Investigating the role of serum and pleural fluid calprotectin and myeloperoxidase in pleural infection and empyema

Overview

Pleural infection is a common and severe condition in which fluid builds up between the lungs and the chest due to a bacterial infection. Pleural infections, cause prolonged hospital admissions, and are frequently fatal. Management of pleural infections requires prolonged antibiotic treatment and drainage of infected pleural fluid. ^{1, 2} The PEACE Study (Parapneumonic effusion and Empyema: Aetiology and Clinical outcome Evaluation in Canterbury) is a prospective cohort study of patients with pleural infection (n=86), with comprehensive data on aetiology and clinical outcomes, in addition to pleural fluid and blood fractions available for measurement of biomarkers.

Neutrophils play a key role as the body manages pleural infection, but early in an infection, neutrophils also may contribute to fluid accumulation and bacterial translocation to the space by increasing pleural permeability. ³ Currently sampling of pleural fluid using thoracentesis is an essential step to assess pH and glucose concentrations to whether pleural infection can be classified as simple or complex, determining management. However, thoracentesis – puncturing the pleural space via the chest wall – carries risk of complication, and comparable biomarkers assessable via blood testing would be a significant advance.

Calprotectin and myeloperoxidase are proteins that are secreted by neutrophils during inflammation provide a defence against invading pathogens. Measurement of calprotectin has been used to guide treatment in inflammatory diseases such as Crohn’s disease. ^{4, 5} Limited existing data suggests pleural fluid calprotectin and myeloperoxidase may be able to distinguish complex from simple pleural infections, ^{6, 7} and pilot analyses from the PEACE study (which are ongoing), also show a broad gradient of calprotectin and myeloperoxidase concentrations suggesting utility.

Important next steps, that would form the basis of a BBioMed(Hons) project would be to to test the hypotheses that plasma calprotectin will be closely correlated to pleural fluid calprotectin, and to evaluate assays that might be suitable for clinical use.

References

1: Davies HE, Davies RJ, Davies CW, Group BTSPDG. Management of pleural infection in adults: British Thoracic Society Pleural Disease Guideline 2010. Thorax. 2010; 65 Suppl 2: ii41-53.
2: Shen KR, Bribriesco A, Crabtree T, Denlinger C, Eby J, Eiken P, Jones DR, Keshavjee S, Maldonado F, Paul S, Kozower B. The American Association for Thoracic Surgery consensus guidelines for the management of empyema. The Journal of thoracic and cardiovascular surgery. 2017; 153: e129-e46.
3: Corcoran JP, Wrightson JM, Belcher E, DeCamp MM, Feller-Kopman D, Rahman NM. Pleural infection: past, present, and future directions. Lancet Resp Med. 2015; 3: 563-77.
4: Kalla R, Kennedy NA, Ventham NT, Boyapati RK, Adams AT, Nimmo ER, Visconti MR, Drummond H, Ho G-T, Pattenden RJ. Serum calprotectin: A novel diagnostic and prognostic marker in inflammatory bowel diseases. Am J Gastro. 2016; 111: 1796-805.
5: Khaki-Khatibi F, Qujeq D, Kashifard M, Moein S, Maniati M, Vaghari-Tabari M. Calprotectin in inflammatory bowel disease. Clinica Chimica Acta. 2020; 510: 556-65.
6: Wu K-A, Wu C-C, Liu Y-C, Hsueh P-C, Chin C-Y, Wang C-L, Chu C-M, Shih L-J, Yang C-Y. Combined serum biomarkers in the noninvasive diagnosis of complicated parapneumonic effusions and empyema. BMC Pulm Med. 2019; 19: 108.
7: Alegre J, Jufresa J, Segura R, Ferrer A, Armadans L, Aleman C, Marti R, Ruiz E, Fernández de Sevilla T. Pleural-fluid myeloperoxidase in complicated and noncomplicated parapneumonic pleural effusions. Eur Respir J. 2002; 19: 320-5.

Preferred student expertise

Students with strong laboratory skills, an inquisitive mind and analytical thinking.

This is one of a number of projects on offer for the next intake of BBiomedSc(Hons) at the University of Otago, Christchurch campus.

Useful information

• Graduate research at the University of Otago
• Scholarships at the University of Otago

Additional information

• University of Otago, Christchurch, BBiomedSc(Hons)
• Dr Michael Maze’s profile page
• The Infection Group
• Mātai Hāora – Centre for Redox Biology and Medicine
• Department of Pathology and Biomedical Science