of pleural empyema lead to death despite multidisciplinary treatment. The purpose of this study was to identify prognostic factors in cases treated surgically for pneumonia-associated pleural effusions and empyema caused by common bacteria. Methods We conducted a retrospective cohort study of 108 surgical patients of empyema who encountered at our hospital between 2011 and 2021. Patients were divided into surviving and non-surviving cases. Factors on admission (age, sex, body mass index, presence of fistula, performance status, pleural fluid culture results, HbA1c, albumin, leukocytes, hemoglobin, body temperature, heart rate, respiratory rate, systolic blood pressure, prognostic nutritional index, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and RAPID score) were compared between the two groups. Results There were 87 cases of pleural empyema caused by pneumonia due to common bacteria. Variables that differed significantly in univariate analysis between the surviving and non-surviving cases in patients’ characteristics on admission were fistula ( p value < 0.001, odds ratio 20.000, 95% confidence interval 3.478–115.022), positive pleural fluid culture (0.016, 6.591, 1.190–36.502), body mass index < 18.5 (0.001, 16.857, 1.915–148.349), performance status 0–1 (0.007, 11.778, 1.349–102.858), and hemoglobin (0.024, 1.768, 1.077–2.904). Multivariate analysis showed significant differences in the presence of fistula ( p = 0.036, CI 1.174–125.825). The odds ratio was 12.154. The mortality rate was 3.8% for non-fistulous empyema and 44.4% for fistulous empyema. In 6 of 9 cases of fistulous empyema, the fistula could be closed. Conclusion Fistula was a significant independent prognostic factor for pneumonia-associated pleural effusions and empyema caused by common bacteria.