The increasing incidence of empyema

Empyema caused by Streptococcus constellatus in a patient infected with HIV: a case report and literature review

BACKGROUND

Empyema caused by Streptococcus constellatus (S. constellatus) is rare in patients with HIV. To analyze the clinical data of a patient living with HIV (PLHIV), who got empyema caused by S. constellatus, investigating the diagnosis and treatment of this disease through literature review to improve the clinical understanding of this disease.

CASE PRESENTATION

We have reported here a 58-year-old male PLHIV with cough, wheezing, and fever for 20 days. He has a history type 2 diabetes, alcohol abuse, and a teeth extracted. Chest computed tomography revealed multiple encapsulated pleural effusions, pneumatosis, and partial compressive atelectasis in the right lung. Submission of pleural efusions timely, and then cultures revealed S. constellatus. After comprehensive treatment, including antibiotics, closed pleural drainage, and intrapleural injection of urokinase, the pleural efusion was absorbed, and chest computed tomography also confirmed the improvement.

CONCLUSIONS

S. constellatus should not be neglected as a pus pathogen in patients with HIV. comprehensive treatment is important for empyema of S. constellatus.

Targeting the PAI-1 Mechanism with a Small Peptide Increases the Efficacy of Alteplase in a Rabbit Model of Chronic Empyema

The incidence of empyema is increasing and associated with a mortality rate of 20% in patients older than 65 years. Since 30% of patients with advanced empyema have contraindications to surgical treatment, novel, low-dose, pharmacological treatments are needed. A Streptococcus pneumoniae-induced rabbit model of chronic empyema recapitulates the progression, loculation, fibrotic repair, and pleural thickening of human disease. Treatment with single chain (sc) urokinase (scuPA) or tissue type (sctPA) plasminogen activators in doses 1.0-4.0 mg/kg were only partially effective in this model. Docking Site Peptide (DSP; 8.0 mg/kg), which decreased the dose of sctPA for successful fibrinolytic therapy in acute empyema model did not improve efficacy in combination with 2.0 mg/kg scuPA or sctPA. However, a two-fold increase in either sctPA or DSP (4.0 and 8.0 mg/kg or 2.0 and 16.0 mg/kg sctPA and DSP, respectively) resulted in 100% effective outcome. Thus, DSP-based Plasminogen Activator Inhibitor 1-Targeted Fibrinolytic Therapy (PAI-1-TFT) of chronic infectious pleural injury in rabbits increases the efficacy of alteplase rendering ineffective doses of sctPA effective. PAI-1-TFT represents a novel, well-tolerated treatment of empyema that is amenable to clinical introduction. The chronic empyema model recapitulates increased resistance of advanced human empyema to fibrinolytic therapy, thus allowing for studies of muti-injection treatments.

Pleural Empyema Due to Proteus Mirabilis in an Adult: A Rarely Encountered Clinical Scenario

The presence of Proteus species in the pleural space is an uncommonly reported entity and is rarely seen even in patients with compromised immune status. We report a case of pleural empyema due to Proteus species in an adult oral cancer patient receiving chemotherapy for academic interest and for generating awareness regarding an expanded pathogenic spectrum of the organism. A 44-year-old salesman, non-smoker and non-alcoholic, presented with sudden-onset shortness of breath, left-sided chest pain, and low-grade fever of one-day duration. He had been recently diagnosed with adenocarcinoma of the tongue and had received two cycles of chemotherapy. After clinical and radiographic evaluation, the patient was diagnosed with left-sided empyema. Following thoracocentesis, the aspirated pus sent for bacterial culture yielded pure growth of Proteus mirabilis. Appropriately modified antibiotic therapy with parenteral piperacillin-tazobactam followed by cefixime, tube drainage, and other supportive therapy resulted in a favorable outcome. After three weeks of hospitalization, the patient was discharged for further planned management of his underlying condition. Though uncommon, the possibility of Proteus species should be kept in mind as a causative agent of thoracic empyema in adults, especially in immunocompromised patients with cancer, diabetes, and renal diseases. The so-called common microorganisms of empyema appear to have altered over time, influenced by anticancer therapy and underlying host immune status. Rapid diagnosis and appropriate antimicrobial therapy usually result in a favorable outcome.

Epidemiology of pediatric parapneumonic pleural effusion during 13-valent pneumococcal conjugate vaccine implementation

INTRODUCTION

The reported incidence of parapneumonic pleural effusion, including empyema, has shown fluctuations in the last decades. It has been related to the implementation of different types of conjugate pneumococcal vaccines.

METHODS

We have retrospectively reviewed data from all 10 public hospitals in Alicante Province (Spain) covering a population of 279,000 children under 15 years of age, between 2010 and 2018. Effusions less than 10 mm (PE-) and those of 10 mm or more (PE+) were separated.

RESULTS

A total of 366 episodes of parapneumonic pleural effusion have been analyzed, 178 PE- (48.6%) and 188 PE+ (51.4%), with a median age of 4 years (interquartile range: 2-7 years) and marked seasonality with the maximum in winter and the minimum in summer. A culture proven bacterial agent was identified in 34 patients (9.3%), mainly Streptococcus pneumoniae (24 patients) followed by Streptococcus pyogenes (7 patients). The most frequent S. pneumoniae serotype was 19A (6 patients) and 3 vaccine failures were observed. The mean annual incidence rate was 14.3 cases per 100,000 children under 15 years of age (7.0 for PE- and 7.3 for PE+). No significant changes were observed in incidence over time, but noticeable differences in incidence were observed in different health departments.

CONCLUSIONS

We have not found temporal variations in incidence of parapneumonic effusion despite the implementation of the 13-valent pneumococcal conjugate vaccine. The unexplained disparity in incidence between close departments is noteworthy.

Management of Empyema Thoracis in Low-Resource Settings

Most cases of empyema thoracis are sequelae of severe pneumonia, but chest trauma and complications of chest tube insertion as cause are not uncommon in low-resource settings. Diagnosis is usually delayed due to delayed presentation to health care facilities, low index of suspicion among health care professionals, and inability to properly stage the disease with the available diagnostic tools. Early use of antibiotics and appropriate-sized and well-placed chest tube drainage is associated with good outcomes at a decreased cost. Surgical management of empyema thoracis is indicated when chest tube drainage and antibiotic treatment fail to achieve complete resolution.

Surgical Management of Pneumothorax and Pleural Space Disease

Pleural space diseases constitute a wide range of benign and malignant conditions, including pneumothorax, pleural effusion and empyema, chylothorax, pleural-based tumors, and mesothelioma. The focus of this article is the surgical management of the 2 most common pleural disorders seen in modern thoracic surgery practice: spontaneous pneumothorax and empyema.

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.

Clinico-radiological profile of the patients with empyema thoracis: A prospective analytical study

BACKGROUND

Empyema thoracis is defined as the presence of pus in the pleural cavity and carries significant morbidity and mortality. This study aimed to explore the demographic and clinico-radiological characteristics of patients with empyema thoracis.

MATERIAL AND METHODS

The present study was conducted in a tertiary care teaching hospital in North India. The patients diagnosed with empyema thoracis were included in the study. Demographic, etiologic, clinical, radiographic, and outcome data were prospectively collected and analyzed.

RESULTS

The study included 48 patients. The median age of empyema thoracis patients was 37(IQR 26-45) years. Common presenting symptoms were breathlessness (n = 37,77%) and chest pain (n = 34,70%). Contrast-enhanced computed tomography (CECT) of the chest showed type III empyema in 52% (21) patients followed by type 1 and type II in 25% and 22%, respectively. CECT thorax showed the collapse of lung and consolidation in (n = 28, 70%) and (n = 24, 60%) patients, respectively. All the patients, except for one, were managed with underwater seal intercostal tube drainage (ICD) procedure for the management of empyema. The median time to remove the ICD tube among 35 patients was 14 (IQR 9-21) days. Forty patients (83.3%) responded to the treatment and were discharged. Eight patients (16.7%) deteriorated and succumbed to the disease.

CONCLUSION

Patients of empyema thoracis required a prolonged period of chest tube drainage and carried significant morbidity and mortality.

Surveillance of pediatric parapneumonic effusion/empyema in New Zealand

AIM

The incidence of childhood empyema has been increasing in some developed countries despite the introduction of pneumococcal vaccination. This study aimed to document the incidence, bacterial pathogens, and morbidity/mortality of parapneumonic effusion/empyema in New Zealand.

METHODS

A prospective study of 102 children <15 years of age requiring hospitalization with parapneumonic effusion/empyema between May 1, 2014 and May 31, 2016 notified via the New Zealand Paediatric Surveillance Unit. Parapneumonic effusion/empyema was defined as pneumonia and pleural effusion persisting ≥7 days, and/or any pneumonia, and pleural effusion necessitating drainage. Notifying pediatricians completed standardized questionnaires.

RESULTS

Annual pediatric parapneumonic effusion/empyema incidence was 5.6/100,000 (95% confidence interval [CI]: 4.7-6.9). Most children (80%) required surgical intervention and 31% required intensive care. A causative organism was identified in 71/102 (70%) cases. Although Staphylococcus aureus (25%) and Streptococcus pneumoniae (25%) infection rates were equal, prolonged hospitalization and intensive care admission were more common in children with S. aureus PPE/E. Māori and Pasifika children were over-represented at 2.2 and 3.5 times, their representation in the New Zealand pediatric population. Pneumococcal vaccination was incomplete, with only 61% fully immunized and 30% unimmunized. Haemophilus influenzae type b vaccine uptake was near complete at 89/94 (95%), with influenza immunization only 3/78 (4%).

CONCLUSIONS

New Zealand has a high incidence of pediatric complicated parapneumonic effusion/empyema with significant morbidity. S. aureus was a significant cause of severe empyema in New Zealand, particularly for Māori and Pasifika children. Improvements in vaccine coverage are needed along with strategies to reduce S. aureus disease morbidity.

Lung Decortication With Argon Plasma Energy for the Treatment of Chronic Pleural Empyema

Lung decortication for the treatment of chronic pleural empyema remains a technically challenging procedure that is associated with bleeding and air leak. The recent advent of pure argon plasma has provided thoracic surgeons with an electrically neutral energy source for dissection and coagulation of pulmonary tissue with minimal depth of necrosis. In this article, we describe the technique of lung decortication with argon plasma energy (PlasmaJet, Plasma Surgical, Roswell, GA, USA) for the treatment of chronic pleural empyema. With appropriate application, the PlasmaJet can facilitate the removal of fibrous cortex with satisfactory hemostasis and aerostasis. Argon plasma energy can potentially be a useful adjunct in lung decortication. Controlled trials are needed to determine its role in the surgical management of advanced pleural empyema.

The Association Between Pleural Empyema and Peripheral Arterial Disease in Younger Patients: A Retrospective National Population-Based Cohort Study

Background: To investigate the relationship between pleural empyema (PE) and peripheral arterial disease (PAD).

Methods: We conducted a retrospective cohort study using data from the National Health Institute Research Database. Univariable and multivariable Cox's proportional hazard regressions were performed to investigate the association between PE and the risk of PAD. Kaplan–Meier method and the differences were assessed using a log-rank test.

Results: The overall incidence of PAD was higher in the PE cohort than in the non-PE cohort (2.76 vs. 1.72 per 1,000 person-years) with a crude hazard ratio (HR) of 1.61 [95% confidence interval (CI) = 1.41–1.83]. After adjustment for age, gender, and comorbidities, patients with PE were noted to be associated with an increased risk of PAD compared with those without PE [adjusted HR (aHR) = 1.18, 95% CI = 1.03–1.35]. Regarding the age-specific comparison between the PE and non-PE cohorts, PAD was noted to be significantly high in the ≤ 49 years age group (aHR = 5.34, 95% CI = 2.34–10.1). The incidence of PAD was higher in the first 2 years, with an aHR of 1.35 (95% CI = 1.09–1.68) for patients with PE compared with those without PE.

Conclusion: The risk of PAD was higher if patients with PE were younger than 49 years and within the 2-year diagnosis of PE.

Empyema with fistula successfully treated with a comprehensive approach including bronchial blocker and embolization receiving veno-venous extracorporeal membrane oxygenation

Background

Complicated empyema accompanied by bronchopleural fistula (BPF) has high mortality. The treatment strategy for severe respiratory failure due to empyema with BPF has yet to be established.

Case Presentation

A 70-year-old man was brought to our hospital and diagnosed with right empyema, BPF (at bronchi B4-10), and secondary left pneumonia. We initiated drainage followed by veno-venous extracorporeal membrane oxygenation due to the severe hypoxia. First, the patient underwent endoscopic treatment with obstructive materials (known as endobronchial Watanabe spigot [EWS]) at B8-10, and was weaned off veno-venous extracorporeal membrane oxygenation on day 7. A secondary EWS was carried out at B4-6. A combination of medical treatments (drainage, antibiotics, nutritional therapy, and rehabilitation) improved his general condition. The patient was able to leave the hospital on foot.

Conclusion

A comprehensive approach could explain the success of the medical treatment. The principal components are the repeated application of EWS as damage control.

Inhibitory Effect of the Traditional Chinese Medicine Ephedra sinica granules on Streptococcus pneumoniae Pneumolysin

Streptococcus pneumoniae (S. pneumoniae) is an opportunistic pathogen that causes pneumonia, meningitis and bacteremia in humans and animals. Pneumolysin (PLY), a major pore-forming toxin that is important for S. pneumoniae pathogenicity, is a promising target for the development of anti-infective agents. Ephedra sinica granules (ESG) is one of the oldest medical preparation with multiple biological activities (such as a divergent wind and cold effect); however, the detailed mechanism remains unknown. In this study, we found that ESG treatment significantly inhibited the oligomerization of PLY and then reduced the activity of PLY without affecting S. pneumoniae growth and PLY production. In a PLY and A549 cell co-incubation system, the addition of ESG resulted in significant protection against PLY-mediated cell injury. Furthermore, S. pneumoniae-infected mice showed decreased mortality, and alleviated tissue damage and inflammatory reactions following treatment with ESG. Our results indicate that ESG is a potential candidate treatment for S. pneumoniae infection that targets PLY. This finding partially elucidates the mechanism of the Chinese herbal formula ESG in the treatment of pneumococcal disease.

COMPLICATED PNEUMONIA WITH EMPYEMA CAUSED BY STREPTOCOCCUS ANGINOSUS IN A CHILD

Objective:

To highlight the pathogenicity of Streptococcus anginosus, which is rare in pediatric patients, but can cause severe infections that are known to have a better outcome when treated early with interventional procedures and prolonged antibiotic therapy.

Case

description: The patient is a 6-year-old boy with global developmental delay, examined in the emergency room due to fever and respiratory distress. The physical examination and diagnostic workout revealed complicated pneumonia with empyema of the left hemithorax; he started antibiotic therapy and underwent thoracic drainage. Pleural fluid cultures grew Streptococcus anginosus. On day 11, the child had a clinical deterioration with recurrence of fever, hypoxia, and respiratory distress. At this point, considering the causative agent, he was submitted to video-assisted thoracoscopic decortication, with good progress thereafter.

Comments:

Streptococcus anginosus is a commensal bacterium of the human oral cavity capable of causing severe systemic infections. Although reports of complicated thoracic infections with this agent are rare in the pediatric population, they have been increasing in adults. Streptococcus anginosus has a high capacity to form abscess and empyema, requiring different therapeutic approaches when compared to complicated pneumonia caused by other agents.

Increase in Streptococcus pneumoniae serotype 3 associated parapneumonic pleural effusion/empyema after the introduction of PCV13 in Germany

INTRODUCTION

Pediatric pneumococcal pneumonia complicated by parapneumonic pleural effusion/empyema (PPE/PE) remains a major concern despite general immunization with pneumococcal conjugate vaccines (PCVs).

METHODS

In a nationwide pediatric hospital surveillance study in Germany we identified 584 children <18 years of age with bacteriologically confirmed PPE/PE from October 2010 to June 2018. Streptococcus pneumoniae was identified by culture and/or PCR of blood samples and/or pleural fluid and serotyped.

RESULTS

S. pneumoniae was identified in 256 of 584 (43.8%) children by culture (n = 122) and/or PCR (n = 207). The following pneumococcal serotypes were detected in 114 children: serotype 3 (42.1%), 1 (25.4%), 7F (12.3%), 19A (7.9%), other PCV13 serotypes (4.4%) and non-PCV13 serotypes (7.9%). Between October 2010 and June 2014 serotype 1 (38.1%) and serotype 3 (25.4%) were most prevalent, whereas between July 2014 and June 2018 serotype 3 (62.7%) and non-PCV13 serotypes (15.7%) were dominant. Compared to children with other pneumococcal serotypes, children with serotype 3 associated PPE/PE were younger (median 3.2 years [IQR 2.1-4.3 years] vs. median 5.6 years [IQR 3.8-8.2 years]; p < 0.001) and more frequently admitted to intensive care (43 [89.6%] vs. 48 [73.8%]; p = 0.04). Seventy-six of 114 (66.7%) children with pneumococcal PPE/PE had been vaccinated with pneumococcal vaccines. Thirty-nine of 76 (51.3%) had received a vaccine covering the serotype detected. Thirty of these 39 breakthrough cases were age-appropriately vaccinated with PCV13 and considered vaccine failures, including 26 children with serotype 3, three children with serotype 19A and one child with serotype 1.

CONCLUSION

Following the introduction of PCV13 in general childhood vaccination we observed a strong emergence of serotype 3 associated PPE/PE in the German pediatric population, including a considerable number of younger children with serotype 3 vaccine breakthrough cases and failures. Future PCVs should not only cover newly emerging serotypes, but also include a more effective component against serotype 3.

Predictors and Clinical Outcomes in Empyema Thoracis Patients Presenting to the Emergency Department Undergoing Video-Assisted Thoracoscopic Surgery

Background: Video-assisted thoracoscopic surgery (VATS) is widely used for the treatment of empyema. We evaluated clinical symptoms, laboratory examinations, and thoracentesis to assess patients in the emergency department (ED) with empyema thoracis, undergoing VATS to identify predictors of adverse outcomes. Methods: This retrospective study was conducted by reviewing records of ED patients with pleural empyema admitted for VATS from January 2007 to June 2014. Demographic data, clinical symptoms, and laboratory examinations were compared for survivors (Group I) and non-survivors (Group II). Logistic regression analysis was used to identify parameters related to postoperative mortality. Results: From 380 patients, 7.6% (n = 29) died postoperatively. Survivors and non-survivors exhibited differences in age, gender, presence of cough, dyspnea, chest pain, empyema stage, cerebrovascular disease, malignancy, the glucose level of pleural fluid, serum hemoglobin, platelet count, blood urea nitrogen, and potassium levels. The logistic analysis demonstrated that the most significant factor related to the postoperative morbidity is chest pain (p = 0.018). Conclusions: VATS could be a safe option for pediatric and geriatric patients. Age does not appear to affect postoperative mortality. A high degree of awareness is essential for perioperative management and early surgical treatment when ED patients present with the clinical symptom of chest pain.

Clinical, functional, and radiological outcome in children with pleural empyema

INTRODUCTION

Few studies have prospectively evaluated recovery process and long-term consequences of pleural space infections.

OBJECTIVE

To evaluate clinical, pulmonary, and diaphragmatic function and radiological outcome in patients hospitalized with pleural empyema.

MATERIAL AND METHODS

Previously healthy patients from 6 to 16 years were enrolled. Demographic, clinical, and treatment data were registered. At hospital discharge, and every 30 days or until normalization, patients underwent a clinical evaluation, diaphragmatic ultrasound, and lung function testing. Chest radiographs were performed at subsequent visits only if abnormalities persisted.

RESULTS

Thirty patients were included. Nineteen (63%) were male, with an age of (mean ± SD) 9.7 ± 3.2 years, and body mass index (mean ± SD) 18.6 ± 3. Twelve patients (40%) were treated with chest tube drainage only, 12 (40%) exclusively with surgery, and 6 (20%) completed treatment with surgery due to an ineffective chest tube drainage. At hospital discharge, 26 (87%) of patients had abnormal breath sounds at the site of infection, 28 (93%) had a spirometric restrictive pattern, 19 (63%) diaphragmatic motion impairment, and 29 (97%) presented radiological involvement of pleural space, mainly pleural thickening. All patients had recovered diaphragmatic motion and were asymptomatic at 90- and 120-day follow-up control, respectively. Then, with a great individual variability, radiological findings, and lung function returned to normal at 60 days (range 30-180) and 90 days (range 30-180) after hospital discharge, respectively.

CONCLUSION

Patients with pleural empyema had a complete and progressive recovery, with initial clinical and diaphragmatic motion normalization followed by radiological and lung function recovery.

Emerging concepts in pleural infection

PURPOSE OF REVIEW

Pleural infection remains an important pulmonary disease, causing significant morbidity and mortality. There is a resurgence of disease burden despite introduction of antibiotics and pneumococcal vaccines. A revisit of the pathogenesis and update on intervention may improve the care of pleural infection.

RECENT FINDINGS

Recent studies have uncovered the prognostic implication of the presence of a pleural effusion in patients with pneumonia. Identifying where the bacteria lives may have diagnostic and therapeutic implications. Over-exaggerated pleural inflammation may underlie development of parapneumonic effusion as indirect evidence and a randomized study in children raised a role of corticosteroids in parapneumonic pleural effusions, but data are lacking for adults. Optimization of the delivery regimen of intrapleural fibrinolytic and deoxyribonuclease therapy is ongoing.

SUMMARY

The review aims to review the current practice and explore new directions of treatment on pleural infection.

Bacteriology and clinical outcomes of patients with culture-positive pleural infection in Western Australia: A 6-year analysis

BACKGROUND AND OBJECTIVE

Pleural infection is a clinical challenge; its microbiology can be complex. Epidemiological and outcome data of pleural infection in adult Australians are lacking. We describe the bacteriology and clinical outcomes of Australian adults with culture-positive pleural infection (CPPI) over a 6-year period.

METHODS

Cases with CPPI were identified through Western Australian public hospitals electronic record. Culture isolates, admission dates, vital status, co-morbidities, radiology, blood and pleural fluid tests were extracted.

RESULTS

In total, 601 cases (71.4% males; median age: 63 years (IQR: 50-74); median hospital stay 13 days) involving 894 bacterial isolates were identified. Hospital-acquired (HA)-CPPI was defined in 398 (66.2%) cases, community-acquired (CA)-CPPI in 164 (27.3%) cases and the remaining classified as oesophageal rupture/leak. Co-morbidities, most frequently cancer, were common (65.2%). Radiological evidence of pneumonia was present in only 43.8% of CA-CPPI and 27.3% of HA-CPPI. Of the 153 different bacterial strains cultured, Streptococcus species (32.9%) especially viridans streptococci group were most common in CA-CPPI, whereas HA-CPPI was most often associated with Staphylococcus aureus (11.6%) and Gram-negative (31.9%) infections. Mortality was high during hospitalization (CA-CPPI 13.4% vs HA-CPPI 16.6%; P = 0.417) and at 1 year (CA-CPPI 32.4% vs HA-CPPI 45.5%; P = 0.006).

CONCLUSION

This is the first large multicentre epidemiological study of pleural infection in Australian adults and includes the largest cohort of HA-CPPI published to date. CPPI is caused by a diverse range of organisms which vary between CA and HA sources. CPPI is a poor prognostic indicator both in the short term and in the subsequent 12 months.

Whole Exome Sequencing Identifies New Host Genomic Susceptibility Factors in Empyema Caused by Streptococcus pneumoniae in Children: A Pilot Study

Pneumonia is the leading cause of death amongst infectious diseases. Streptococcus pneumoniae is responsible for about 25% of pneumonia cases worldwide, and it is a major cause of childhood mortality. We carried out a whole exome sequencing (WES) study in eight patients with complicated cases of pneumococcal pneumonia (empyema). An initial assessment of statistical association of WES variation with pneumonia was carried out using data from the 1000 Genomes Project (1000G) for the Iberian Peninsula (IBS) as reference controls. Pseudo-replication statistical analyses were carried out using different European control groups. Association tests pointed to single nucleotide polymorphism (SNP) rs201967957 (gene MEIS1; chromosome 2; p-value_IBS = 3.71 × 10^-13) and rs576099063 (gene TSPAN15; chromosome 10; p-value_IBS = 2.36 × 10^-8) as the best candidate variants associated to pneumococcal pneumonia. A burden gene test of pathogenicity signaled four genes, namely, OR9G9, MUC6, MUC3A and APOB, which carry significantly increased pathogenic variation when compared to controls. By analyzing various transcriptomic data repositories, we found strong supportive evidence for the role of MEIS1, TSPAN15 and APOBR (encoding the receptor of the APOB protein) in pneumonia in mouse and human models. Furthermore, the association of the olfactory receptor gene OR9G9 has recently been related to some viral infectious diseases, while the role of mucin genes (MUC6 and MUC3A), encoding mucin glycoproteins, are well-known factors related to chronic obstructive airway disease. WES emerges as a promising technique to disentangle the genetic basis of host genome susceptibility to infectious respiratory diseases.

Real-time ultrasound-guided pigtail catheter chest drain for complicated parapneumonic effusion and empyema in children - 16-year, single-centre experience of radiologically placed drains

BACKGROUND

Chest tube drainage with fibrinolytics is a cost-effective treatment option for parapneumonic effusion and empyema in children. Although the additional use of ultrasound (US) guidance is recommended, this is rarely performed in real time to direct drain insertion.

OBJECTIVE

To evaluate the effectiveness and safety of real-time US-guided, radiologically placed chest drains at a tertiary university hospital.

MATERIALS AND METHODS

This was a retrospective review over a 16-year period of all children with parapneumonic effusion or empyema undergoing percutaneous US-guided drainage at our centre.

RESULTS

Three hundred and three drains were placed in 285 patients. Treatment was successful in 93% of patients after a single drain (98.2% success with 2 or 3 drains). Five children had peri-insertion complications, but none was significant. The success rate improved with experience. Although five patients required surgical intervention, all children treated since 2012 were successfully treated with single-tube drainage only and none has required surgery.

CONCLUSION

Our technique for inserting small-bore (≤8.5 F) catheter drains under US guidance is effective and appears to be a safe procedure for first-line management of complicated parapneumonic effusion and empyema.

Human pleural fluid is a potent growth medium for Streptococcus pneumoniae

Empyema is defined by the presence of bacteria and/or pus in pleural effusions. However, the biology of bacteria within human pleural fluid has not been studied. Streptococcus pneumoniae is the most common cause of pediatric and frequent cause of adult empyema. We investigated whether S. pneumoniae can proliferate within human pleural fluid and if growth is affected by the cellular content of the fluid and/or characteristics of pneumococcal surface proteins. Invasive S. pneumoniae isolates (n = 24) and reference strain recovered from human blood or empyema were inoculated (1.5×10⁶CFU/mL) into sterile human malignant pleural fluid samples (n = 11). All S. pneumoniae (n = 25) strains proliferated rapidly, increasing by a median of 3009 (IQR 1063–9846) from baseline at 24hrs in all pleural effusions tested. Proliferation was greater than in commercial pneumococcal culture media and concentrations were maintained for 48hrs without autolysis. A similar magnitude of proliferation was observed in pleural fluid before and after removal of its cellular content, p = 0.728. S. pneumoniae (D39 strain) wild-type, and derivatives (n = 12), each with mutation(s) in a different gene required for full virulence were inoculated into human pleural fluid (n = 8). S. pneumoniae with pneumococcal surface antigen A (ΔpsaA) mutation failed to grow (2207-fold lower than wild-type), p<0.001, however growth was restored with manganese supplementation. Growth of other common respiratory pathogens (n = 14) across pleural fluid samples (n = 7) was variable and inconsistent, with some strains failing to grow. We establish for the first time that pleural fluid is a potent growth medium for S. pneumoniae and proliferation is dependent on the PsaA surface protein and manganese.

Population-based cohort study investigating the correlation of diabetes mellitus with pleural empyema in adults in Taiwan

We assessed the association between diabetes mellitus and the risk of pleural empyema in Taiwan.A population-based retrospective cohort study was conducted using the database of the Taiwan National Health Insurance Program. There were 28,802 subjects aged 20 to 84 years who were newly diagnosed with diabetes mellitus from 2000 to 2010 as the diabetes group and 114,916 randomly selected subjects without diabetes mellitus as the non-diabetes group. The diabetes group and the non-diabetes group were matched by sex, age, comorbidities, and the year of index date. The incidence of pleural empyema at the end of 2011 was estimated. A multivariable Cox proportional hazards regression model was used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) for pleural empyema associated with diabetes mellitus.The overall incidence of pleural empyema was 1.65-fold higher in the diabetes group than that in the non-diabetes group (1.58 vs 0.96 per 10,000 person-years, 95% CI 1.57-1.72). After adjusting for confounders, a multivariable Cox proportional hazards regression model revealed that the adjusted HR of pleural empyema was 1.71 in subjects with diabetes mellitus (95% CI 1.16-2.51), compared with those without diabetes mellitus. In further analysis, even in the absence of any comorbidity, the adjusted HR was 1.99 for subjects with diabetes mellitus alone (95% CI 1.18-3.38).Diabetic patients confer a 1.71-fold increased hazard of developing pleural empyema. Even in the absence of any comorbidity, the risk remains existent.

Targeting plasminogen activator inhibitor-1 in tetracycline-induced pleural injury in rabbits

Elevated active plasminogen activator inhibitor-1 (PAI-1) has an adverse effect on the outcomes of intrapleural fibrinolytic therapy (IPFT) in tetracycline-induced pleural injury in rabbits. To enhance IPFT with prourokinase (scuPA), two mechanistically distinct approaches to targeting PAI-1 were tested: slowing its reaction with urokinase (uPA) and monoclonal antibody (mAb)-mediated PAI-1 inactivation. Removing positively charged residues at the "PAI-1 docking site" (¹⁷⁹RHRGGS¹⁸⁴→¹⁷⁹AAAAAA¹⁸⁴) of uPA results in a 60-fold decrease in the rate of inhibition by PAI-1. Mutant prourokinase (0.0625-0.5 mg/kg; n = 12) showed efficacy comparable to wild-type scuPA and did not change IPFT outcomes ( P > 0.05). Notably, the rate of PAI-1-independent intrapleural inactivation of mutant uPA was 2 times higher ( P < 0.05) than that of the wild-type enzyme. Trapping PAI-1 in a "molecular sandwich"-type complex with catalytically inactive two-chain urokinase with Ser¹⁹⁵Ala substitution (S195A-tcuPA; 0.1 and 0.5 mg/kg) did not improve the efficacy of IPFT with scuPA (0.0625-0.5 mg/kg; n = 11). IPFT failed in the presence of MA-56A7C10 (0.5 mg/kg; n = 2), which forms a stable intrapleural molecular sandwich complex, allowing active PAI-1 to accumulate by blocking its transition to a latent form. In contrast, inactivation of PAI-1 by accelerating the active-to-latent transition mediated by mAb MA-33B8 (0.5 mg/kg; n = 2) improved the efficacy of IPFT with scuPA (0.25 mg/kg). Thus, under conditions of slow (4-8 h) fibrinolysis in tetracycline-induced pleural injury in rabbits, only the inactivation of PAI-1, but not a decrease in the rate of its reaction with uPA, enhances IPFT. Therefore the rate of fibrinolysis, which varies in different pathologic states, could affect the selection of PAI-1 inhibitors to enhance fibrinolytic therapy.

Accuracy of complement activation product levels to detect infected pleural effusion in rats

BACKGROUND

Pleural empyema is a well-known complication of pneumonia. If treatment is delayed, empyema may increase morbidity and mortality in affected patients. Therefore, the identification of empyema biomarkers in parapneumonic pleural effusion is desirable. Previous research has suggested complement activation products as candidate empyema markers.

OBJECTIVE

To compare the levels of complement activation products C3a, C5a, and C5b9 in pleural effusion induced by Staphylococcus aureus (SA), Streptococcus pneumoniae (SP), or turpentine (control).

METHODS

Thirty-nine male Wistar rats (mean weight 414 g; 290-546 g) were allocated as follows: 17 animals in the SA group, 12 in the SP group, and 10 in the control group. Bacteria or turpentine were injected into the pleural space. After 12 hr, intrapleural fluid was collected using ultrasound-guided thoracentesis. Levels of complement activation products were determined using ELISA kits.

RESULTS

Two SA and one SP animals died before 12 hr. Mean levels were as follows: C3a: 1066.82 µg/ml (937.29-1196.35 µg/ml) in SA, 1188.28 µg/ml (1095.65-1280.92 µg/ml) in SP, and 679.13 µg/ml (601.29-756.98 µg/ml) in controls (P < 0.001); C5a: 55.727 ng/ml (41.22-70.23 ng/ml) in SA, 520.107 ng/ml (278.92-761.3 ng/ml) in SP, and 5.268 ng/ml (1.68-8.85 ng/ml) in controls (P < 0.001); C5b9: 15.02 ng/ml (13.1-16.94 ng/ml) in SA, 16.63 ng/ml (14.37-18.9 ng/ml) in SP, and 14.05 ng/ml (9.8-18.29 ng/ml) in controls (P = 0.692). ROC analysis revealed an area under the curve of 0.987 (95% CI: 0.953-1) for C3a; 1 (1-1) for C5a; and 0.757 for C5b9 (0.523-0.990).

CONCLUSIONS

In the present rat model, complement activation fragments C3a and C5a accurately detected infected pleural effusion. Pediatr Pulmonol. 2017;52:757-762. © 2017 Wiley Periodicals, Inc.

Prevention of Community-Acquired Pneumonia with Available Pneumococcal Vaccines

Community-acquired pneumonia (CAP) places a considerable burden on society. A substantial number of pediatric and adult CAP cases are due to Streptococcus pneumoniae, but fortunately there are effective vaccines available that have a significant impact on CAP-related medical, social, and economic problems. The main aim of this paper is to evaluate the published evidence concerning the impact of pneumococcal vaccines on the prevention of CAP in children and adults. Available data indicate that pneumococcal conjugate vaccines (PCVs) are effective in children, reducing all-cause CAP cases and bacteremic and nonbacteremic CAP cases. Moreover, at least for PCV7 and PCV13, vaccination of children is effective in reducing the incidence of CAP among adults. Recently use of PCV13 in adults alone or in combination with the pneumococcal polysaccharide vaccine has been suggested and further studies can better define its effectiveness in this group of subjects. The only relevant problem for PCV13 is the risk of a second replacement phenomenon, which might significantly reduce its real efficacy in clinical practice. Protein-based pneumococcal vaccines might be a possible solution to this problem.

Multiple liver abscesses and bacteremia caused by Streptococcus constellatus infection: a case report

The Streptococcus milleri group (SMG) comprises commensal mucosal bacteria. Pyogenic liver abscesses due to hematogenous SMG infection are rare but can be observed even in healthy patients. In such cases, physicians should consider the existence of primary lesions that allow penetration of the SMG.

Microbiological Characteristics and Predictive Factors for Mortality in Pleural Infection: A Single-Center Cohort Study in Korea

Background

Identification and understanding of the pathogens responsible for pleural infection is critical for appropriate antibiotic treatment. This study sought to determine the microbiological characteristics of pleural infection and to identify potential predictive factors associated with mortality.

Methods

In this retrospective study, we analyzed patient data from 421 cases of parapneumonic effusion. A total of 184 microorganisms were isolated from 164 patients, using two culture systems: a standard method and a method using pairs of aerobic and anaerobic blood culture bottles.

Results

The most frequently isolated microorganisms were streptococci (31.5%), followed by staphylococci (23.4%), gram-negative bacteria (18.5%) and anaerobes (10.3%). Streptococci were the main microorganisms found in standard culture (41.9%) and community-acquired infections (52.2%), and were susceptible to all antimicrobial agents in drug sensitivity testing. Staphylococci were the most frequently isolated pathogens in blood cultures (30.8%) and hospital-acquired infections (38.3%), and were primarily multidrug-resistant (61.8%). In multivariate analysis, the following were significant predictive factors for 30-day mortality among the total population: CURB-65 ≥ 2 (aOR 5.549, 95% CI 2.296–13.407, p<0.001), structural lung disease (aOR 2.708, 95% CI 1.346–5.379, p = 0.004), PSI risk class IV-V (aOR 4.714, 95% CI 1.530–14.524, p = 0.007), no use of intrapleural fibrinolytics (aOR 3.062, 95% CI 1.102–8.511, p = 0.014), hospital-acquired infection (aOR 2.205, 95% CI 1.165–4.172, p = 0.015), age (aOR 0.964, 95% CI 0.935–0.994, p = 0.018), and SOFA score ≥2 (aOR 2.361, 95% CI 1.134–4.916, p = 0.022).

Conclusion

In this study, common pathogens causing pleural infection were comparable to previous studies, and consisted of streptococci, staphylococci, and anaerobes. CURB-65 ≥2, structural lung disease, PSI risk class IV-V, no use of intrapleural fibrinolytics, hospital-acquired infection, older age, and SOFA score ≥ 2 are potential predictors of mortality in pleural infection.

Organizing empyema induced in mice by Streptococcus pneumoniae: effects of plasminogen activator inhibitor-1 deficiency

Background

Pleural infection affects about 65,000 patients annually in the US and UK. In this and other forms of pleural injury, mesothelial cells (PMCs) undergo a process called mesothelial (Meso) mesenchymal transition (MT), by which PMCs acquire a profibrogenic phenotype with increased expression of α-smooth muscle actin (α-SMA) and matrix proteins. MesoMT thereby contributes to pleural organization with fibrosis and lung restriction. Current murine empyema models are characterized by early mortality, limiting analysis of the pathogenesis of pleural organization and mechanisms that promote MesoMT after infection.

Methods

A new murine empyema model was generated in C57BL/6 J mice by intrapleural delivery of Streptococcus pneumoniae (D39, 3 × 10⁷–5 × 10⁹ cfu) to enable use of genetically manipulated animals. CT-scanning and pulmonary function tests were used to characterize the physiologic consequences of organizing empyema. Histology, immunohistochemistry, and immunofluorescence were used to assess pleural injury. ELISA, cytokine array and western analyses were used to assess pleural fluid mediators and markers of MesoMT in primary PMCs.

Results

Induction of empyema was done through intranasal or intrapleural delivery of S. pneumoniae. Intranasal delivery impaired lung compliance (p < 0.05) and reduced lung volume (p < 0.05) by 7 days, but failed to reliably induce empyema and was characterized by unacceptable mortality. Intrapleural delivery of S. pneumoniae induced empyema by 24 h with lung restriction and development of pleural fibrosis which persisted for up to 14 days. Markers of MesoMT were increased in the visceral pleura of S. pneumoniae infected mice. KC, IL-17A, MIP-1β, MCP-1, PGE₂ and plasmin activity were increased in pleural lavage of infected mice at 7 days. PAI-1^−/− mice died within 4 days, had increased pleural inflammation and higher PGE₂ levels than WT mice. PGE₂ was induced in primary PMCs by uPA and plasmin and induced markers of MesoMT.

Conclusion

To our knowledge, this is the first murine model of subacute, organizing empyema. The model can be used to identify factors that, like PAI-1 deficiency, alter outcomes and dissect their contribution to pleural organization, rind formation and lung restriction.

Pleural effusion adenosine deaminase: a candidate biomarker to discriminate between Gram-negative and Gram-positive bacterial infections of the pleural space

OBJECTIVES

Delay in the treatment of pleural infection may contribute to its high mortality. In this retrospective study, we aimed to evaluate the diagnostic accuracy of pleural adenosine deaminase in discrimination between Gram-negative and Gram-positive bacterial infections of the pleural space prior to selecting antibiotics.

METHODS

A total of 76 patients were enrolled and grouped into subgroups according to Gram staining: 1) patients with Gram-negative bacterial infections, aged 53.2±18.6 years old, of whom 44.7% had empyemas and 2) patients with Gram-positive bacterial infections, aged 53.5±21.5 years old, of whom 63.1% had empyemas. The pleural effusion was sampled by thoracocentesis and then sent for adenosine deaminase testing, biochemical testing and microbiological culture. The Mann-Whitney U test was used to examine the differences in adenosine deaminase levels between the groups. Correlations between adenosine deaminase and specified variables were also quantified using Spearman's correlation coefficient. Moreover, receiver operator characteristic analysis was performed to evaluate the diagnostic accuracy of pleural effusion adenosine deaminase.

RESULTS

Mean pleural adenosine deaminase levels differed significantly between Gram-negative and Gram-positive bacterial infections of the pleural space (191.8±32.1 U/L vs 81.0±16.9 U/L, p<0.01). The area under the receiver operator characteristic curve was 0.689 (95% confidence interval: 0.570, 0.792, p<0.01) at the cutoff value of 86 U/L. Additionally, pleural adenosine deaminase had a sensitivity of 63.2% (46.0-78.2%); a specificity of 73.7% (56.9-86.6%); positive and negative likelihood ratios of 2.18 and 0.50, respectively; and positive and negative predictive values of 70.6% and 66.7%, respectively.

CONCLUSIONS

Pleural effusion adenosine deaminase is a helpful alternative biomarker for early and quick discrimination of Gram-negative from Gram-positive bacterial infections of the pleural space, which is useful for the selection of antibiotics.

Cancer Risk in Patients With Empyema: A Nationwide Population-Based Study

This study aimed to evaluate cancer risk and possible risk factors in patients diagnosed with empyema. A total of 31,636 patients with newly diagnosed empyema between January 1, 1999 and December 31, 2010 were included in this study. Standardized incidence ratios (SIRs) were calculated to compare the cancer incidence in these empyema patients to that in the general population. Adjusted hazard ratios were also calculated to investigate whether characteristics increased cancer risk. During the 12-year study period, 2,654 cancers occurred in 31,636 patients with empyema, yielding an SIR of 2.67 (95% confidence interval [CI] 2.57-2.78). We excluded cancer that occurred within 1 year to avoid surveillance bias. The cancer risk remained significantly increased (SIR 1.50, 95% CI 1.41-1.58). Specifically, patients with empyema had higher SIR of cancers of the head and neck (1.50, 95% CI 1.41-1.58), esophagus (2.56, 95% CI 1.92-3.33), stomach (1.49, 95% CI 1.16-1.89), liver and biliary tract (2.18, 95% CI 1.93-2.45), and lung and mediastinum (1.62, 95% CI 1.39-1.86). Age ≥ 60, male sex, diabetes mellitus, and liver cirrhosis were independent risk factors for cancer development. Our study demonstrates an increased incidence of cancer development in patients with empyema, and patients' age ≥ 60, men, and those with diabetes mellitus and liver cirrhosis showed a higher incidence of developing cancer compared to the general population. The association between such kind of infection and secondary malignancy may be elucidated by further study.

Clinical characteristics of 323 children with parapneumonic pleural effusion and pleural empyema due to community acquired pneumonia

BACKGROUND

An increasing incidence of parapneumonic effusion and pleural empyema (PPE/PE) in children has been found in several studies published in the last decades. The aim of the study was to evaluate the incidence, etiology, clinical features, treatment strategies and outcomes of PPE/PE in children treated in a referral pulmonary center in central Poland.

MATERIAL AND METHODS

We performed a retrospective analysis of clinical, radiological and laboratory data of all children aged between 1 month and 18 years with PPE/PE due to community acquired pneumonia (CAP) between January 2002 and December 2013.

RESULTS

One thousand nine hundred and thirty three children with CAP were hospitalized between 2002 and 2013. Parapneumonic effusion or PE was diagnosed in 323 children (16.7%). The proportion of children with CAP related PPE/PE increased from 5.4% in 2002 to 18.8% in 2013. Streptococcus pneumoniae was the most common causative microorganism, responsible for 66.7% cases of known etiology. All children were treated with antibiotics and in 22.6%, and 74.3% of the patients therapeutic thoracentesis, pleural drainage with or without intrapleural fibrinolysis was performed, respectively. Approximately 3% of patients required surgical intervention.

CONCLUSIONS

A significant increase in the incidence of PPE/PE in children with CAP treated in our institution in the last twelve years was found. S. pneumoniae was the most common causative microorganism. Antibiotic therapy with chest drain insertion ± intrapleural fibrinolysis is an effective treatment of PPE/PE and surgical intervention is seldom necessary. With proper management, the overall prognosis in children with CAP related PPE/PE is good.

Invasive pneumococcal disease: Clinical outcomes and patient characteristics 2-6 years after introduction of 7-valent pneumococcal conjugate vaccine compared to the pre-vaccine period, the Netherlands

BACKGROUND

Implementation of 7-valent pneumococcal conjugate vaccine (PCV7) in the Dutch national immunization program for infants led to a shift from vaccine to non-vaccine serotypes in invasive pneumococcal disease (IPD) in all age groups. We studied the impact of the serotype shift on clinical syndromes and outcomes.

METHODS

Pneumococcal isolates from hospitalized IPD patients obtained from nine sentinel microbiology laboratories, covering 25% of the Dutch population, were serotyped. Clinical syndromes, outcomes and patient characteristics in the post-PCV7 (2008-2012) period were compared with the pre-PCV7 period (2004-2006). Serotype specific propensity of the association with empyema, meningitis and death was calculated.

RESULTS

Invasive pneumonia incidence significantly decreased in children <5 years and elderly ≥65 years, but increased in 5-64 years old from 4.92 to 5.58 cases/100.000/year (RR 1.13 95% CI 0.99-1.29). Empyema incidence significantly increased in elderly 65 years and older from 0.61 to 2.60 cases/100.000/year (RR 4.28 95% CI 1.97-9.33), mainly due to serotype 1. The incidence of meningitis only declined significantly in children <5 years. IPD case-fatality decreased in children <5 years from 5% to 3%, in 5-64 years old from 9% to 7% and in elderly ≥65 years significantly from 22% to 17%, due to lower case-fatality rates for most emerging non-PCV7 serotypes.

CONCLUSIONS

An increase in empyema incidence was observed in persons ≥65 years old in the post-PCV7 era, mainly due to the emergence of serotype 1, although overall IPD case-fatality decreased. Extended conjugate vaccines that target serotype 1 or serotypes with high case-fatality may offer further reduction of pneumococcal disease burden.

Nasopharyngeal carriage of Streptococcus pneumoniae and other bacteria in the 7th year after implementation of the pneumococcal conjugate vaccine in the Netherlands

After introduction of the 7-valent pneumococcal conjugate vaccine (PCV7) in the infant national immunization program (NIP) in the Netherlands in 2006, Streptococcus pneumoniae strains of the non-vaccine serotype 19A emerged and became the dominant serotype in carriage in children and their parents. Similar patterns were observed in other European countries and the United States. Increases in carriage rates of Staphylococcus aureus and non-typeable (NT) Haemophilus influenzae were also observed. After switching of PCV7 to 10-valent vaccine (PCV10) in 2011, a new carriage surveillance study was performed in the winter of 2012/2013. Nasopharyngeal carriage of S. pneumoniae, H. influenzae, S. aureus, and Moraxella catarrhalis was determined by conventional culture in 330 PCV10-vaccinated 11-month-old children, 330 PCV7-vaccinated 24-month-old children, and their parents. Carriage prevalence was compared with similar carriage studies conducted in 2005, 2009, and 2010/2011. Although serotype 19A remained the most frequently carried pneumococcal serotype in children, prevalence of 19A significantly declined in PCV7-vaccinated 24-month-old children (14% to 8%, p=0.01), but less in PCV10-vaccinated 11-month-old children (12% to 9%, p=0.31). Carriage of H. influenzae remained stable at an elevated level (65% in 11-month-olds and 69% in 24-month-olds), while the carriage of S. aureus returned to pre-PCV7 levels in 11-month-old children (14% in 2010/2011 to 7% in 2012/2013), but not in 24-month-olds (remained at 7%). Our results might indicate a new balance between replacing non-vaccine pneumococcal serotypes and other potential pathogenic bacteria in nasopharyngeal carriage. Carriage studies are valuable tools in assessing vaccine effects on pathogens circulating in the population, for evaluation of PCV impact, and in predicting changes in respiratory and invasive disease.

Pleural Empyema and Aortic Aneurysm: A Retrospective National Population-Based Cohort Study

Pleural empyema (PE) may evolve into necrosis, fistula in the thorax, and sepsis; thus, it is also associated with high mortality.We investigated and analyzed the risk of aortic aneurysm (AA) in a cohort study of patients with PE.A total of 34,250 patients diagnosed with PE were identified as the PE cohort, and 137,000 patients without PE were selected randomly as the control group and matched by sex, age, and index year of PE diagnosis. Patients ages 20 years and younger with a history of AA were excluded. The risk of AA was analyzed using a Cox proportional hazards regression model.Excess risk of AA development was 1.69-fold higher in PE patients (adjusted hazard ratio [aHR] = 1.69; 95% confidence interval [CI] = 1.39-2.05) compared with non-PE patients. The patients with PE exhibited a greater adjusted risk of AA (aHR = 2.01; CI = 1.44-2.81) even if they did not have any of the 9 comorbidities included in our analysis (diabetes, hypertension, hyperlipidemia, chronic obstructive pulmonary disease, heart failure, cardiac artery disease, stroke, bacterial endocarditis, and rheumatic endocarditis). Compared with the patients without any of the 9 comorbidities or PE, the patients with only PE had a greater risk of developing AA (aHR = 2.00; CI = 1.43-2.79). The PE cohort had a significantly higher cumulative incidence of AA than the non-PE cohort did during 12 years of follow-up.In a large-scale cohort, patients with PE are linked with an increased risk of AA.

Humoral immune responses to Streptococcus pneumoniae in the setting of HIV-1 infection

Streptococcus pneumoniae (pneumococcus) remains one of the most commonly identified causes of bacterial infection in the general population, and the risk is 30-100 fold higher in HIV-infected individuals. Both innate and adaptive host immune responses to pneumococcal infection are important against pathogen invasion. Pneumococcal-specific IgA antibody (Ab) is key to control infection at the mucosal sites. Ab responses against pneumococcal infection by B cells can be generated through T cell-dependent or T cell-independent pathways. Depletion of CD4+ T cells is a hallmark of immunodeficiency in HIV infection and this defect also contributes to B cell dysfunction, which predisposes to infections such as the pneumococcus. Two pneumococcal vaccines have been demonstrated to have potential benefits for HIV-infected patients. One is a T cell dependent 13-valent pneumococcal conjugate vaccine (PCV13); the other is a T cell independent 23-valent pneumococcal polysaccharide vaccine (PPV23). However, many questions remain unknown regarding these two vaccines in the clinical setting in HIV disease. Here we review the latest research regarding B cell immune responses against pneumococcal antigens, whether derived from potentially invading pathogens or vaccinations, in the setting of HIV-1 infection.

Detection of bacteria and viruses in the pleural effusion of children and adults with community-acquired pneumonia

ABSTRACT 

Aim: To study the etiology and the utility of new molecular methods in the diagnosis of complicated pneumonia with empyema. Materials & methods: Bacteria and viruses detection was performed by several traditional and molecular methods in the pleural fluid (PF) of 60 patients (38 children) with community-acquired pneumonia (CAP). Results: Despite prior antimicrobial therapy in 49 (81.7%) CAP patients, an etiological diagnosis could be established in 41 (68.3%), 35 being (58.3%) Streptococcus pneumoniae. PF culture was positive in only 6 patients but each molecular test detected more than 82% of cases. Conclusion: Traditional culture methods have poor diagnostic sensitivity in PF because most CAP patients are under antimicrobial therapy when it is obtained. S. pneumoniae detection by molecular methods highly improves diagnosis.

Sinusitis and pneumonia hospitalization after introduction of pneumococcal conjugate vaccine

BACKGROUND AND OBJECTIVE

Streptococcus pneumoniae is a major cause of pneumonia and sinusitis. Pneumonia kills >1 million children annually, and sinusitis is a potentially serious pediatric disease that increases the risk of orbital and intracranial complications. Although pneumococcal conjugate vaccine (PCV) is effective against invasive pneumococcal disease, its effectiveness against pneumonia is less consistent, and its effect on sinusitis is not known. We compared hospitalization rates due to sinusitis, pneumonia, and empyema before and after sequential introduction of PCV7 and PCV13.

METHOD

All children 0 to <18 years old hospitalized for sinusitis, pneumonia, or empyema in Stockholm County, Sweden, from 2003 to 2012 were included in a population-based study of hospital registry data on hospitalizations due to sinusitis, pneumonia, or empyema. Trend analysis, incidence rates, and rate ratios (RRs) were calculated comparing July 2003 to June 2007 with July 2008 to June 2012, excluding the year of PCV7 introduction.

RESULTS

Hospitalizations for sinusitis decreased significantly in children aged 0 to <2 years, from 70 to 24 cases per 100 000 population (RR = 0.34, P < .001). Hospitalizations for pneumonia decreased significantly in children aged 0 to <2 years, from 450 to 366 per 100 000 population (RR = 0.81, P < .001) and in those aged 2 to <5 years from 250 to 212 per 100 000 population (RR = 0.85, P = .002). Hospitalization for empyema increased nonsignificantly. Trend analyses showed increasing hospitalization for pneumonia in children 0 to <2 years before intervention and confirmed a decrease in hospitalizations for sinusitis and pneumonia in children aged 0 to <5 years after intervention.

CONCLUSIONS

PCV7 and PCV13 vaccination led to a 66% lower risk of hospitalization for sinusitis and 19% lower risk of hospitalization for pneumonia in children aged 0 to <2 years, in a comparison of 4 years before and 4 years after vaccine introduction.

Pleural infection and empyema

Increasing incidence of pleural infection has been reported worldwide in recent decades. The pathogens responsible for pleural infection are changing and differ from those in community acquired pneumonia. The main treatments for pleural infection are antibiotics and drainage of infected pleural fluid. The efficacy of intrapleural fibrinolytics remains unclear, although a recent randomized control study showed that the novel combination of tissue plasminogen activator and deoxyribonuclease had improved clinical outcomes. Surgical drainage is a critical treatment in patient with progression of sepsis and failure in tube drainage.

Pneumococcal vaccines and the prevention of community-acquired pneumonia

Community-acquired pneumonia (CAP) is a disease that frequently affects children and adults throughout the world. As it places a considerable burden on society and, particularly, healthcare resources, any means of reducing its incidence and impact arouses great interest. A substantial number of paediatric and adult CAP cases are due to Streptococcus pneumoniae but, fortunately, there are effective vaccines available that are likely to have a significant impact on CAP-related medical, social and economic problems. The main aim of this paper is to evaluate the published evidence concerning the impact of pneumococcal vaccines on CAP in children and adults. The original 7-valent pneumococcal conjugate vaccine (PCV-7) completely modified the total burden of pneumococcal diseases in vaccinated children and unvaccinated contacts of any age. However, the existence of some problems moderately reducing its preventive efficacy has led to the development of PCVs with a larger number of pneumococcal serotypes, including those that were previously of marginal importance but now cause of severe disease. It is reasonable to think that these PCVs (particularly PCV13, which includes all of the most important serotypes emerging since the introduction of PCV7) will further reduce the importance of pneumococcal diseases, although it is still not clear whether the replacement of the 23-valent polysaccharide vaccine with PCV13 would be more protective in adults.

Diagnosis of pneumococcal pneumonia: current pitfalls and the way forward

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia. However, it can also asymptomatically colonize the upper respiratory tract. Because of the need to distinguish between S. pneumoniae that is simply colonizing the upper respiratory tract and S. pneumoniae that is causing pneumonia, accurate diagnosis of pneumococcal pneumonia is a challenging issue that still needs to be solved. Sputum Gram stains and culture are the first diagnostic step for identifying pneumococcal pneumonia and provide information on antibiotic susceptibility. However, these conventional methods are relatively slow and insensitive and show limited specificity. In the past decade, new diagnostic tools have been developed, particularly antigen (teichoic acid and capsular polysaccharides) and nucleic acid (ply, lytA, and Spn9802) detection assays. Use of the pneumococcal antigen detection methods along with biomarkers (C-reactive protein and procalcitonin) may enhance the specificity of diagnosis for pneumococcal pneumonia. This article provides an overview of current methods of diagnosing pneumococcal pneumonia and discusses new and future test methods that may provide the way forward for improving its diagnosis.

Chronic empyema: importance of preventing complications in the management of pleural effusions

We report a case of chronic empyema in a 63-year-old man with a history of asbestos exposure and alcohol overconsumption. In 2009, he presented with dyspnoea, exudative pleurisy on the right side with no symptoms of infection or malignancy. In 2013, the patient presented with increased dyspnoea and a massive chronic empyema had evolved. Culture of the pleural fluid was positive for Escherichia coli and anaerobic bacteria, and he was treated with antibiotics, chest drainage as well as surgical evacuation. After surgery, as the lung failed to expand, growth of opportunistic bacteria and rising C reactive protein obliged long-time treatment with broad-spectrum antibiotics as well as chest drainage with daily saline flushes. The patient still suffers from fatigue, poor nutritional status and anaemia, and further treatment with chest drainage and antibiotics is planned. Advanced chronic empyema is a difficult condition with poor response to treatment, and diagnostic delay is the main cause of complications.