Benefit of intrapleural fibrinolytic therapy in the treatment of complicated parapneumonic effusion and empyema.

Our study aimed to assess the benefit of intrapleural fibrinolysis before resorting to surgery to treat complicated parapneumonic effusion and empyema. We conducted a retrospective and descriptive study, including all patients hospitalized in the intensive care unit (ICU) of the Abderhaman Mami hospital, Tunisia for empyema treated with instillation of intrapleural fibrinolytic therapy between the 1st January 2000 and 31st December 2016. In all patients, empyema was diagnosed on clinical features, imaging findings (chest X-ray, thoracic echography and/or computed tomography (CT), and microbiological data. The fibrinolytic agent used was streptokinase. The efficiency of intrapleural fibrinolytic therapy was judged on clinical and paraclinical results. Among 103 cases of complicated parapneumonic effusion and empyema, 34 patients were included. The mean age was 34 years [15-81] with a male predominance (sex ratio at 2.77). Median APACH II score was 9. Fifty (50%) of the patients (n=17) had no past medical history; addictive behavior was described in 17 patients (50%). All patients were admitted for acute respiratory failure and one patient for septic shock. Pleural effusion was bilateral in 7 patients. Bacteria isolated were Streptococcus pneumonia (6 cases), Staphylococcus aureus (3 cases, including one which methicillin-resistant), Staphylococcus epidermidis (1 case), anaerobes (5 cases), and Klebsiella pneumoniae (1 case). First-line antimicrobial drug therapy was amoxicillin-clavulanate in 20 patients. A chest drain was placed in all cases in the first 38 hours of ICU admission. The median number of fibrinolysis sessions was 4 [2-9] and the median term of drainage was 7 days [3-16]. No side effects were observed. Video-assisted thoracoscopic surgery was proposed in 5 patients. The median length of hospitalization stay was 15 days [6-31]. One patient died due to multi-organ failure.

Lemierre syndrome with pulmonary empyema caused by Prevotella intermedia.

Lemierre syndrome is a rare disease that is most often caused by Fusobacterium necrophorum We present a case caused by Prevotella intermedia in a young, healthy man, complicated by multiple cavitary lung lesions, loculated pleural effusions requiring chest tube placement and trapezius abscess. Our case highlights (a) P. intermedia as a rare cause of Lemierre syndrome and (b) clinical response to appropriate antimicrobial therapy may be protracted.

Urokinase in the treatment of tuberculous pleurisy: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the efficacy of urokinase (UK) treatment for tuberculous pleural effusion (TPE). METHODS: We searched Chinese biomedical literature database, WanFang data, CNKI, PubMed, EMbase, Web of Science and The Cochrane Library for the randomized controlled trials (RCTs) of urokinase treatment for tuberculous pleurisy from January 2000 to February 2023. Pleural tuberculosis, urokinase and randomized controlled trial were used as keywords. The eligible studies were meta-analyzed by using Revman 5.4.1: risk of bias was assessed, mean difference (MD) and 95% CI were used for continuous variables, pooled studies were conducted using random-effects or fixed-effects models, forest plots were drawn to analyze efficacy, and funnel plots were drawn to discuss publication bias. RESULTS: Twenty-nine RCTs were included. The meta-analyzed results showed that, on the basis of routine anti-tuberculosis, comparison between the treatment group treated with urokinase and the control group treated with antituberculosis alone, the time of pleural effusion absorption [MD-5.82, 95%CI (- 7.77, - 3.87); P<0.00001] and the residual pleural thickness [MD-1.31, 95%CI (- 1.70, - 0.91); P<0.00001], pleural effusion drainage volume [MD 822.81, 95%CI (666.46,977.96); P<0.00001], FVC%pred [MD 7.95, 95%CI (4.51,11.40); P<0.00001], FEV1%pred [MD 12.67, 95%CI (10.09,15.24); P<0.00001] were significantly different. CONCLUSION: The clinical effect of urokinase is better than that of antituberculous therapy alone: it can increase total pleural effusion, decrease residual pleural thickness, improve the pulmonary function, and shorten the time of pleural effusion absorption.

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.

Isolated massive pleural effusion as a manifestation of chronic graft versus host disease successfully treated with corticosteroid.

Isolated pleural effusion is a rare manifestation of chronic graft versus host disease (cGVHD) after hematopoietic stem cell transplantation (HSCT). We herein report a 58-year-old woman presenting with massive pleural effusion approximately 1 year after allogeneic HSCT, who was successfully treated with corticosteroid. She had discontinued tacrolimus approximately 1 month before she presented with pleural effusion, which was attributed to cGVHD after a thorough exclusion process. This case illustrates a unique manifestation of atypical cGVHD and highlights the need for prompt therapy initiation.

Effect of early administration of tolvaptan on pleural effusion post-hepatectomy.

PURPOSE: This study evaluated the efficacy of tolvaptan administration at the early stage after hepatectomy to control pleural effusion and improve the postoperative course. METHODS: Patients were administered tolvaptan (7.5 mg) and spironolactone (25 mg) from postoperative day 1 to postoperative day 5 (tolvaptan group, n = 68) for 13 months. Early administration of tolvaptan was not provided in the control group (n = 68); however, diuretics were appropriately administered according to the patient's condition. The amount of pleural effusion on computed tomography on postoperative day 5 was compared between the two groups. RESULTS: The amount of pleural effusion and increase in body weight on postoperative day 5 showed significant differences in both groups (p < 0.001 and p = 0.019, respectively). However, the rate of pleural aspiration and the duration of postoperative hospitalization were comparable between the groups. The amount of intraoperative blood loss and lack of early administration of tolvaptan were identified as independent risk factors contributing to pleural effusion on multivariate analysis. CONCLUSION: Early administration of tolvaptan to patients after hepatectomy was found to be capable of controlling postoperative pleural effusion and increase in body weight, but it did not reduce the rate of pleural aspiration or the hospitalization period.

Chylothorax after chimeric antigen receptor T cell therapy for relapsed and refractory diffuse large B-cell lymphoma: A case report.

RATIONALE: Anti-CD19-targeted chimeric antigen receptor (CAR) T cell therapy is effective in treating relapsed/refractory diffuse large B-cell lymphoma (DLBCL). This therapy is associated with several side effects that can be life-threatening such as cytokine release syndrome (CRS). However, chylothorax associated with CRS after CAR-T therapy has not been reported. PATIENT CONCERNS: A 23-year-old male diagnosed with DLBCL relapsing after autologous peripheral blood stem cell transplantation was treated with anti-CD19-targeted CAR-T cell therapy. After CAR-T cell transfusion, he developed grade 3 CRS includes fever, dyspnea, tachycardia and hypotension. The symptoms of CRS persisted and chest plain film revealed bilateral pleural effusion. DIAGNOSIS: Chylothorax was confirmed by the pleural effusion analysis that triglyceride level was 1061 mg/dL. Bacterial and fungal culture of pleural fluid reported no pathogen was detected. Cytological examination of pleural effusion revealed no malignant cells. INTERVENTIONS: The chylothorax resolved after treatment with intravenous administration of tocilizumab. OUTCOMES: On 30-day follow-up, the patient was in stable clinical condition with complete remission of DLBCL on whole-body positron emission tomography scan. LESSONS: We reported a rare case of CAR-T associated chylothorax in a patient with relapsed and refractory DLBCL. Grade 3 CRS with high interleukin-6 level was presented in our patient. The symptoms of CRS were improved with tocilizumab treatment and the chylothorax resolved later on. It is suggested that high interleukin-6 releases might induce chyle leakage resulting from activations of endothelium and coagulation. Our finding highlights the occurrence of chylothorax during the course of CAR-T cell therapy and the importance of proper monitoring and prompt management of this life-threatening side effect.

Pleural penetration of amoxicillin and metronidazole during pleural infection: An ambispective cohort study.

OBJECTIVES: The pharmacokinetics of antibiotics in pleural fluid during pleural infections has been poorly described. This study aimed to explore amoxicillin and metronidazole diffusion into the pleural space. METHODS: This was an ambispective, single-centre study that included patients with complicated parapneumonic effusion or pleural empyema managed with repeated therapeutic thoracentesis as first-line treatment between 2014 and 2022. Pleural steady-state or trough concentrations of amoxicillin and metronidazole were measured, with a lower limit of quantification of 5 mg/L. RESULTS: Seventy paired blood and pleural samples were analysed from 40 patients. The median (interquartile range) patient age was 55 years (45-67 years) and 88% were male. The median patient weight was 65.8 kg (57.3-82 kg) and median plasma albumin concentration was 29.7 g/L (23.7-33.9 g/L). Median creatinine clearance was 106 mL/min (95-117 mL/min). Median amoxicillin pleural concentrations in patients treated with oral, bolus and continuous intravenous administrations (6 g/day) were, respectively, 5.2 (<5-6.4), 9.4 (8-13.1) and 10.8 (7.1-13.1) mg/L. Pleural concentrations were <5 mg/L in 5/11 samples (45%) with oral treatment and 6/59 (10%) with intravenous treatment. Median metronidazole pleural concentrations were 18.4 (15.7-22.8) mg/L, with all patients being treated orally (1.5 g/day). CONCLUSIONS: Oral metronidazole (1.5 g/day) and intravenous amoxicillin (6 g/day) achieved therapeutic targets in pleural fluid in most cases, but oral amoxicillin did not.

Combined intrapleural alteplase and DNase therapy in complicated pleural infection arising from postsurgery oesophageal leak.

Managing a complicated pleural infection related to postsurgery can pose a clinical challenge, especially when initial interventions such as intercostal chest drain and antibiotics prove ineffective. We describe a man in his mid-60s who developed a recurrence of exudative pleural effusion caused by an oesophageal leak following laparoscopic total gastrectomy with Roux-y oesophagojejunostomy for gastric adenocarcinoma. Surgical repairs and oesophageal stenting were performed to address the oesophageal leak. Despite attempts at intercostal chest tube drainage, ultrasonography-guided targeted drainage of the locule and antibiotics, he did not show any improvement. He was unfit for surgical decortication. Due to the risk of bleeding, we chose a modified dose of intrapleural alteplase 5 mg and DNase 5 mg at 12-hour intervals for a total of three doses. This led to the complete resolution of the effusion. This case highlights that intrapleural tPA/DNase can be an adjunctive therapy in postsurgery-related complicated pleural effusion.

Recurrent pleural effusion as a rare manifestation after prolonged PD1 inhibitor (camrelizumab)-based immunotherapy: A case report.

Immune-related adverse events (irAEs) pose a significant challenge for the widespread adoption of immuno-oncology therapies, but their symptoms can vary widely. In particular, the relationship between irAEs and pleural effusion (PE) in patients with advanced non-small cell lung cancer (NSCLC) remains unclear. In this report, we present the case of an advanced NSCLC patient who developed persistent PE despite receiving camrelizumab (an anti-programmed death receptor 1 [PD-1] antibody) and chemotherapy as first-line treatment. While the patient's tumor biomarkers decreased after multiple cycles of treatment, the PE persisted despite negative findings on cytology and pleural biopsy. Additionally, the use of anti-angiogenic drugs failed to alleviate the PE. Screening for rheumatic connective tissue markers and tuberculosis yielded negative results, but intrathoracic dexamethasone injections in two doses resulted in a significant reduction of the PE. This case suggests that PE may represent a rare type of irAE that should be monitored for during prolonged immuno-oncology therapy.

Association between intrapleural urokinase monotherapy and treatment failure in patients with pleural infection: a retrospective cohort study.

BACKGROUND: Pleural infection, an infection of the pleural space, is frequently treated with antibiotics and thoracic tube drainage. In case of insufficient drainage, an intrapleural fibrinolytic agent is considered before surgical intervention. However, the effectiveness of fibrinolytic monotherapy is still controversial. Therefore, we aimed to examine the association between urokinase monotherapy and treatment failure in patients with pleural infection. METHODS: In this retrospective observational study, patients with pleural infection underwent chest tube insertion were divided into two groups including patients treated with or without intrapleural instillation of urokinase. The propensity score overlap weighting was used to balance the baseline characteristics between the groups. Treatment failure was defined by the composite primary outcome of in-hospital death and referral for surgery. RESULTS: Among the 94 patients, 67 and 27 patients were in the urokinase and non-urokinase groups, respectively. Urokinase monotherapy improved the composite outcome between the groups (19.4% vs. 48.1%, p = 0.01). After adjusting using propensity score overlap weighting, urokinase monotherapy improved the composite outcome compared to the non-urokinase group (19.0% vs. 59.5%, p = 0.003). CONCLUSIONS: Urokinase monotherapy can be an important nonsurgical treatment option for patients with pleural infection. TRIAL REGISTRATION: The participants were retrospectively registered.

Choice of intrapleural fibrinolytic agents in the treatment of adult complicated parapneumonic effusion and empyema: Network meta-analysis.

BACKGROUND: The appropriate use of intrapleural fibrinolytic agents in patients with complicated parapneumonic effusion and empyema remains unclear, especially regarding the choice of fibrinolytic agents. We conducted a network meta-analysis comparing outcomes of intrapleural fibrinolytic agents in patients with complicated parapneumonic effusion and empyema. METHODS: MEDLINE and EMBASE were searched through April 2022 to identify randomized controlled trials (RCTs) that investigated outcomes in patients with complicated parapneumonic effusion or empyema who were treated with intrapleural fibrinolytic agents. The outcomes of interest were surgical requirements, bleeding, length of hospital stay, and all-cause mortality. RESULTS: Our analysis included 10 RCTs that enrolled 1085 patients treated with intrapleural tissue plasminogen activator (TPA) (n = 138), TPA + deoxyribonuclease (DNase) (n = 52), streptokinase (n = 311), urokinase (n = 75), DNase (n = 51), or placebo (n = 458). The rates of surgical requirement were significantly lower with TPA and TPA + DNase than with placebo (risk ratio [RR]; 95% confidence interval [CI] = 0.36 [0.14-0.97], p = 0.038, RR [95% CI] = 0.25 [0.08-0.78], p = 0.017, respectively). The risk of bleeding was higher with TPA + DNase than with placebo (RR [95% CI] = 10.91 [1.53-77.99], p = 0.017), as well as TPA and TPA + DNase than with urokinase (RR [95% CI] = 17.90 [1.07-299.44], p = 0.044, RR [95% CI] = 89.3 [2.88-2772.49], p = 0.010, respectively). All-cause mortality was similar among the groups. CONCLUSION: TPA and TPA + DNase reduced the rates of surgical requirement compared with placebo. However, TPA + DNase increased the risk of bleeding compared with placebo. Intrapleural agents for complicated parapneumonic effusion and empyema should be selected with an individual risk assessment.

Drug transdermal delivery by electrophonophoresis can increase the concentration of rifampicin in the pleural effusion of patients with tuberculous pleurisy but has no effect on the concentration of rifampicin in plasma.

BACKGROUND: Electrophonophoresis (EP) has been widely used in various clinical fields. The purpose of this study was to evaluate the dermal permeability of rifampicin (RIF) in patients with tuberculous pleurisy assisted by EP and to verify the clinical application of this percutaneous drug delivery system in the treatment of tuberculous pleurisy, verify the system's influencing factors, and determine whether plasma drug concentration was increased. METHOD: Patients were given oral isoniazid 0.3-0.4 g, rifampicin 0.45-0.60 g, pyrazinamide 1.0-1.5 g and ethambutol 0.75 g according to their body weight once a day. After 5 days of anti-tuberculosis treatment, 3 ml of rifampicin was delivered transdermally with EP. Pleural effusion and peripheral blood samples in patients were collected at and after dosing. The drug concentration in the samples was determined by high-performance liquid chromatography. RESULT: The median plasma concentration (interquartile ranges) of RIF in 32 patients was 8.80 (6.65, 13.14) µg/ml before RIF transdermal injection plus EP and decreased to 8.09 (5.58, 11.82) µg/ml after 30 min of RIF transdermal injection plus EP. The RIF concentration in pleural effusion was higher than that before RIF-transdermal plus EP. In patients who received RIF via EP transdermal administration, the concentration of the drug at the local site was statistically higher than the concentration at the local site prior to penetration. However, no such enhancement was observed in plasma after transdermal administration of RIF. CONCLUSION: EP can effectively increase the concentration of rifampicin in the pleural effusion of tuberculous pleurisy and has no effect on the circulating plasma concentration. The increased concentration of the drug in the lesion helps to destroy the bacteria.

Management and Risk Factors for Pleural Effusion in Japanese Patients with Chronic Myeloid Leukemia Treated with First-line Dasatinib in Real-world Clinical Practice.

Objective Pleural effusion (PE) is a common adverse event that occurs during dasatinib therapy for chronic myeloid leukemia (CML). However, the pathomechanism of PE and appropriate management of Asian patients with CML have not been elucidated. This study investigated the incidence rate, risk, and appropriate management of PE in Asian patients with CML treated with dasatinib. Methods We retrospectively collected data on patients in the chronic phase of CML who received first-line dasatinib therapy and were registered in the CML-Cooperative Study Group database. Patients We identified 44 cases of PE in a series of 89 patients and analyzed previously reported risk factors and effective management of PE. Results A univariate analysis revealed that age, diabetes mellitus, chronic renal failure, hypertension, the history of cardiovascular events, and dasatinib dose were significantly associated with PE. A multivariate analysis revealed that age ≥65 years old was the only independent risk factor for PE. Dasatinib dose reduction and switching to a tyrosine kinase inhibitor showed a statistically significant difference in effectively reducing PE volume compared to single diuretic use. Conclusion Although further studies are warranted, our observations showed that advanced age is a significant risk factor for PE, and tyrosine kinase inhibitor dose reduction or replacement of dasatinib may be an effective management strategy for PE in Asian CML patients who received first-line treatment with dasatinib in real-world clinical practice.

Intrapleural tissue plasminogen activator and deoxyribonuclease administered concurrently and once daily for complex parapneumonic pleural effusion and empyema.

BACKGROUND: Pleural infection is life-threatening and increasingly prevalent. In addition to usual care, twice-daily, separate administration of tissue plasminogen activator and deoxyribonuclease (tPA-DNase) reduces radiological pleural opacity with lower surgical referral rates. AIMS: This retrospective cohort study examines the use of once-daily, concurrent administration of tPA-DNase for complex parapneumonic pleural effusion and empyema. METHODS: Patients with pleural infection who received intrapleural tPA-DNase between October 2014 and July 2020 at Logan Hospital, where it is given concurrently and once-daily as salvage therapy, were retrospectively identified. Radiographic opacification, inflammatory markers, clinical response and complications were examined. RESULTS: Thirty-one patients were identified. Mean age was 48.8 years (standard deviation [SD], 17.2). Median tPA-DNase administration was 3 (interquartile range [IQR], 2-3). Chest x-ray pleural opacity decreased significantly (P = 0.047) from a median of 39.6% (IQR, 28.8-65.7%) to 9.7% (IQR, 2.5-23.2%), a median relative reduction of 75.5% (IQR, 47.7-93.9%). White cell count and C-reactive protein improved significantly (P = 0.002 and P = 0.032, respectively) from a median of 16.3 × 109 /L (IQR, 11.8-20.6 × 109 /L) to 9.9 × 109 /L (IQR, 8.0-12.3 × 109 /L) and 311.0 mg/L (IQR, 218.8-374.0 mg/L) to 69.0 mg/L (IQR, 36.0-118.0 mg/L), respectively. No patients experienced significant bleeding or died. Five patients (16.1%) were referred for surgery. CONCLUSION: This is pilot evidence that a practical regimen of concurrent, once-daily intrapleural tPA-DNase improved pleural opacification and inflammatory markers without bleeding or mortality. The surgical referral rate was higher than in studies assessing twice-daily administration, though the validity of this outcome as a measure of treatment success is limited, and further studies are needed to assess the optimal dose and frequency of intrapleural therapy and indications for surgical referral.

Clinical relevance of bronchiectasis in patients with community-acquired pneumonia.

BACKGROUND: Data regarding the clinical characteristics and treatment outcomes of patients with community-acquired pneumonia (CAP) and bronchiectasis (BE) are rare. This study aims to elucidate the clinical relevance of BE in patients with CAP. METHODS: Patients hospitalized with CAP in a single center were retrospectively analyzed and divided into significant BE (BE with ≥ 3 lobes or cystic BE on computed tomography) and control groups. Clinical and microbiological characteristics were compared between the two groups. RESULTS: In the final analysis, 2112 patients were included, and 104 (4.9%) had significant BE. The significant BE group exhibited a higher prevalence of sputum production, dyspnea, and complicated parapneumonic effusion or empyema than the control group. Pseudomonas aeruginosa was more frequently isolated in the significant BE group than in the control group, whereas Mycoplasma pneumoniae was less commonly identified. Length of hospital stay (LOS) was significantly longer in the significant BE group than the control group (12 [8-17] days vs. 9 [6-13] days, p < 0.001). In contrast, 30-day and in-hospital mortality rates did not significantly differ between the two groups. Furthermore, significant BE was an independent predictor of prolonged hospitalization in two models based on CURB-65 and pneumonia severity index. CONCLUSIONS: Significant BE occurred in approximately 5% of patients with CAP and was more likely to be associated with sputum, dyspnea, complicated parapneumonic effusion or empyema, and isolation of P. aeruginosa. Significant BE was an independent predictor of LOS in patients with CAP.

The clinical significance of and the factors associated with macrolide resistance and poor macrolide response in pediatric Mycoplasma pneumoniae infection: A retrospective study.

BACKGROUND: Macrolide-resistant Mycoplasma pneumoniae (MRMP) infection is increasing worldwide. However, its clinical significance is still uncertain. METHODS: The data of the Laboratory Medicine Department of Chang Gung Memorial Hospital in northern Taiwan was searched for children with molecular confirmed macrolide-susceptible Mycoplasma pneumoniae (MSMP) and MRMP infections between January 2011 and December 2018. The clinical features, laboratory data, and chest image presentations were compared between patients with MRMP and MSMP infections and between patients with good and poor macrolide response, respectively. RESULTS: Records from 158 patients were recovered. Of the enrolled patients 34 (22%) suffered MRMP infection, 27 (17%) had pleural effusions, and 47 (32%) had poor macrolide response. The macrolide resistance rate was 12% in 2011, 20% between 2015 and 2016, and 50% between 2017 and 2018, respectively. Other than a poor macrolide response, the MRMP and MSMP infections are clinically indistinguishable. The presence of pleural effusion and MRMP infections were found to be independently associated with a poor macrolide response, with odds ratios (95% confidence interval) of 14.3 (4.9-42.0) and 14.6 (5.4-40), respectively. The macrolide resistance rate of the patients with a poor macrolide response was 49% and 18% among all the patients enrolled and the patients with a pleural effusion, respectively. CONCLUSION: The macrolide resistance rate had possibly increased in recent years in Taiwan and should be continuously monitored. In addition, the macrolide response could be misleading in predicting a macrolide resistance especially for the patients with a pleural effusion.

Conservative Treatment of Parapneumonic Effusion in Children: Experience From a 10-Year Consecutive Case Series.

BACKGROUND: In children with parapneumonic effusion (PPE), it remains unclear when conservative treatment with antibiotics suffixes or when pleural drainage is needed. In this study we evaluate clinical features and outcomes of children with PPE. METHODS: A retrospective, multicentre cohort study at 4 Dutch pediatric departments was performed, including patients 1-18 years treated for PPE between January 2010 and June 2020. RESULTS: One hundred thirty-six patients were included (mean age 8.3 years, SD 4.8). 117 patients (86%) were treated conservatively and 19 (14%) underwent pleural drainage. Patients undergoing pleural drainage had mediastinal shift more frequently compared with conservatively treated patients (58 vs. 3%, difference 55%; 95% CI: 32%-77%). The same accounted for pleural septations/pockets (58 vs. 11%, difference 47%; 95% CI: 24%-70%), pleural thickening (47 vs. 4%, difference 43%; 95% CI: 20%-66%) and effusion size (median 5.9 vs. 2.7 cm; P = 0.032). Conservative management was successful in 27% of patients (4 of 15) with mediastinal shift, 54% of patients (13 of 24) with septations/pockets, 36% of patients (5 of 14) with pleural thickening, and 9% of patients (3 of 32) with effusions >3 cm, all radiological signs generally warranting pleural drainage. In patients treated conservatively, median duration of hospitalization was 5 days (IQR 4-112) compared with 19 days (IQR 15-24) in the drainage group ( P < 0.001), without significant difference in readmission rate (11 vs. 4%, difference 6%; 95% CI: -8%-21%). CONCLUSION: This study suggests that the greater amount of children with PPE could be treated conservatively with antibiotics only, especially in absence of mediastinal shift, pleural septations/pockets, pleural thickening or extensive effusions.