Myeloid-derived suppressor cells in pleural effusion as a diagnostic marker for early discrimination of pulmonary tuberculosis from pneumonia.

Introduction: Tuberculous pleural effusion (TPE) stands as one of the primary forms of extrapulmonary tuberculosis (TB) and frequently manifests in regions with a high prevalence of TB, consequently being a notable cause of pleural effusion in such areas. However, the differentiation between TPE and parapneumonic pleural effusion (PPE) presents diagnostic complexities. This study aimed to evaluate the potential of myeloid-derived suppressor cells (MDSCs) in the pleural fluid as a potential diagnostic marker for distinguishing between TPE and PPE. Methods: Adult patients, aged 18 years or older, who presented to the emergency room of a tertiary referral hospital and received a first-time diagnosis of pleural effusion, were prospectively enrolled in the study. Various immune cell populations, including T cells, B cells, natural killer (NK) cells, and MDSCs, were analyzed in both pleural fluid and peripheral blood samples. Results: In pleural fluid, the frequency of lymphocytes, including T, B, and NK cells, was notably higher in TPE compared to PPE. Conversely, the frequency of polymorphonuclear (PMN)-MDSCs was significantly higher in PPE. Notably, compared to traditional markers such as the neutrophil-to-lymphocyte ratio and adenosine deaminase level, the frequency of PMN-MDSCs emerged as a more effective discriminator between PPE and TPE. PMN-MDSCs demonstrated superior positive and negative predictive values and exhibited a higher area under the curve in the receiver operating characteristic curve analysis. PMN-MDSCs in pleural effusion increased the levels of reactive oxygen species and suppressed the production of interferon-gamma from T cells following nonspecific stimulation. These findings suggest that MDSC-mediated immune suppression may contribute to the pathology of both TPE and PPE. Discussion: The frequency of PMN-MDSCs in pleural fluid is a clinically useful indicator for distinguishing between TPE and PPE.

Pleural Effusion Caused by an Unusual Mass in the Right Hemithorax.

CASE PRESENTATION: An 80-year-old woman presented with complaints of weakness and dizziness. She had a medical history of subacute cerebral ischemia, vertigo, hypertension, and thalassemia minor. The patient was born and raised in Turkey and has lived in Switzerland for 50 years. Her sister died of a mesothelioma caused by asbestos exposure at the age of 60 years but had lived in Turkey until her death. The patient had neither a history of TB nor B symptoms. She has never smoked.

[Endometriosis-related recurrent unilateral hemorrhagic pleural effusion: a case report].

Hemorrhagic pleural effusion (PE) is common in clinical practice. According to the guidelines, the etiological diagnosis of PE should focus on the identification of common diseases. In most cases, the etiology of PE can be determined by clinical history, physical examination, laboratory and imaging examinations, and pleural biopsy or video-assisted thoracic surgery (VAST). We reported a rare case of a 32-year-old woman with recurrent unilateral hemorrhagic pleural effusion (highly correlated with menstrual cycle) and chest pain that was diagnosed as thoracic endometriosis syndrome (TES) by pathological biopsy and immunohistochemistry. Later she underwent surgery combined with hormone therapy. During the follow-up, the right PE decreased, and she had no chest pain. Therefore, women of reproductive age with regular unilateral bloody pleural effusions should be alert to TES.

Performance of CBNAAT on Pleural Biopsies Obtained by Semirigid Thoracoscopy for Diagnosis of Unexplained Pleural Effusion: A Prospective Study from North India.

BACKGROUND: Exudative pleural effusions are commonly encountered in clinical practice, but in about one-fourth of cases, etiology remains elusive after initial evaluation. Medical thoracoscopy with semirigid thoracoscope is a minimally invasive procedure with high diagnostic yield for diagnosing pleural diseases, especially these undiagnosed exudative pleural effusions. In tubercular endemic areas, often, these effusions turn out to be tubercular, but the diagnosis of tubercular pleural effusion is quite challenging due to the paucibacillary nature of the disease. Although culture is the gold standard, it is time-consuming. Cartridge-based nucleic acid amplification test (CBNAAT) is a novel rapid diagnostic test for tuberculosis (TB) and has been recommended as the initial diagnostic test in patients suspected of having extrapulmonary TB (EPTB). MATERIALS AND METHODS: We conducted a prospective observational study of 50 patients with undiagnosed pleural effusion admitted to our tertiary care hospital. The primary aim of the study is to evaluate the diagnostic performance of CBNAAT on thoracoscopic guided pleural biopsy and compare it with conventional diagnostic techniques like histopathology and conventional culture. RESULTS: Of 50 undiagnosed pleural effusions, TB (50%) was the most common etiology. The overall diagnostic yield of semirigid thoracoscopy in this study was 74%. Our study showed that CBNAAT of pleural biopsies had a sensitivity of 36% only but a specificity of 100%. The sensitivity of CBNAAT was not far superior to the conventional culture. CONCLUSION: Tuberculosis (TB) is a common cause of undiagnosed pleural effusion in our set-up. CBNAAT testing of pleural biopsy, though, is a poor rule-out test for pleural TB, but it may aid in the early diagnosis of such patients.

Case Report: Toxocariasis Manifesting as Eosinophilic Pleural Effusion.

Toxocariasis is a prevalent zoonosis caused by infection with the larvae of Toxocara canis or Toxocara cati. It ranges in severity from mundane to life-threatening, depending on organ involvement. The lungs are often affected, manifesting as coughing, wheezing, and chest pain. However, pleural effusions rarely occur in patients with pulmonary toxocariasis. We report the case of a 74-year-old man with highly suspected toxocariasis who presented with an eosinophilic pleural effusion and eosinophilia. He developed dyspnea and a right-sided pleural effusion. Thoracentesis revealed an exudative effusion containing numerous eosinophils. The pleural effusion continued to increase, and the eosinophilia rapidly progressed. Although the patient had not recently had contact with animals or known exposure to contaminated food, water, or soil, toxocariasis was confirmed by positive serological test results for anti-Toxocara antibodies in the serum and pleural effusion. The patient was cured with albendazole treatment for 28 days. The pleural effusion and eosinophilia resolved and did not recur. Clinicians should consider toxocariasis in the differential diagnosis of patients presenting with eosinophilic pleural effusions.

Myelomatous pleural effusion in multiple myeloma- A rare presentation.

Multiple myeloma is a malignant plasma cell condition that mostly affects the skeletal system and bone marrow. Pleural effusions are uncommon and typically result from other conditions coexisting with multiple myeloma. Malignant myelomatous pleural effusions are rare complications of multiple myeloma, occurring in less than 1% of patients and are associated with poor prognosis having mean survival of less than 4 months. The present case report is a 41-year-old multiple myeloma patient who developed bilateral pleural effusion at a disease relapse. Chemotherapeutic regimen of cyclophosphamide, bortezomib, and dexamethasone given. Despite a positive response to treatment, the patient's condition worsened over the course of following month and he eventually passed away. Myelomatous pleural effusion indicates poor prognosis and early consideration helps in quick diagnosis and initiation of treatment which may help in improving prognosis.

Performance evaluation of a Test&Treat rapid detection kit for the diagnosis of septic effusions in dogs and cats.

OBJECTIVE: To evaluate the sensitivity and specificity of a veterinary point-of-care (POC) luminometer-based kit for the diagnosis of septic peritoneal or pleural effusion in dogs and cats. DESIGN: Prospective study performed between January 2020 and July 2021. SETTING: University teaching hospital. ANIMALS: Forty-eight animals with naturally occurring peritoneal or pleural effusion collected by aseptic abdominocentesis or thoracocentesis. PROCEDURES: Effusion samples were split into filtered (using a 10-micron filter) and unfiltered aliquots and analyzed by the POC instrument according to the manufacturer's instructions and following variable incubation periods. Samples were also plated aerobically on standard and blood agar plates. Proprietary reagents were added to samples, causing bacterial ATP to generate bioluminescence that is detected by the luminometer. Bioluminescence values (relative light units [RLUs]) were recorded and compared with the presence of bacterial growth on the culture plates. Nucleated cell counts in native and filtered effusion samples were recorded. RESULTS: Twenty-one samples were septic based on positive culture. RLUs were higher in septic effusions for filtered and native effusions compared with sterile effusions. The use of a filter reduced cell counts. In filtered samples incubated for 30 minutes before testing, the sensitivity and specificity of the luminometer for diagnosis of infection in cavitary effusions were 81% and 82%, respectively, using a cutoff of 12,202 RLUs. CONCLUSIONS: The luminometer kit evaluated in this study represents a viable screening tool for diagnosis of septic cavitary effusions and could be used in conjunction with other POC diagnostics to support the rapid diagnosis of infection.

Establishment and validation of a predictive nomogram for severe pleural effusion in liver cancer patients after hepatectomy.

This study aims to develop and validate a predictive nomogram for severe postoperative pleural effusion (SPOPE) in patients undergoing hepatectomy for liver cancer. A total of 536 liver cancer patients who underwent hepatectomy at the Department of Hepatobiliary Surgery I of the Affiliated Hospital of North Sichuan Medical College from January 1, 2018, to December 31, 2022, were enrolled in a retrospective observational study and comprised the training dataset. Lasso regression and logistic regression analyses were employed to construct a predictive nomogram. The nomogram was internally validated using Bootstrapping and externally validated with a dataset of 203 patients who underwent liver cancer resection at the Department of General Surgery III of the same hospital from January 1, 2020, to December 31, 2022. We evaluated the nomogram using the receiver operating characteristic curve, calibration curve, and decision curve analysis. Variables such as drinking history, postoperative serum albumin, postoperative total bilirubin, right hepatectomy, diaphragm incision, and intraoperative blood loss were observed to be associated with SPOPE. These factors were integrated into our nomogram. The C-index of the nomogram was 0.736 (95% CI: 0.692-0.781) in the training set and 0.916 (95% CI: 0.872-0.961) in the validation set. The nomogram was then evaluated using sensitivity, specificity, positive predictive value, negative predictive value, calibration curve, and decision curve analysis. The nomogram demonstrates good discriminative ability, calibration, and clinical utility.

Tuberculous pleuritis: clinical presentations and diagnostic challenges.

PURPOSE OF REVIEW: Tuberculous pleuritis (TBP) is one of the most common types of extrapulmonary tuberculosis. We highlight the latest epidemiology of TBP, the heterogeneity of its presentation and the performance of different diagnostic strategies. RECENT FINDINGS: There are differential trends in the incidences of TBP worldwide. Its incidence increased in China but decreased in the United States in the past decade. The presentation of TBP is heterogeneous regarding clinical symptoms, radiological findings and pleural fluid analysis results. Conventional microbiological tests have low sensitivities to diagnose TBP. Recent research focused on various diagnostic tools with better yield. The sensitivity of nucleic acid amplification tests (NAAT) in pleural fluid, including the latest generation of PCR and sequencing-based techniques for detecting tuberculosis, remains suboptimal. Various pleural fluid biomarkers have been explored, but there is a lack of consensus on their clinical utility and cutoff levels. SUMMARY: The heterogeneity of clinical presentation poses obstacles to diagnosing TBP. Further development of diagnostic tools, including more robust NAAT and biomarkers with additional validation, is needed before incorporation into routine clinical practice.

Evaluating the safety of intraprocedural chest tube removal during medical thoracoscopy.

BACKGROUND: Medical Thoracoscopy (MT) is a diagnostic procedure during which after accessing the pleural space the patient's negative-pressure inspiratory efforts draw atmospheric air into the pleural cavity, which creates a space to work in. At the end of the procedure this air must be evacuated via a chest tube, which is typically removed in the post-anesthesia care unit (PACU). We hypothesized that its removal intra-operatively is safe and may lead to lesser post-operative pain in comparison to its removal in the PACU. METHODS: A retrospective review was conducted of all the MT with intraprocedural chest tube removal done between 2019 to 2023 in adult patients in a single center in New York, NY by interventional pulmonology. RESULTS: A total of 100 MT cases were identified in which the chest tube was removed intra-operatively. Seventy-seven percent of cases were performed as outpatient and all these patients were discharged on the same day. Post procedure ex-vacuo pneumothorax was present in 42% of cases. Sixty-five percent of cases had some post-procedure subcutaneous emphysema, none reported any complaint of this being painful, and no intervention was needed to relieve the air. Seventy-three percent required no additional analgesia in PACU. Of the 27% that required any form of analgesia, 59% required no additional analgesia beyond the first 24 h. CONCLUSIONS: Intraprocedural CT removal for MT is safe and may decrease utilization of additional analgesia post procedure. Further prospective studies are necessary to validate these conclusions.

Diagnosis and Management of Hepatic Hydrothorax.

Hepatic hydrothorax is a pleural effusion (typically ≥500 mL) that develops in patients with cirrhosis and/or portal hypertension in the absence of other causes. In most cases, hepatic hydrothorax is seen in patients with ascites. However, ascites is not always found at diagnosis and is not clinically detected in 20% of patients with hepatic hydrothorax. Some patients have no symptoms and incidental findings on radiologic examination lead to the diagnosis of the condition. In the majority of cases, the patients present with symptoms such as dyspnea at rest, cough, nausea, and pleuritic chest pain. The diagnosis of hepatic hydrothorax is based on clinical manifestations, radiological features, and thoracocentesis to exclude other etiologies such as infection (parapneumonic effusion, tuberculosis), malignancy (lymphoma, adenocarcinoma) and chylothorax. The management strategy involves a stepwise approach of one or more of the following: Reducing ascitic fluid production, preventing fluid transfer to the pleural space, fluid drainage from the pleural cavity, pleurodesis (obliteration of the pleural cavity), and liver transplantation. The complications of hepatic hydrothorax are associated with significant morbidity and mortality. The complication that causes the highest morbidity and mortality is spontaneous bacterial empyema (also called spontaneous bacterial pleuritis).

Clinical impact of pleural fluid carcinoembryonic antigen on therapeutic strategy and efficacy in lung adenocarcinoma patients with malignant pleural effusion.

BACKGROUND/AIMS: Epidermal growth factor receptor (EGFR) mutation is important in determining the treatment strategy for advanced lung cancer patients with malignant pleural effusion (MPE). Contrary to serum carcinoembryonic antigen (S-CEA) levels, the associations between pleural fluid CEA (PF-CEA) levels and EGFR mutation status as well as between PF-CEA levels and treatment efficacy have rarely been investigated in lung adenocarcinoma patients with MPE. METHODS: This retrospective study enrolled lung adenocarcinoma patients with MPE and available PF-CEA levels and EGFR mutation results. The patients were categorized based on PF-CEA levels: < 10 ng/mL, 10-100 ng/mL, 100-500 ng/mL, and ≥ 500 ng/mL. The association between PF-CEA levels and EGFR mutation status as well as their therapeutic impact on overall survival was compared among the four groups. RESULTS: This study included 188 patients. PF-CEA level was found to be an independent predictor of EGFR mutation but not S-CEA level. The EGFR mutation rates were higher as the PF-CEA levels increased, regardless of cytology results or sample types. Among EGFR-mutant lung adenocarcinoma patients receiving EGFR-tyrosine kinase inhibitor (TKI) treatment, those with high PF-CEA levels had significantly better survival outcomes than those with low PF-CEA levels. CONCLUSION: High PF-CEA levels were associated with high EGFR mutation rate and may lead to a favorable clinical outcome of EGFR-TKI treatment in EGFR-mutant lung adenocarcinoma patients with MPE. These findings highlight the importance of actively investigating EGFR mutation detection in patients with suspected MPE and elevated PF-CEA levels despite negative cytology results.

Cell-free DNA methylation analysis as a marker of malignancy in pleural fluid.

Diagnosis of malignant pleural effusion (MPE) is made by cytological examination of pleural fluid or histological examination of pleural tissue from biopsy. Unfortunately, detection of malignancy using cytology has an overall sensitivity of 50%, and is dependent upon tumor load, volume of fluid assessed, and cytopathologist experience. The diagnostic yield of pleural fluid cytology is also compromised by low abundance of tumor cells or when morphology is obscured by inflammation or reactive mesothelial cells. A reliable molecular marker that may complement fluid cytology for the diagnosis of malignant pleural effusion is needed. The purpose of this study was to establish a molecular diagnostic approach based on pleural effusion cell-free DNA methylation analysis for the differential diagnosis of malignant pleural effusion and benign pleural effusion. This was a blind, prospective case-control biomarker study. We recruited 104 patients with pleural effusion for the study. We collected pleural fluid from patients with: MPE (n = 48), indeterminate pleural effusion in subjects with known malignancy or IPE (n = 28), and benign PE (n = 28), and performed the Sentinel-MPE liquid biopsy assay. The methylation level of Sentinel-MPE was markedly higher in the MPE samples compared to BPE control samples (p < 0.0001) and the same tendency was observed relative to IPE (p = 0.004). We also noted that the methylation signal was significantly higher in IPE relative to BPE (p < 0.001). We also assessed the diagnostic efficiency of the Sentinel-MPE test by performing receiver operating characteristic analysis (ROC). For the ROC analysis we combined the malignant and indeterminate pleural effusion groups (n = 76) and compared against the benign group (n = 28). The detection sensitivity and specificity of the Sentinel-MPE test was high (AUC = 0.912). The Sentinel-MPE appears to have better performance characteristics than cytology analysis. However, combining Sentinel-MPE with cytology analysis could be an even more effective approach for the diagnosis of MPE. The Sentinel-MPE test can discriminate between BPE and MPE. The Sentinel-MPE liquid biopsy test can detect aberrant DNA in several different tumor types. The Sentinel-MPE test can be a complementary tool to cytology in the diagnosis of MPE.

Pleural and pericardial effusions with fever and altered mental status: an atypical presentation of bartonellosis.

A male in his 60s presented to the emergency department (ED) with a 3-week history of fever and progressive confusion. Initial laboratory and radiographic workup was largely unremarkable except for moderate bilateral pleural effusions. The patient was admitted on broad-spectrum antibiotics and further workup for fever of unknown aetiology. The differential diagnosis was broadened to different zoonotic infections, and subsequent laboratory testing showed a markedly elevated Bartonella henselae IgG and Bartonella quintana IgG (1:4096 and 1:512, respectively) in addition to positive B. henselae IgM titre (>1:20). During hospitalisation, the patient became more hypoxic and was found to have enlarging pleural effusions as well as a new pericardial effusion. The patient was treated with intravenous then oral doxycycline 100 mg two times per day and oral rifampin 300 mg two times per day for 4 weeks with subsequent improvement in clinical status as well as both effusions. This case highlights a unique presentation of Bartonella and its rare manifestation of pleural and pericardial effusions.

Features which discriminate between tuberculosis and haematologic malignancy as the cause of pleural effusions with high adenosine deaminase.

BACKGROUND: Adenosine deaminase (ADA) is a useful biomarker for the diagnosis of tuberculous pleurisy (TBP). However, pleural effusions with high ADA can also be caused by other diseases, particularly hematologic malignant pleural effusion (hMPE). This study aimed to investigate the features that could differentiate TBP and hMPE in patients with pleural effusion ADA ≥ 40 IU/L. METHODS: This was a retrospective observational study of patients with pleural effusion ADA ≥ 40 IU/L, conducted at a Korean tertiary referral hospital with an intermediate tuberculosis burden between January 2010 and December 2017. Multivariable logistic regression analyses were performed to investigate the features associated with TBP and hMPE, respectively. RESULTS: Among 1134 patients with ADA ≥ 40 IU/L, 375 (33.1%) and 85 (7.5%) were diagnosed with TBP and hMPE, respectively. TBP and hMPE accounted for 59% (257/433) and 6% (27/433) in patients with ADA between 70 and 150 IU/L, respectively. However, in patients with ADA ≥ 150 IU/L, they accounted for 7% (9/123) and 19% (23/123), respectively. When ADA between 40 and 70 IU/L was the reference category, ADA between 70 and 150 IU/L was independently associated with TBP (adjusted odds ratio [aOR], 3.11; 95% confidence interval [CI], 1.95-4.95; P < 0.001). ADA ≥ 150 IU/L was negatively associated with TBP (aOR, 0.35; 95% CI, 0.14-0.90; P = 0.029) and positively associated with hMPE (aOR, 13.21; 95% CI, 5.67-30.79; P < 0.001). In addition, TBP was independently associated with lymphocytes ≥ 35% and a lactate dehydrogenase (LD)/ADA ratio < 18 in pleural effusion. hMPE was independently associated with pleural polymorphonuclear neutrophils < 50%, thrombocytopenia, and higher serum LD. A combination of lymphocytes ≥ 35%, LD/ADA < 18, and ADA < 150 IU/L demonstrated a sensitivity of 0.824 and specificity of 0.937 for predicting TBP. CONCLUSION: In patients with very high levels of pleural effusion ADA, hMPE should be considered. Several features in pleural effusion and serum may help to more effectively differentiate TBP from hMPE.

[Expert consensus on diagnosis and treatment of malignant pleural effusion caused by lung cancer].

Malignant pleural effusion (MPE) can occur in nearly all types of malignant tumors, with lung cancer being the most prevalent cause. The presence of MPE indicates an advanced stage or distant spread of the tumor, significantly reducing the patient's life expectancy. Particularly, a substantial amount of pleural effusion can impede heart and lung function, impair blood oxygen perfusion levels in the body, and greatly diminish patients' quality of life. Even when systemic treatment has alleviated the primary lung tumor in some patients, effective control over MPE remains challenging and impacts clinical outcomes. Therefore, it is crucial to implement measures for reducing or managing MPE while ensuring standardized treatment for lung cancer. In recent years, significant advancements have been made in diagnosing and treating lung cancer complicated by MPE through extensive basic and clinical research. Based on existing evidence and China's clinical practice experience, relevant experts from the China Association of Health Promotion and Education and Cancer Rehabilitation and Palliative Treatment Professional Committee of China Anti-Cancer Association (CRPC) have summarized key aspects related to diagnosis and treatment consensus opinions for lung cancer complicated by MPE. This aims to establish standardized procedures that will serve as a reference for doctors' clinical practice.

Pleural fluid carbohydrate antigen 72-4 and malignant pleural effusion: a diagnostic test accuracy study.

BACKGROUND: The prognosis of malignant pleural effusion (MPE) is poor. A timely and accurate diagnosis is the prerequisite for managing MPE patients. Carbohydrate antigen 72-4 (CA72-4) is a diagnostic tool for MPE. OBJECTIVE: We aimed to evaluate the diagnostic accuracy of pleural fluid CA72-4 for MPE. DESIGN: A prospective, preregistered, and double-blind diagnostic test accuracy study. METHODS: We prospectively enrolled participants with undiagnosed pleural effusions from two centers in China (Hohhot and Changshu). CA72-4 concentration in pleural fluid was measured by electrochemiluminescence. Its diagnostic accuracy for MPE was evaluated by a receiver operating characteristic (ROC) curve. The net benefit of CA72-4 was determined by a decision curve analysis (DCA). RESULTS: In all, 153 participants were enrolled in the Hohhot cohort, and 58 were enrolled in the Changshu cohort. In both cohorts, MPE patients had significantly higher CA72-4 levels than benign pleural effusion (BPE) patients. At a cutoff value of 8 U/mL, pleural fluid CA72-4 had a sensitivity, specificity, and area under the ROC curve (AUC) of 0.46, 1.00, and 0.79, respectively, in the Hohhot cohort. In the Changshu cohort, CA72-4 had a sensitivity, specificity, and AUC of 0.27, 0.94, and 0.86, respectively. DCA revealed the relatively high net benefit of CA72-4 determination. In patients with negative cytology, the AUC of CA72-4 was 0.67. CONCLUSION: Pleural fluid CA72-4 helps differentiate MPE and BPE in patients with undiagnosed pleural effusions.

A simple and efficient clinical prediction scoring system to identify malignant pleural effusion.

BACKGROUND: Early diagnosis of malignant pleural effusion (MPE) is of great significance. Current prediction models are not simple enough to be widely used in heavy clinical work. OBJECTIVES: We aimed to develop a simple and efficient clinical prediction scoring system to distinguish MPE from benign pleural effusion (BPE). DESIGN: This retrospective study involved patients with MPE or BPE who were admitted in West China Hospital from December 2010 to September 2016. METHODS: Patients were divided into training, testing, and validation set. Prediction model was developed from training set and modified to a scoring system. The diagnostic efficacy and clinical benefits of the scoring system were estimated in all three sets. RESULTS: Finally, 598 cases of MPE and 1094 cases of BPE were included. Serum neuron-specific enolase, serum cytokeratin 19 fragment (CYFRA21-1), pleural carcinoembryonic antigen (CEA), and ratio of pleural CEA to serum CEA were selected to establish the prediction models in training set, which were modified to the scoring system with scores of 6, 8, 10, and 9 points, respectively. Patients with scores >12 points have high MPE risk while ⩽12 points have low MPE risk. The scoring system has a high predictive value and good clinical benefits to differentiate MPE from BPE or lung-specific MPE from BPE. CONCLUSION: This study developed a simple clinical prediction scoring system and was proven to have good clinical benefits, and it may help clinicians to separate MPE from BPE.