Role of respiratory secretion culture in the surgical outcome prediction of bacterial empyema

Abstract

Objectives: Thoracic empyema is a serious infection. Video-assisted thoracoscopic surgery is a recommended treatment, and pleural fluid and tissue cultures are collected intraoperatively. The combination of a pleural peels tissue culture and a pleural fluid culture improves the positive culture rate. We aimed to investigate the role of respiratory secretion cultures to determine the optimal management for improving surgical outcome.

Methods: The study analyzed 225 adult patients with phase II/III thoracic empyema who underwent thoracoscopic decortication. Respiratory secretion cultures were obtained and compared with pleural cultures. Key outcomes were culture positivity and pathogen consistency, with secondary outcomes including intensive care unit stay, hospital stay, and mortality.

Results: There were 225 empyema patients with either a positive pleural fluid culture or a positive pleural peel tissue culture. Of these, 76 patients had positive respiratory secretion culture findings during hospitalization. The most common pathogen species were Pseudomonas aeruginosa (44%) and Klebsiella pneumoniae (16%) in the respiratory secretion cultures and Streptococcus spp. (38%) and Klebsiella pneumoniae (12%) in the pleural cultures. There were 30 patients having a common pathogen in the respiratory secretion culture and in the pleural fluid/tissue culture. Poor outcome measures were found in these patients, including the longer use of antibiotics preoperatively [2.50 (1.00-6.00) days versus 5.00 (2.75-11.00) days, p = 0.006] and a higher mortality rate during hospitalization (40.0% versus 17.4%, p = 0.002).

Conclusions: Respiratory secretion cultures are vital for predicting surgical outcomes in bacterial empyema, and prompt specimen collection can improve patient survival.

Keywords: Bacterial empyema; Pleural effusion culture; Pleural tissue culture; Respiratory secretion culture; Surgical outcome.

Fig. 1

Positive culture rate by quantity of respiratory secretion cultures

Fig. 2

Positive culture rate by method of obtaining respiratory secretion specimens

Fig. 3

Pathogen distributions. Pseudomonas aeruginosa (44%), Klebsiella pneumoniae (16%), and Staphylococcus aureus (10%) were the most common pathogen species in the respiratory secretion cultures (blue bars). Streptococcus spp. (38%), Klebsiella pneumoniae (12%), and Staphylococcus aureus (11%) were the most common pathogen species in pleural effusion/tissue cultures (orange bars)