Predictive Model for Discrimination of Tuberculous Pleural Effusion From Severe Mycoplasma pneumoniae Pneumonic Effusion in Children

Mycoplasma pneumoniae Pleural Effusion in Adults

Parapneumonic effusions often complicate Mycoplasma pneumoniae (MP) pneumonia, contrary to the notion that they are a rare feature of MP infection. Increased research and evidence on MP parapneumonic effusions (MPPE) can help elucidate its clinical significance as one of the variable manifestations of MP infection. This article aims to summarize the existing literature about the clinical characteristics of MPPE in adults and discuss its diagnostic implications from the perspective of pleural fluid analysis. Approximately 20–25% of adult patients with MP pneumonia develop MPPE, and its frequency in children and adults seems to be similar. Although the pathogenesis of MPPE remains to be elucidated, MP-induced cell-mediated immune mechanisms might be partially associated with the development of MPPE. MPPE usually shows mononuclear leukocyte predominance with elevated adenosine deaminase (ADA) activity, similar to tuberculous pleural effusion (TPE). The degree of increase in pleural fluid ADA levels and serum inflammatory biomarkers may help differentiate between MPPE and TPE. During the acute phase, a single positive IgM and positive polymerase chain reaction results allow for a precise and reliable MP infection diagnosis. The mainstay of treatment is the selection of adequate anti-mycoplasma antibiotics with or without corticosteroid, based on the local epidemiologic data on macrolide resistance.

The value of interleukin-27 for differentiating tuberculous pleural effusion from Mycoplasma pneumoniae pneumonic effusion in children

OBJECTIVES

The early diagnosis of tuberculous pleural effusion (TPE) is challenging due to the difficulty of isolating Mycobacterium tuberculosis, and pleural biomarkers are an optional choice. Recent studies showed that interleukin-27 (IL-27) appears to be a new accurate biomarker for TPE in adults and no related studies were reported in children. In this study, we aimed to evaluate the potential value of IL-27 in pediatric tuberculous pleurisy by detecting its levels in pleural fluid and serum.

METHODS

A total of 48 children with TPE and 64 children with severe Mycoplasma pneumoniae (MP) pneumonic effusion (SMPPE) were enrolled in this study. IL-27 concentrations were measured in serum and pleural fluid. The diagnostic yield of IL-27 was evaluated using receiver operating characteristic (ROC) curves.

RESULTS

The level of p-IL-27 in TPE showed statistically no significant difference when compared with SMPPE (p > 0.05). However, pleural fluid IL-27 (p-IL-27) / serum IL-27 (s-IL-27) ratio in TPE were significantly much higher than those in SMPPE (p < 0.05). By the analysis of the ROC curves, the diagnostic sensitivity and specificity of the p-IL-27/s-IL-27 ratio were 100% and 48.44%, respectively (cutoff value of 1.0280). The area under the ROC curve for p-IL-27/s-IL-27 was 0.7295.

CONCLUSION

Pleural fluid IL-27 alone was not accurate in distinguishing pediatric TPE from SMPPE, which was different from the diagnostic value of IL-27 in adult studies due to the different disease spectra between children and adults. Our results implied that the p-IL-27/s-IL-27 ratio had a potential value in distinguishing TPE from SMPPE. However, the specificity of IL-27 was relatively lower and it is necessary to find a more specific marker in tuberculous pleurisy of children.