Abstract
Background: Bacterial pleural infection has been a substantial clinical challenge since ancient times. Identification of the infecting bacteria by culture of pleural fluid is of great importance for clinical care. Inoculating pleural fluid into blood culture bottles at the bedside can potentially improve the yield of pleural fluid culture.
This study was done to assess whether addition of blood culture bottle sample to the standard bottle sample increases the rate of detection in pleural fluid culture for the evaluation of empyema.
Materials and Methods: A cross sectional observational study was conducted in patients with clinical presentation compatible with empyema with purulent pleural fluid drainage during thoracocentesis for a period of 1 year from 1st January 2013 to 31st December. Those having sputum positive tuberculosis were excluded. Two samples were collected in sterile bottle for standard culture and one sample in blood culture bottle from every patient enrolled into the study. The second standard culture was taken to assess whether the increase in yield was due to repetition of culture. All samples sent to microbiology laboratory of same institute. The standard bottle samples were subjected to Gram staining and inoculated to blood, MacConkey and chocolate agar. Blood culture bottle containing pleural fluid was incubated at 370 c for upto 7 days. A Gram stain was performed on any positive bottle and subculture was done to identify the organism. Identification of cultures were done by standard biochemical tests in microbiology laboratory. Further evaluation and management of patients done according to the department protocol
Results: A total of 60 patients were enrolled in the study.The standard laboratory culture of pleural fluid was positive in 19 (31.6%) cases. A second standard culture did not produce an increase in bacterial yield. Pleural fluid culture in blood culture bottle was positive in 24 (40%) cases. Addition of blood culture bottle culture to standard laboratory culture increased culture positivity by 8.4 (chi square value 41.7 with p <0.001). All cases which are culture positive in standard bottle were also positive in blood culture bottle. Klebsiella pneumoniae was the most common bacterium identified in pleural fluid culture. Blood culture bottle culture identified two extra cases of Pseudomonas aeruginosa, one case of Escherichia coli and Klebsiella pneumoniae, and a mixed infection case
Conclusion: Inoculating pleural fluid into blood culture bottles at the bedside increases the rate of bacterial pathogen identification in empyema, when compared to standard laboratory culture.
Keywords: Empyema, Blood culture bottle, Standard laboratory culture.
References
- Light RW, Girard WM, Jenkinson SG, et al. Parapneumonic effusions. Am J Med 1980; 69:507-12.
- Maskell NA, Davies CW, Nunn AJ, et al. UK controlled trial of intrapleural streptokinase for pleural infection. N Engl J Med 2005;352:865-74.
- Finley C, Clifton J, Fitzgerald JM, et al. Empyema: an increasing concern in Canada.Can Respir J 2008;15:85-9.
- Light RW: Parapneumonic effusions and empyema. Proc Am Thorac Soc 2006;3: 75-80.
- Chapman SJ, Davies RJ: Recent advances in parapneumonic effusions and empyema. Curr Opin Pulm Med 2004;10:299–304.
- Good JT Jr, Taryle DA, Maulitz RM, et al. The diagnostic value of pleural fluid pH.Chest 1980;78:55-59.
- Bartlett JG. Anaerobic bacterial infections of the lung and pleural space. Clin Infect Dis 1993;16( 4):248-55.
- Ahmed RA, Marrie TJ, Huang JQ. Thoracic empyema in patients with community-acquired pneumonia. Am J Med,2006;119(10): 877-83.
- Schultz KD, Fan LL, Pinsky J, et al. The changing face of pleural empyemas in children: epidemiology and management. Pediatrics, 2004;113(6):1735-40.
- Light RW. Diagnostic principles in pleural disease. Eur Respir J 1997;10:475-81.
- Davies CW, Gleeson FV, Davies RJ; on behalf of the BTS Pleural Disease Group,a subgroup of the BTS Standards of Care Committee. BTS guidelines for the management of pleural infection. Thorax 2003;58(Suppl II):18-28.
- Ferrer A, Osset J, Alegre J, et al. Prospective clinical and microbiological study of pleural effusions. Eur J Clin Microbiol Infect Dis 1999;18:237-41.
- Alados JC, Gutierrez J, Roman J, et al. Utilidad del frasco de hemocultivo para aislamientos de microorganismos a partir de liquidos asciticos y pleurales. Revista Espanola de Microbiologia Clinica 1990;5:148-51.
- Bourbeau P, Riley J, Heiter BJ, et al. Use of the BacT/Alert blood culture system for culture of sterile body fluids other then blood. J Clin Microbiol 1998;36:3273-7.
- Akcam FZ, Yayli G, Uskun E, et al. Evaluation of the Bactec microbial detection system for culturing miscellaneous sterile body fluids. Res Microbiol 2006;157:433-6.
- Fuller DD, Davis TE, Kibsey PC, et al. Comparison of BACTEC Plus 26 and 27 media with and without fastidious organism supplement with conventional methods for culture of sterile body fluids. J Clin Microbiol 1994;32:1488-92.
- Azap OK, Timurkaynak F, Sezer S, et al. Value of automatized blood culture systems in the diagnosis of continuous ambulatory peritoneal dialysis peritonitis. Transplant Proc 2006;38:411-12.
- Bobadilla M, Sifuentes J, Garcia-Tsao G. Improved method for the bacteriological diagnosis of spontaneous bacterial periton-itis. J Clin Microbiol 1989;27:2145-7.
- Von Essen R, Holtta A. Improved method of isolating bacteria from joint fluids by the use of blood culture bottles. Ann Rheum Dis 1986;45:454-7.
- Sarah M Menzies,Najib M Rahman,John M Wrightson,et al.Blood culture bottle culture of pleural fluid in pleural infection. Thorax 2011;66:658-662.
- Lin YC, Tu CY, Chen W, et al. An urgent problem of aerobic gramnegative pathogen infection in complicated parapneumonic effusions or empyemas. Intern Med, 2007;46(15): 1173-8.
- Ramana BV, Abhijit Chaudhury, M.Bhagyalakshmi, et al.Bacteriology of pleural fluid infections at a tertiary care hospital.IJPRBS 2012;1:373-79.
Corresponding Author
Thomas George Puthusseril
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DOI: https://dx.doi.org/10.18535/jmscr/v5i8.148
