Role of pleural fluid interleukin-6, neutrophil-lymphocyte ratio, and monocyte-lymphocyte ratio in distinguishing tuberculous and malignant pleural effusions

Abstract

Background: Pleural effusion is caused by various disease, including tuberculosis infection and malignancy. To determine the etiology, immunologic parameters are needed to distinguish tuberculous and malignant pleural effusions, including pleural fluid interleukin-6 (IL-6), neutrophil-lymphocyte ratio (NLR), and monocyte-lymphocyte ratio (MLR).Methods: This was a cross-sectional study, conducted at Sanglah General Hospital in Denpasar from March 2020 to September 2020. Pleural fluid IL-6 and leucocyte differential count were measured from subjects with tuberculous and malignant pleural effusions.Results: There were 22 tuberculous pleural effusion subjects with mean pleural fluid IL-6 9269.017±902.211 pg/ml, median (range) pleural fluid NLR 0.123 (0.044-9.449), and MLR 0.065 (0.044-0.355). There were 31 subjects with malignant pleural effusions, with mean pleural fluid IL-6 8212.146±2022.350 pg/ml, median pleural fluid NLR 0.189 (0.015-2.599), and MLR 0.065 (0.010-0.254). Pleural fluid IL-6 in tuberculous pleural effusions were significantly higher (p=0.014). With a pleural fluid IL-6 cut-off ≥9147.959 pg/ml, sensitivity of 63.6% and specificity of 64.5% were obtained. Pleural fluid NLR and MLR of the two groups were not significantly different (p=0.807 and p=0.116).Conclusions: Pleural fluid IL-6 in tuberculous pleural effusions is higher than malignant pleural effusions, with a cut-off of ≥9147.959 pg/ml, tuberculous pleural effusions can be diagnosed with sensitivity of 63.6% and specificity of 64.5%. There is no difference in pleural fluid NLR and MLR in tuberculous and malignant pleural effusions.

Comparison between serum pleural effusion albumin gradient, total protein, lactate dehydrogenase, and erythrocyte count in malignant and non-malignant pleural effusion

“…Singgih et al, reported a similar result, 61.3% of the subject of MPE was female and the mean age of the MPE subject was 71±8.38 years old. 7 There was a substantial number of female subjects with breast, ovarium, and cervix uteri cancer in this study, which could explain this result. According to Deniz et al, malignancy associated with pleural effusion usually occurs in patients older than 50 years old.…”

“…A study by Singgih et al, revealed no significant difference between MPE and tuberculous PE (1,037 (41-34,012) IU/L vs. 583.5 (189-11,469) IU/L; p=0.448). 7 However, Antonagelo et al, showed a significant difference between malignant and tuberculous PE (1,177±675 vs. 1,030±788 IU/L; p=0.003). 18 NMPE groups in our study consisted of exudate and transudate.…”