https://doi.org/10.4081/monaldi.2025.3060

Diagnostic value of pleural fluid and serum C-reactive protein/albumin ratio in exudate/transudate, infectious/non-infectious pleural fluid discrimination

Early Access
Submitted: May 21, 2024
Accepted: February 24, 2025
Published: March 26, 2025
Pleural fluid, exudate, transudate, CRP/albumin ratio
Abstract Views: 107
PDF_EARLY VIEW: 59
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Authors

Ayshan Mammadova
aysenmammadova665@gmail.com
https://orcid.org/0000-0002-8838-7419
Department of Chest Diseases, Medical Faculty, Gazi University, Ankara, Turkey.
Zuleyha Galata
https://orcid.org/0000-0001-9627-4281
Department of Chest Diseases, Medical Faculty, Gazi University, Ankara, Turkey.
Zeynep Yaylçınkaya
Afyonkarahisar Central Community Health Center, Afyon, Turkey.
Nilgun Yılmaz Demirci
Department of Chest Diseases, Medical Faculty, Gazi University, Ankara, Turkey.

As a new parameter, the C-reactive protein (CRP)/albumin ratio (CAR) has been shown to be more accurate than CRP and albumin alone in predicting the diagnosis and overall prognosis in cancer, sepsis, and vascular and non-vascular conditions. In this direction, we aimed to investigate the role of CAR in the differentiation of transudate/exudate and infectious/non-infectious in our study. A total of 160 patients who were examined for pleural fluid between August 2020 and February 2021 were included in our single-center prospective observational study. The study did not include those who could not undergo diagnostic thoracentesis and those under the age of 18. The presence of pleural effusion was determined by physical and radiological examinations [chest radiograph, thorax computed tomography, thoracic ultrasonography (US)]. Diagnostic thoracentesis was performed under the guidance of thoracic US after the patients who met the inclusion criteria signed an informed consent form. A total of 160 patients, 117 (73.1%) male and 43 (26.9%) female, were included in the study. While exudate was detected in 101 (63.1%) cases and transudate was detected in 59 (36.9%) cases, 47 (29.4%) of these were due to infectious and 113 (70.6%) non-infectious causes. The mean pleural fluid CAR (46.38) and serum CAR (72.43) in the infectious group were found to be significantly higher than those in the non-infectious group (13.17 and 19.48, respectively) (p<0.001). The pleural fluid and serum CAR (31.79 and 49.68) were found to be significantly higher in the exudate-qualified group compared to the transudate-qualified group (7.76 and 9.97) (p<0.001). When the threshold value for the pleural fluid CAR is >15.65, it is 80.9% sensitive and 73.5% specific in predicting infectious fluid; when the threshold value was >9.48, it was found to be 71.3% sensitive and 71.2% specific in exudate-transudate discrimination. In conclusion, in our study, we see that the pleural fluid and serum CAR are promising parameters in the differentiation of infectious/non-infectious pleural effusions and in the differentiation of exudate/transudate.

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Scopus
Google Scholar
Europe PMC
Zocchi L. Physiology and pathophysiology of pleural fluid turnover. Eur Respir J 2002;20:1545-58. DOI: https://doi.org/10.1183/09031936.02.00062102
Tokgöz F, Gökşenoğlu N, Bodur Y, et al. Retrospective analysis of 240 cases with pleural effusion. Eurasian J Pulmonol 2014;16:78-83. DOI: https://doi.org/10.5152/ejp.2014.02779
Zhang X, Wang A, Zhang J, et al. Association of plasma C-reactive protein with ischaemic stroke: a Mendelian randomization study. Eur J Neurol 2020;27:565-71. DOI: https://doi.org/10.1111/ene.14113
Cayir S, Hizli O, Kayabasi S. Is C-reactive protein to albumin ratio an indicator of poor prognosis in Bell's palsy? Eur Arch Otorhinolaryngol 2020;277:115-9. DOI: https://doi.org/10.1007/s00405-019-05691-3
Liu Z, Jin K, Guo M, et al. Prognostic value of the CRP/Alb Ratio, a novel Inflammation-based score in pancreatic cancer. Ann Surg Oncol 2017;24:561-8. DOI: https://doi.org/10.1245/s10434-016-5579-3
Zhou T, Zhan J, Hong S, et al. Ratio of C-reactive protein/albumin is an inflammatory prognostic score for predicting overall survival of patients with small-cell lung cancer. Sci Rep 2015;5:10481. DOI: https://doi.org/10.1038/srep10481
Esper DH, Harb WA. The cancer cachexia syndrome: a review of metabolic and clinical manifestations. Nutr Clin Pract 2005;20:369-76. DOI: https://doi.org/10.1177/0115426505020004369
Gibson DJ, Hartery K, Doherty J, et al. CRP/albumin ratio: an early predictor of steroid responsiveness in acute severe ulcerative colitis. J Clin Gastroenterol 2018;52:e48-52. DOI: https://doi.org/10.1097/MCG.0000000000000884
Wang R, He M, Ou X, et al. CRP Albumin ratio is positively associated with poor outcome in patients with traumatic brain injury. Clin Neurol Neurosurg 2020;195:106051. DOI: https://doi.org/10.1016/j.clineuro.2020.106051
Hizli O, Cayir S, Coluk Y, et al. The novel indicators of moderate to severe sleep apnea: fibrinogen to albumin ratio vs. CRP to albumin ratio. Eur Arch Otorhinolaryngol 2021;278:851-5. DOI: https://doi.org/10.1007/s00405-019-05770-5
Dietrich CF, Mathis G, Cui XW, et al. Ultrasound of the pleurae and lungs. Ultrasound Med Biol 2015;41:351-65. DOI: https://doi.org/10.1016/j.ultrasmedbio.2014.10.002
Light RW, Macgregor MI, Luchsinger PC, Ball WC Jr. Pleural effusions: the diagnostic separation of transudates and exudates. Ann Intern Med 1972;77:507-13. DOI: https://doi.org/10.7326/0003-4819-77-4-507
Ak G, Metintas S, Taskın AN, et al. Evaluation of exudative pleural effusions: a multicenter, prospective, observational study. Lung 2022;200:807-15. DOI: https://doi.org/10.1007/s00408-022-00573-8
Marel M. Epidemiology of pleural effusion. Eur Respir Mon 2002;22:146-56.
Arakawa Y, Miyazaki K, Yoshikawa M, et al. Value of the CRP-albumin ratio in patients with resectable pancreatic cancer. J Med Invest 2021;68:244-55. DOI: https://doi.org/10.2152/jmi.68.244
Komura N, Mabuchi S, Shimura K, et al. Significance of pretreatment C-reactive protein, albumin, and C-reactive protein to albumin ratio in predicting poor prognosis in epithelial ovarian cancer patients. Nutr Cancer 2021;73:1357-64. DOI: https://doi.org/10.1080/01635581.2020.1798479
Ni XF, Wu J, Ji M, et al. Effect of C-reactive protein/albumin ratio on prognosis in advanced non-small-cell lung cancer. Asia Pac J Clin Oncol 2018;14:402-9. DOI: https://doi.org/10.1111/ajco.13055
Kalabin A, Mani VR, Valdivieso SC, Donaldson B. Does C reactive protein/albumin ratio have prognostic value in patients with COVID-19? J Infect Dev Ctries 2021;15:1086-93. DOI: https://doi.org/10.3855/jidc.14826
Watanabe N, Ishii T, Kita N, et al. The usefulness of pleural fluid presepsin, C-reactive protein, and procalcitonin in distinguishing different causes of pleural effusions. BMC Pulm Med 2018;18:176. DOI: https://doi.org/10.1186/s12890-018-0740-3
San José ME, Valdés L, Vizcaíno LH, et al. Procalcitonin, C-reactive protein, and cell counts in the diagnosis of parapneumonic pleural effusions. J Investig Med 2010;58:971-6. DOI: https://doi.org/10.2310/JIM.0b013e3181f88648
Ahmed MM, Abdelhalim HA, El Kholy NA. Cut-off value of pleural fluid C-reactive protein in etiologic diagnosis of pleural fluid. Egypt J Chest Dis Tuberc 2014;63:617-23. DOI: https://doi.org/10.1016/j.ejcdt.2014.03.012
Don BR, Kaysen G. Serum albumin: relationship to inflammation and nutrition. Semin Dial 2004;17:432-7. DOI: https://doi.org/10.1111/j.0894-0959.2004.17603.x
Barbosa-Silva MC, Barros AJ, Wang J, et al. Bioelectrical impedance analysis: population reference values for phase angle by age and sex. Am J Clin Nutr 2003;77:412-6.
Jeejeebhoy KN. Clinical nutrition: 2. Protein metabolism in stress and injury. CMAJ 2000;163:849-53.
Karabağ Y, Çağdaş M, Rencuzogullari I, et al. Relationship between C-reactive protein/albumin ratio and coronary artery disease severity in patients with stable angina pectoris. J Clin Lab Anal 2018;32:e22457. DOI: https://doi.org/10.1002/jcla.22457
Özcan S, Dönmez E, Yavuz Tuğrul S, et al. The prognostic value of C-reactive protein/albumin ratio in acute pulmonary embolism. Rev Invest Clin 2022;74:097-103. DOI: https://doi.org/10.24875/RIC.21000547

Ethics Approval

This prospective and single-center study was conducted with the approval of the Ankara City Hospital Faculty of Medicine Clinical Research Ethics Committee (date: 16.07.2020; decision no.: E1-20-918).

How to Cite

Mammadova, Ayshan, Zuleyha Galata, Zeynep Yaylçınkaya, and Nilgun Yılmaz Demirci. 2025. “Diagnostic Value of Pleural Fluid and Serum C-Reactive Protein Albumin Ratio in Exudate Transudate, Infectious Non-Infectious Pleural Fluid Discrimination”. Monaldi Archives for Chest Disease, March. https://doi.org/10.4081/monaldi.2025.3060.
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