From Bedside to the Bench—A Call for Novel Approaches to Prognostic Evaluation and Treatment of Empyema

Empyema, a severe complication of pneumonia, trauma, and surgery is characterized by fibrinopurulent effusions and loculations that can result in lung restriction and resistance to drainage. For decades, efforts have been focused on finding a universal treatment that could be applied to all patients with practice recommendations varying between intrapleural fibrinolytic therapy (IPFT) and surgical drainage. However, despite medical advances, the incidence of empyema has increased, suggesting a gap in our understanding of the pathophysiology of this disease and insufficient crosstalk between clinical practice and preclinical research, which slows the development of innovative, personalized therapies. The recent trend towards less invasive treatments in advanced stage empyema opens new opportunities for pharmacological interventions. Its remarkable efficacy in pediatric empyema makes IPFT the first line treatment. Unfortunately, treatment approaches used in pediatrics cannot be extrapolated to empyema in adults, where there is a high level of failure in IPFT when treating advanced stage disease. The risk of bleeding complications and lack of effective low dose IPFT for patients with contraindications to surgery (up to 30%) promote a debate regarding the choice of fibrinolysin, its dosage and schedule. These challenges, which together with a lack of point of care diagnostics to personalize treatment of empyema, contribute to high (up to 20%) mortality in empyema in adults and should be addressed preclinically using validated animal models. Modern preclinical studies are delivering innovative solutions for evaluation and treatment of empyema in clinical practice: low dose, targeted treatments, novel biomarkers to predict IPFT success or failure, novel delivery methods such as encapsulating fibrinolysin in echogenic liposomal carriers to increase the half-life of plasminogen activator. Translational research focused on understanding the pathophysiological mechanisms that control 1) the transition from acute to advanced-stage, chronic empyema, and 2) differences in outcomes of IPFT between pediatric and adult patients, will identify new molecular targets in empyema. We believe that seamless bidirectional communication between those working at the bedside and the bench would result in novel personalized approaches to improve pharmacological treatment outcomes, thus widening the window for use of IPFT in adult patients with advanced stage empyema.

Effectiveness of Intrapleural Tissue Plasminogen Activator and Dornase Alfa vs Tissue Plasminogen Activator Alone in Children with Pleural Empyema: A Randomized Clinical Trial

IMPORTANCE

Clinical guidelines recommend that children with pleural empyema be treated with chest tube insertion and intrapleural fibrinolytics. The addition of dornase alfa (DNase) has been reported to improve outcomes in adults but remains unproven in children.

OBJECTIVE

To determine if intrapleural tissue plasminogen activator (tPA) and DNase is more effective than tPA and placebo at reducing hospital length of stay in children with pleural empyema.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, parallel-group, placebo-controlled, superiority randomized clinical trial included children diagnosed as having pleural empyema requiring drainage aged 6 months to 18 years treated at 6 tertiary Canadian children's hospitals. A total of 379 children were assessed for eligibility; 281 were excluded and 98 were randomized. One child was excluded after randomization for not meeting the inclusion criteria. Data were collected from March 4, 2013, to December 13, 2017.

INTERVENTIONS

Participants underwent chest tube insertion and 3 daily administrations of intrapleural tPA, 4 mg, followed by DNase, 5 mg (intervention group), or 5 mL of normal saline (placebo; control group). Participants, families, clinical staff, and members of the study team were blinded to allocation.

MAIN OUTCOMES AND MEASURES

The primary outcome was hospital length of stay from chest tube insertion to discharge. Secondary outcomes included time to meeting discharge criteria, time to chest tube removal, mean fever duration, additional pleural drainage procedures, hospital readmissions, and total health care cost.

RESULTS

Of the 97 analyzed children with pleural empyema, 52 (54%) were male, and the mean (SD) age was 5.1 (3.6) years. A total of 49 children were randomized to tPA and DNase and 48 were randomized to tPA and placebo. Treatment with tPA and DNase was not associated with decreased hospital length of stay compared with tPA and placebo (mean [SD] length of stay, 9.0 [4.9] vs 9.1 [5.3] days; mean difference, -0.1 days; 95% CI, -2.0 to 2.1; P = .96). Similarly, no significant differences were observed for any of the secondary outcomes. Of the 14 adverse events in the tPA and DNase group, 6 (43%) were serious; of the 21 adverse events in the tPA and placebo group, 8 (38%) were serious. There were no deaths.

CONCLUSIONS AND RELEVANCE

The addition of DNase to intrapleural tPA for children with pleural empyema had no effect on hospital length of stay or other outcomes compared with tPA with placebo. Clinical practice guidelines should continue to support the use of chest tube insertion and intrapleural fibrinolytics alone as first-line treatment for pediatric empyema.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01717742.

Severe Pulmonary Infection in a 20-Month-Old Female

Community-Acquired Pneumonia (CAP) is a common reason for hospitalization of a pediatric patient. We report a 20-month-old female admitted for suspected CAP. History included a week-long cough, fever, dyspnea, single occurrence of seizure-like activity, and a sick contact. Initial chest X-ray (CXR) showed left lower lobe pneumonia and parapneumonic effusion with a complex left pleural effusion. Ultrasound findings prompted the need for contrast-enhanced computed tomography (CT) of the chest. Contrast-enhanced CT of the chest confirmed a large pleural effusion with major atelectasis and mediastinal shift. The patient was treated with empiric antibiotics, video-assisted thoracoscopic surgical (VATS) decortication of empyema, and chest tube placement. Due to intraoperative complications, the VATS decortication was aborted and patient was transferred to the pediatric intensive care unit (PICU). A thoracentesis with culture failed to isolate a bacterial organism. Dexamethasone was started after repeat CXR showed persistent infiltrate. Subsequent contrast-enhanced CT of the chest showed a large collection of air and persistent consolidation. The patient received repeat VATS decortication and reinsertion of a chest tube. Repeat pleural fluid cultures failed to isolate a bacterial organism. Infectious disease (ID) consult recommended linezolid 140 mg Q8H for 4 weeks. Seven days after second VATS, a respiratory pathogen panel was positive for rhinovirus/enterovirus. With resolution of leukocytosis and clinical improvement, the patient was discharged with the chest tube in place and pediatric surgery outpatient follow-up. After three months, sequalae from both the infection and interventions presented .

Intrapleural Dornase and Tissue Plasminogen Activator in pediatric empyema (DTPA): a study protocol for a randomized controlled trial

BACKGROUND

A randomized controlled trial of adults with empyema recently demonstrated decreased length of stay in hospital in patients treated with intrapleurally administered dornase alfa and fibrinolytics compared to fibrinolytics alone. Whether this treatment strategy is safe and effective in children remains unknown.

METHODS/DESIGN

This study protocol is for a superiority, placebo-controlled, parallel-design, multicenter randomized controlled trial. The participants are previously well children admitted to a children's hospital with a diagnosis of empyema requiring chest tube insertion and fibrinolytics administered intrapleurally. Children will be randomized after the treating physician has decided that pleural drainage is required but prior to chest tube insertion. After chest tube insertion, participants in the treatment group will receive intrapleurally administered tissue plasminogen activator (tPA) 4 mg followed by dornase alfa 5 mg. Participants in the placebo group will receive tPA 4 mg followed by normal saline. Study treatments will be administered once daily for 3 days. All participants, parents or caregivers, clinicians, and research personnel will remain blinded. The primary outcome is length of stay from chest tube insertion to discharge from hospital. Secondary outcomes include time to meeting discharge criteria, chest tube duration, fever duration, need for additional procedures, adverse events, hospital readmission, cost of hospitalization, and mortality.

DISCUSSION

This multicenter randomized controlled trial will assess the safety, effectiveness, and cost-effectiveness of combined treatment with dornase alfa and fibrinolytics compared to fibrinolytics alone for the treatment of empyema in children.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01717742 . Registered on 8 October 2012.

Community-associated Staphylococcus aureus pneumonia among Greek children: epidemiology, molecular characteristics, treatment, and outcome

Staphylococcus aureus is an infrequent cause of community-associated (CA-SA) pneumonia in children. The aim of this study was to evaluate the clinical, epidemiological, microbiological, and molecular characteristics of CA-SA pneumonia among children hospitalized in two large tertiary care referral centers during an 8-year period. Cases of CA-SA pneumonia admitted between 2007 and 2014 were retrospectively examined through medical record review. Molecular investigation was performed for available strains; mecA, Panton-Valentine leukocidin (PVL) (lukS-lukF-PV), and fibronectin binding protein A (fnbA) genes were detected by polymerase chain reaction (PCR). Clones were assigned by agr groups, pulsed-field gel electrophoresis (PFGE), SCCmec, and multilocus sequencing typing (MLST). In total, 41 cases were recorded (boys, 61 %), with a median age of 4.3 months (range, 1-175). Methicillin-resistant S. aureus (MRSA) accounted for 31 cases (75.6 %). Complications included empyema (25/41, 61 %), pneumatoceles (7/41, 17 %), and lung abscess (1/41, 2.5 %). Intensive care unit (ICU) admission was required in 58.5 %. Two deaths occurred (4.9 %). Definitive therapy was based on vancomycin with or without other antibiotics (55.9 %), followed by clindamycin and linezolid (26.5 % each). All isolates were susceptible to vancomycin (MIC90 2 mg/L, range 1-2), teicoplanin, and linezolid, whereas 26.8 % were resistant to clindamycin. Among the 25 studied strains, 20 were mecA-positive (MRSA), carrying also the fnbA gene. Of these, 90 % belonged to the ST80-IV/agr3/PVL-positive clone. Methicillin-susceptible S. aureus (MSSA) strains showed polyclonality, 3/5 were PVL-positive, and 3/5 were fnbA-positive. MRSA and particularly the ST80-IV clone predominated among staphylococcal pneumonia cases in children. Treatment provided was effective in all but two patients, despite the relatively high minimum inhibitory concentration (MIC) of vancomycin and a high resistance to clindamycin.

Trends and practice patterns in the management of thoracic empyema

Background

This study explored the modern treatment of thoracic empyema. We evaluated outcomes of various operative approaches in both academic and nonacademic institutions.

Methods

We queried the Society of Thoracic Surgeons National Database for patients undergoing thoracic procedures with a primary diagnosis of empyema between 2009 and 2011. We compared treatment outcomes of patients having procedures at academic ( n = 1101, 28.3%) and nonacademic ( n = 2790, 71.7%) medical centers.

Results

Empyema treatments recorded in the database included tube thoracostomy ( n = 325, 8.4%), video-assisted thoracic surgery ( n = 1992, 51.2%), and thoracotomy ( n = 1574, 40.5%). Academic centers had higher rates of treatment by thoracostomy (13.8% vs. 6.2%), similar treatment rates of video-assisted thoracic surgery (49.9% vs. 51.7%), and lower rates of thoracotomy (36.3% vs. 42.1%) compared to nonacademic centers ( p < 0.001). Academic centers treated almost twice as many complicated empyemas with fistulas (11.4% vs. 6.5%, p < 0.001). Postoperative length of stay was higher in the academic centers (interquartile range 5–13 vs. 4–11 days, p = 0.001), while mechanical ventilation >48 h was more frequent in the nonacademic centers (7.6% vs. 4.4%, p = 0.013).

Conclusion

Surgeons in both academic and nonacademic centers use selective surgical approaches for treatment of thoracic empyema, depending on the clinical condition of the patient, with fairly equivalent results across all procedure types.

The role of thoracoscopic debridement in the treatment of parapneumonic empyema

AIM

To evaluate the efficacy of early video-assisted thoracoscopic debridement in patients with the fibropurulent phase of parapneumonic empyema.

PATIENTS AND METHODS

40 patients with parapneumonic empyema resistant to 2 weeks of antibiotic therapy, were randomly divided into 2 groups. In group 1 (20 patients), antibiotic therapy and irrigation was continued, and in group 2 (20 patients), video-assisted thoracoscopic debridement was performed. The 2 groups were compared in terms of therapeutic results.

RESULTS

The male/female ratio was 29/11. Group 1 included 16 men and 4 women with a mean age of 54 years, and mean hospital stay was 41 days. Group 2 consisted of 14 men and 6 women with a mean age of 51 years, and mean hospital stay was 23 days. Considering the therapeutic results, 12 patients in group 1 were cured by antibiotic therapy and irrigation, whereas 8 required decortication and pleurectomy with thoracotomy. In group 2, 18 patients were cured by video-assisted thoracoscopic debridement, and 2 underwent thoracotomy and decortication due to intraoperative bleeding. A significant difference in therapeutic results was noted between the groups (p = 0.028).

CONCLUSION

Video-assisted thoracoscopic debridement provides a high success rate and less invasive treatment for the early stages of empyema.