Intrapleural fibrinolytic therapy for pleural infection

Intrapleural Urokinase Injection after Medical Thoracoscopy for Empyema and Complicated Para-Pneumonic Effusion: A Case Series

Empyema and complicated para-pneumonic effusion (CPPE) often require surgical intervention because of insufficient antibiotic effect and chest tube drainage. From January 2017 to September 2021, we encountered seven patients who underwent intrapleural urokinase injection after medical thoracoscopy for the treatment of empyema or CPPE. None of the seven patients required further surgical interventions or showed any complications associated with the therapeutic procedures. The combined use of intrapleural urokinase injections and medical thoracoscopy may be an effective and safe therapeutic option for the management of empyema and CPPE.

Intrapleural use of urokinase and DNase in pleural infections managed with repeated thoracentesis: A comparative cohort study

Introduction

Evacuation of infected fluid in pleural infections is essential. To date, the use of an intrapleural fibrinolytic agent such as urokinase and DNase has not yet been assessed in infections managed by repeated therapeutic thoracentesis (RTT).

Methods

We performed a retrospective comparative study of two successive cohorts of consecutive patients with pleural infections from 2001 to 2018. Between 2001 and 2010, patients had RTT with intrapleural urokinase (RTT-U). After 2011, patients received intrapleural urokinase and DNase with RTT (RTT-UD). Data were collected through a standardized questionnaire.

Results

One hundred and thirty-three patients were included: 93 were men and the mean age was 59 years (standard deviation 17.2). Eighty-one patients were treated with a combination of intrapleural urokinase and DNase, and 52 were treated with intrapleural urokinase only. In the RTT-UD, RTT failure occurred in 14 patients (17%) compared to 10 (19%) in the RTT-U group (P = 0.82). There was no difference between the two groups in intensive care unit admission, surgical referrals or in-hospital mortality. RTT-UD was associated with faster time to apyrexia (aOR = 0.51, 95%CI [0.37–0.72]), a reduced length of hospital stay (aOR = 0.61, 95%CI [0.52–0.73]) and a higher volume of total pleural fluid retrieved (aOR = 1.38, 95%CI [1.02–1.88]). Complications were rare with only one hemothorax in the RTT-UD group and no pneumothorax requiring drainage in either group.

Conclusion

Compared to urokinase only, intrapleural use of urokinase and DNase in RTT was associated with quicker defervescence, shorter hospital stay and increased volumes of pleural fluid drained. Randomized controlled trials evaluating urokinase and DNase with RTT technique would be required to confirm these results.

Intraabdominal urokinase in the treatment of loculated infected ascites in cirrhosis

Cirrhotic patients may present loculated ascites. We report a case of a 49-years old patient with cirrhosis and loculated infected ascites. Conventional and ultrasound (US)-guided paracentesis were ineffective. Moreover, US-guided drainages with 10 F drains could drain only small quantities of ascites localized in the largest loculated areas. Despite an adapted and long antibiotic therapy, the infection persisted. Intraabdominal fibrinolysis allowed the destruction of the fibrin septa, a better drainage and the sterilization of the ascites fluid. This is the first case report of effective intraabdominal fibrinolysis with urokinase in difficult to treat loculated infected ascites.

Alteplase and DNase for the treatment of pleural empyema in rats

BACKGROUND AND OBJECTIVES

Adjunctive intrapleural fibrinolytic is an option to treat empyema at fibrinopurulent stage, but there is controversy about which should be use. Our objective is to evaluate the action of alteplase and/or desoxyribonuclease at physical and chemical properties in vitro pus derived from an experimental induced empyema in rats.

METHODS

Streptococcus pneumoniae was introduced into the pleural cavity by thoracentesis through pleural pressure monitor. Animals were euthanized after 24 h, with macroscopic thoracic evaluation and measurement of amount of intrapleural liquid that was posteriorly stored at -80 °C. Selected samples were randomly distributed into four groups, then thawed at room temperature before exposure to one of the following: G1 = alteplase (n = 12), G2 = DNase (n = 12), G3 = alteplase + DNase (n = 12), or G4 = saline (n = 6). The mean molecular size in the fluid portion of the empyema was evaluated using dynamic light scattering; viscosity of the empyema fluid was measured using the drip method.

RESULTS

Macroscopic showed purulent liquid, with fibrin and septation, with mean volume of 4.16 ml (0.5-8 ml). All samples were culture-positive for Streptococcus pneumoniae. Comparing with control, all experimental groups presented reduction of larger than 135 nm molecular size, but there was only significant difference with alteplase (p = 0,02). Viscosity reduced at all experimental groups, but increased at control. DNase group presented negative median (-5 mPa/s) of viscosity, and differed significantly from that observed in the control group (p = 0.04).

CONCLUSIONS

Alteplase, DNase and alteplase + DNase changed significantly physical and chemical properties of experimental empyema at fibrinopurulent phase: alteplase reduced molecular size larger than 135 nm and DNase reduced viscosity.

Targeting of plasminogen activator inhibitor 1 improves fibrinolytic therapy for tetracycline-induced pleural injury in rabbits

Endogenous active plasminogen activator inhibitor 1 (PAI-1) was targeted in vivo with monoclonal antibodies (mAbs) that redirect its reaction with proteinases to the substrate branch. mAbs were used as an adjunct to prourokinase (single-chain [sc] urokinase [uPA]) intrapleural fibrinolytic therapy (IPFT) of tetracycline-induced pleural injury in rabbits. Outcomes of scuPA IPFT (0.25 or 0.0625 mg/kg) with 0.5 mg/kg of mouse IgG or mAbs (MA-33H1F7 and MA-8H9D4) were assessed at 24 hours. Pleural fluid (PF) was collected at 0, 10, 20, and 40 minutes and 24 hours after IPFT and analyzed for plasminogen activating (PA), uPA, fibrinolytic activities, levels of total plasmin/plasminogen, α-macroglobulin (αM), mAbs/IgG antigens, free active uPA, and αM/uPA complexes. Anti-PAI-1 mAbs, but not mouse IgG, delivered with an eightfold reduction in the minimal effective dose of scuPA (from 0.5 to 0.0625 mg/kg), improved the outcome of IPFT (P < 0.05). mAbs and IgG were detectable in PFs at 24 hours. Compared with identical doses of scuPA alone or with IgG, treatment with scuPA and anti-PAI-1 mAbs generated higher PF uPA amidolytic and PA activities, faster formation of αM/uPA complexes, and slower uPA inactivation. However, PAI-1 targeting did not significantly affect intrapleural fibrinolytic activity or levels of total plasmin/plasminogen and αM antigens. Targeting PAI-1 did not induce bleeding, and rendered otherwise ineffective doses of scuPA able to improve outcomes in tetracycline-induced pleural injury. PAI-1-neutralizing mAbs improved IPFT by increasing the durability of intrapleural PA activity. These results suggest a novel, well-tolerated IPFT strategy that is tractable for clinical development.

Repeated therapeutic thoracentesis to manage complicated parapneumonic effusions

PURPOSE OF REVIEW

In complicated parapneumonic effusion (CPPE), antibiotics and evacuation of the infected pleural fluid are mandatory. The first-line evacuation treatment is still controversial. The aim of this article is to highlight the usefulness of repeated therapeutic thoracentesis (RTT) as a first-line treatment.

RECENT FINDINGS

In the most recent study on RTT in CPPE, disposable pleural needles were used and the median number of thoracentesis was 3. The success rate was 81%, and only 4% of the patients were referred for thoracic surgery. The 1-year survival rate was 88%. On multivariate analysis, the observation of microorganisms in the pleural fluid after Gram staining and first thoracentesis volume at least 450 ml was associated with a higher risk of RTT failure. RTT is less invasive and can target different loculated pleural collections. Patients are less confined to beds between each procedure, and could even be ambulatory managed. The use of intrapleural fibrinolytics in association with DNase could most likely enhance the efficacy of RTT.

SUMMARY

RTT is efficient and well tolerated in the management of CPPE, including pleural empyema, and could be proposed as a first-line therapy for CPPE. This technique could be used in association with intrapleural fibrinolytics and DNase.

The Use of Recombinant Tissue Plasminogen Activator (rTPA) in The Treatment of Fibrinous Pleuropneumonia in Horses: 25 Cases (2007-2012)

Background

Information about treatment protocols, adverse effects and outcomes with intrapleural recombinant tissue plasminogen activator (rTPA) use in horses with fibrinous pleuropneumonia is limited.

Hypothesis/Objectives

Describe factors that contribute to clinical response and survival of horses treated with rTPA intrapleurally.

Animals

Horses with bacterial pneumonia and fibrinous pleural effusion diagnosed by ultrasonography, that were treated with rTPA intrapleurally.

Methods

Retrospective multicenter case series from 2007–2012. Signalment, history, clinical and laboratory evaluation, treatment, and outcome obtained from medical records. Regression analysis used to identify associations between treatments and outcomes.

Results

Thirty three hemithoraces were treated in 25 horses, with 55 separate treatments. Recombinant tissue plasminogen activator (375–20,000 μg/hemithorax) was administered 1–4 times. Sonographically visible reduction in fibrin mat thickness, loculations, fluid depth, or some combination of these was seen in 32/49 (65%) treatments. Response to at least 1 treatment was seen in 17/20 (85%) horses with sonographic follow‐up evaluation after every treatment. Earlier onset of rTPA treatment associated with increased survival odds. No association was found between cumulative rTPA dose or number of rTPA doses and survival, development of complications, duration of hospitalization or total charges. Clinical evidence of hypocoagulability or bleeding was not observed. Eighteen horses (72%) survived to discharge.

Conclusions and clinical importance

Treatment with rTPA appeared safe and resulted in variable changes in fibrin quantity and organization within the pleural space. Recombinant tissue plasminogen activator could be a useful adjunct to standard treatment of fibrinous pleuropneumonia, but optimal case selection and dosing regimen remain to be elucidated.

Single-trocar thoracoscopy under local anesthesia for pleural space infection

OBJECTIVE

The role of single-trocar thoracoscopy for complicated parapneumonic effusion (CPE) and pleural empyema is not established as yet. The aim of this study was to report our experience and analyze the efficacy and safety of debridement by single-trocar thoracoscopy for the patients with CPE and multiloculated empyema.

METHODS

We performed a retrospective study reviewing the medical records of the patients treated parapneumonic effusion and multiloculated empyema by single-trocar thoracoscopy under local anesthesia at our department from January 2000 to December 2012.

RESULTS

A total 29 patients with CPE and multiloculated empyema were treated by single-trocar thoracoscopy. As the staging of pleural infection, class 5 and class 7 by Light classification were 21 and 8 patients, respectively. The onset of the symptom was on average 13.9 ± 11.7 days before the procedure. This procedure was successful in 23 of 29 patients (79.3%) without further operation under general anesthesia. Complication occurred in 1 case of 29 patients (3.4%). Six patients required subsequently the operation under general anesthesia, and one of the 6 patients died to multiple organ failure caused by sepsis. A microbiological diagnosis could be made in fifteen patients (51.7%).

CONCLUSIONS

Debridement by single-trocar thoracoscopy can be an acceptable approach as the first-line procedure in patients with CPE and empyema. This procedure can provide not only appropriate and expeditious treatment but also information of pleural cavity to decide indication for thoracotomy under general anesthesia.

Active α-macroglobulin is a reservoir for urokinase after fibrinolytic therapy in rabbits with tetracycline-induced pleural injury and in human pleural fluids

Intrapleural processing of prourokinase (scuPA) in tetracycline (TCN)-induced pleural injury in rabbits was evaluated to better understand the mechanisms governing successful scuPA-based intrapleural fibrinolytic therapy (IPFT), capable of clearing pleural adhesions in this model. Pleural fluid (PF) was withdrawn 0-80 min and 24 h after IPFT with scuPA (0-0.5 mg/kg), and activities of free urokinase (uPA), plasminogen activator inhibitor-1 (PAI-1), and uPA complexed with α-macroglobulin (αM) were assessed. Similar analyses were performed using PFs from patients with empyema, parapneumonic, and malignant pleural effusions. The peak of uPA activity (5-40 min) reciprocally correlated with the dose of intrapleural scuPA. Endogenous active PAI-1 (10-20 nM) decreased the rate of intrapleural scuPA activation. The slow step of intrapleural inactivation of free uPA (t1/2(β) = 40 ± 10 min) was dose independent and 6.7-fold slower than in blood. Up to 260 ± 70 nM of αM/uPA formed in vivo [second order association rate (kass) = 580 ± 60 M(-1)·s(-1)]. αM/uPA and products of its degradation contributed to durable intrapleural plasminogen activation up to 24 h after IPFT. Active PAI-1, active α2M, and α2M/uPA found in empyema, pneumonia, and malignant PFs demonstrate the capacity to support similar mechanisms in humans. Intrapleural scuPA processing differs from that in the bloodstream and includes 1) dose-dependent control of scuPA activation by endogenous active PAI-1; 2) two-step inactivation of free uPA with simultaneous formation of αM/uPA; and 3) slow intrapleural degradation of αM/uPA releasing active free uPA. This mechanism offers potential clinically relevant advantages that may enhance the bioavailability of intrapleural scuPA and may mitigate the risk of bleeding complications.

Fibrinolytic therapy for parapneumonic empyema during pregnancy

Pneumonia and parapneumonic complicated effusion during pregnancy is uncommon but poses potentially serious risks to both mother and fetus. Enzymatic debridement of the pleural cavity with fibrinolytic agents is a noninvasive option that can facilitate drainage and prevent the need for surgery. Herein, we describe the cases of two pregnant women with parapneumonic empyema who were successfully treated with intrapleural fibrinolytic therapy.

Effects of extracellular DNA on plasminogen activation and fibrinolysis

The increased levels of extracellular DNA found in a number of disorders involving dysregulation of the fibrinolytic system may affect interactions between fibrinolytic enzymes and inhibitors. Double-stranded (ds) DNA and oligonucleotides bind tissue-(tPA) and urokinase (uPA)-type plasminogen activators, plasmin, and plasminogen with submicromolar affinity. The binding of enzymes to DNA was detected by EMSA, steady-state, and stopped-flow fluorimetry. The interaction of dsDNA/oligonucleotides with tPA and uPA includes a fast bimolecular step, followed by two monomolecular steps, likely indicating slow conformational changes in the enzyme. DNA (0.1-5.0 μg/ml), but not RNA, potentiates the activation of Glu- and Lys-plasminogen by tPA and uPA by 480- and 70-fold and 10.7- and 17-fold, respectively, via a template mechanism similar to that known for fibrin. However, unlike fibrin, dsDNA/oligonucleotides moderately affect the reaction between plasmin and α(2)-antiplasmin and accelerate the inactivation of tPA and two chain uPA by plasminogen activator inhibitor-1 (PAI-1), which is potentiated by vitronectin. dsDNA (0.1-1.0 μg/ml) does not affect the rate of fibrinolysis by plasmin but increases by 4-5-fold the rate of fibrinolysis by Glu-plasminogen/plasminogen activator. The presence of α(2)-antiplasmin abolishes the potentiation of fibrinolysis by dsDNA. At higher concentrations (1.0-20 μg/ml), dsDNA competes for plasmin with fibrin and decreases the rate of fibrinolysis. dsDNA/oligonucleotides incorporated into a fibrin film also inhibit fibrinolysis. Thus, extracellular DNA at physiological concentrations may potentiate fibrinolysis by stimulating fibrin-independent plasminogen activation. Conversely, DNA could inhibit fibrinolysis by increasing the susceptibility of fibrinolytic enzymes to serpins.

Interventional management of pleural infections

Pleural infections represent an important group of disorders that is characterized by the invasion of pathogens into the pleural space and the potential for rapid progression to frank empyema. Previous epidemiologic studies have indicated that empyema is increasing in prevalence, which underscores the importance of urgent diagnosis and effective drainage to improve clinical outcomes. Unfortunately, limited evidence exists to guide clinicians in selecting the ideal drainage intervention for a specific patient because of the broad variation that exists in the intrapleural extent of infection, presence of locules, comorbid features, respiratory status, and virulence of the underlying pathogen. Moreover, many patients experience delays in both the recognition of infected pleural fluid and the initiation of appropriate measures to drain the pleural space. The present review provides an update on the pathogenesis and interventional therapy of pleural infections with an emphasis on the unique role of image-guided drainage with small-bore catheters.

Feline pyothorax - new insights into an old problem: part 2. Treatment recommendations and prophylaxis

Until recently, pyothorax in the cat has been generally considered to have a poor prognosis. However, it has become clear that most cats that survive the first 48 h following presentation can be successfully treated with aggressive medical management. In this second part of a two-part review, logical guidelines for the management of the disease are discussed, with particular emphasis on antimicrobial selection. Patient stabilisation and supportive care, techniques for pleural space drainage and lavage and indications for surgery are reviewed.