Parapneumonic Effusion in Children: An Up-to-Date Review

A multicenter study on the epidemiology of complicated parapneumonic effusion in the era of currently available pneumococcal conjugate vaccines

BACKGROUND

Parapneumonic effusion (PPE) is a common complication of pneumonia. Streptococcus pneumoniae is the most common cause of bacterial pneumonia. A reduction in pneumonia hospitalizations has been observed since the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7). Despite this apparent benefit, an increase in the incidence of PPE was recorded in some countries following PCV7 implementation. As the 13-valent pneumococcal conjugate vaccine (PCV13) was expected to provide a wider protection against PPE, the aim of the present study was to evaluate the impact of PCV13 introduction on the epidemiology of complicated parapneumonic effusion (c-PPE) among children in the Athens greater area.

METHODS

All cases of community-acquired pneumonia (CAP) with PPE requiring chest tube insertion (complicated PPE, c-PPE) hospitalized in the 3 public Children's hospitals in Athens between 01/01/2004 and 31/12/2019 were included in the study.

RESULTS

A total of 426 cases of c-PPE associated with pneumonia were recorded of which 198 were admitted during 2004-2010 (period A, prePCV13/PCV -7 introduction period) and 228 during 2011-2018 (period B, post - PCV13 period). A definite bacterial etiology was established in 44.4 % of all cases and of those 25.4 % were caused by S. pneumoniae. An increasing trend in c-PPE incidence was observed during period A; although, a significant decrease on c-PPE annual rates was observed during the period B (p = 0.011), a remarkable increase in serotype 3 cases was recorded.

CONCLUSION

A decreasing time trend in c-PPE cases among children was shown after the introduction of PCV13 in our area. However, serotype 3 is nowadays a common cause of PPE. Hence, continuous surveillance is imperative in order to follow c-PPE epidemiology over time.

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

BACKGROUND

In children with parapneumonic effusion (PPE), it remains unclear when conservative treatment with antibiotics suffixes or when pleural drainage is needed. In this study we evaluate clinical features and outcomes of children with PPE.

METHODS

A retrospective, multicentre cohort study at 4 Dutch pediatric departments was performed, including patients 1-18 years treated for PPE between January 2010 and June 2020.

RESULTS

One hundred thirty-six patients were included (mean age 8.3 years, SD 4.8). 117 patients (86%) were treated conservatively and 19 (14%) underwent pleural drainage. Patients undergoing pleural drainage had mediastinal shift more frequently compared with conservatively treated patients (58 vs. 3%, difference 55%; 95% CI: 32%-77%). The same accounted for pleural septations/pockets (58 vs. 11%, difference 47%; 95% CI: 24%-70%), pleural thickening (47 vs. 4%, difference 43%; 95% CI: 20%-66%) and effusion size (median 5.9 vs. 2.7 cm; P = 0.032). Conservative management was successful in 27% of patients (4 of 15) with mediastinal shift, 54% of patients (13 of 24) with septations/pockets, 36% of patients (5 of 14) with pleural thickening, and 9% of patients (3 of 32) with effusions >3 cm, all radiological signs generally warranting pleural drainage. In patients treated conservatively, median duration of hospitalization was 5 days (IQR 4-112) compared with 19 days (IQR 15-24) in the drainage group ( P < 0.001), without significant difference in readmission rate (11 vs. 4%, difference 6%; 95% CI: -8%-21%).

CONCLUSION

This study suggests that the greater amount of children with PPE could be treated conservatively with antibiotics only, especially in absence of mediastinal shift, pleural septations/pockets, pleural thickening or extensive effusions.

Inpatient outcomes for children receiving empiric methicillin-resistant Staphylococcus aureus coverage for complicated pneumonia

Rigorous evidence for antibiotic management of pediatric complicated pneumonia is lacking, likely contributing to variation in empiric antibiotic(s). Using the Pediatric Health Information System database, we sought to describe use and clinical outcomes of children hospitalized with complicated pneumonia who received empiric antibiotic regimens with and without methicillin-resistant Staphylococcus aureus (MRSA) coverage. We evaluated empiric antibiotic selection on Day 0-1, grouping based on use of an antibiotic with or without MRSA coverage. We used generalized linear mixed effects models to examine the association of MRSA coverage and outcomes. Across 46 children's hospitals, 71.5% of children (N = 1279) received an empiric antibiotic regimen with MRSA coverage. In adjusted analyses, length of stay, need for repeat pleural drainage procedures, 7-day emergency department revisits and 7-day readmissions were similar between groups. Future prospective studies examining the need for MRSA coverage may assist in refining national treatment guidelines for complicated pneumonia in children.

Levels of lactic acid's concordance with pH in pediatric parapneumonic pleural effusion

Purpose of the article: The indication of pleural drainage in parapneumonic pleural effusion (PPE) is still controversial. Pleural fluid's (PF) pH is widely used as an indicator of the need for pleural drainage. We hypothesized that PF's lactate will have a high concordance with pH, and thus, may be a valuable tool to determine the need for pleural drainage in pediatric PPE.

MATERIALS AND METHODS

We performed a descriptive, prospective study sequentially enrolling those pediatric patients admitted to a tertiary University Hospital with a PPE between 2008 and 2018. Patients were classified in two groups: drainable PPE (pH < 7) and non-drainable PPE (pH > 7). Correlation with the pH, the area under the curve (AUC), and the sensitivity and specificity values for lactate and other parameters (glucose, and LDH) were analysed too.

RESULTS

72 patients with a median age of 4 years (interquartile range 2.25-6) were included. Both groups were homogeneous. Lactate levels were higher in the drainable PPE group (p < 0.001), and a strong inverse correlation between pH and lactate was found (r: -0.7; p < 0.001). A lactate cut-off value of 60.5 mmol/L, exhibit an AUC of 0.86 with a sensitivity of 70% and a high specificity (97.9%) to predict a pH < 7.

CONCLUSIONS

Our data indicates that lactate in PF presents a strong correlation with pH and could potentially serve as a highly specific biomarker of the need for pleural drainage.

Loculated empyema in a neonate successfully treated with chest tube thoracostomy and antibiotics

Empyema thoracis, defined as the accumulation of pus in the pleural space, is a rare entity in the neonatal period. There are very few cases described in the medical literature and there are still no treatment protocols in the management of empyema in neonates. In older infants and children, intrapleural fibrinolytics and surgery are often utilized since treatment of complicated parapneumonic effusions with chest tube and antibiotics alone often fail due to the viscous fluid and presence of loculations. Presented here is a case of a term neonate who exhibited symptoms of respiratory distress on the sixth day of life. Imaging modalities revealed massive left sided pleural effusion with loculations and mass effects. Pleural fluid was grossly pus and exudative in nature. Gram stain revealed gram-positive cocci but culture was negative. Empiric broad-spectrum antibiotics and chest tube drainage were utilized and patient was discharged after forty-seven days of hospital admission. In spite of prolonged hospital stay, patient survived with no complications. Therefore, nonoperative therapy could still be an option for neonates with loculated empyema. The key to success in treatment is immediate identification of effusion, prompt initiation of antibiotics, and early effective chest tube drainage.

Identifying pneumococci in parapneumonic pleural effusion: Is there a role for culture-independent methods?

OBJECTIVE

To evaluate culture-independent procedures (immunochromatography and quantitative polymerase chain reaction [qPCR]) in the detection and susceptibility of Streptococcus pneumoniae directly from culture-negative pleural fluid (PF) in children.

METHOD

Detection of S. pneumoniae in PF of children with parapneumonic effusion and/or empyema by using two culture-independent methods: an immunochromatographic membrane test (IMT) which identifies the pneumococcal C antigen, and a real-time PCR test to detect pneumococcal genes lytA and pbp2b, a marker of susceptibility of β-lactam agents, in PF samples.

RESULTS

We tested 36 PF specimens and recorded the previous use of antimicrobials. In the final analysis, 34 samples were included. IMT and qPCR presented positive results in 23 (67.6%) and 24 (70.6%) of the samples, respectively, showing a moderate agreement (k = 0.518) between the two methods. From the 36 children included, 34 (94.4%) had antibiotic data available by the time when PFs were collected. Thirty-four (100%) children had been given treatment before PF sampling, with 33 (97%) receiving β-lactam antibiotics administered empirically. Of the 24 lytA real-time positive samples, 21 (87.5%) were also positive for pbp2b, a marker of β-lactam susceptibility.

CONCLUSION

The reduced sensitivity of culture for pneumococcal detection can be improved through the addition of IMT and qPCR analysis. The utility of qPCR combining detection of lytA and a marker of β-lactam susceptibility should be explored further.

Pleural Thickening after Pleural Effusion: How can we Follow-Up in Children?

INTRODUCTION

No clear information exists about the factors affecting pleural thickening following parapneumonic effusion in children. We aimed to investigate factors that affect the resolving time of pleural thickening after parapneumonic effusion.

METHODS

Between the years of 2007-18, 91 patients, which were followed due to diagnosis of pleural thickening after parapneumonic effusion, were assessed. Ages, complaints, physical examination findings, laboratory results, chest x-ray and ultrasonography findings, treatments, duration of treatment and recovery time of the patients were examined terms in of pleural thickening resolving time.

RESULTS

The mean age of patients was 7.5 ± 5.0 years. Pleural thickening resolving time was 151 ± 6.8 days. The resolving time for pleural thickening was delayed with older ages, longer duration of complaints, fever before hospital admission and treatment, lower oxygen saturation at the time of admission, crackles in the physical examination, higher white blood cell count and pleural fluid density (p = 0.018, p = 0.001, p = 0.021, p = 0.020, p = 0.024, p = 0.025, p = 0.021, p = 0.019). In addition, the amount of effusion measured by thorax ultrasonography, fibrinolytic usage, and complications had a role in the delayed resolving time (p = 0.034, p = 0.001, p = 0.034). Pleural thickening resolved in 80% of the patients.

CONCLUSION

In this report, 80% of pleural thickening, following parapneumonic effusion resolved within 5 months. Patients who do not have a complication during follow-up are not required to monitor with frequent chest x-ray. Patients with a higher amount of pleural effusion, complications and need for fibrinolytic treatment should be followed more carefully.

Empyema Thoracis in Children: A 5-Year Experience in a Tertiary Care Institute

Objective:

Empyema thoracis (ET) in children is a disease of significant morbidity and mortality. In the event of failure to resolute following intercostal chest tube drainage (ICD), thoracotomy decortication (TDC) remains the treatment of choice. We have reviewed the outcome of management of 96 cases of ET with the intent to establish the scope of ICD as primary form of the management.

Materials and Methods:

This is a retrospective study of 96 patients of ET who were managed in pediatric surgery department over a period of 5 years (April 2013 – March 2018). Ninety-six patients at a single center met inclusion criteria for having ET and underwent ICD. We excluded the cases where video-assisted thoracoscopic surgery was provided as primary treatment. The patients were categorized into complicated and uncomplicated groups. Those with pyopneumothorax, encysted empyema, multiloculated empyema, and bilateral ET were assigned as complicated group. There were two treatment groups: (I) those responded with ICD alone (II) those with ICD followed by TDC.

Results:

All 96 cases received ICD as primary management. There were 54 uncomplicated cases and 42 complicated cases. Out of 42 complicated cases, 26 patients recovered with ICD alone and 16 patients needed TDC. A total of 80 (83.33%) patients (54 uncomplicated ± 26 complicated) recovered with ICD alone. Significant complications were encountered in follow-up of patients who underwent delayed thoracotomy in the form of overriding of the ribs (n = 3) and postoperative air leak (n = 4). There was no mortality in our series.

Conclusion:

Early initiation of management of ET with intercostal tube drainage is simple, safe, effective even in complicated cases, and has less complications. Thoracotomy with decortication should be reserved for ICD failure cases.

Metabolomics Reveals Anaerobic Bacterial Fermentation and Hypoxanthine Accumulation for Fibrinous Pleural Effusions in Children with Pneumonia

Fibrin formation in infectious parapneumonic effusion (IPE) characterizes complicated parapneumonic effusion and is important for providing guidelines for the management of IPEs that require aggressive interventions. We aim to identify metabolic mechanisms associated with bacterial invasion, inflammatory cytokines, and biochemical markers in cases of fibrinous infectious pleural effusions in children with pneumonia. Pleural fluid metabolites were determined by ¹H nuclear magnetic resonance spectroscopy. Metabolites that contributed to the separation between fibrinous and nonfibrinous IPEs were identified using supervised partial least squares discriminant analysis ( Q²/ R² = 0.84; P_permutation < 0.01). IL-1β in the inflammatory cytokines and glucose in the biochemical markers were significantly correlated with 11 and 9 pleural fluid metabolites, respectively, and exhibited significant overlaps. Four metabolites, including glucose, lactic acid, 3-hydroxybutyric acid, and hypoxanthine, were significantly correlated with plasminogen activator inhibitor type 1 in the fibrinolytic system enzymes. Metabolic pathway analysis revealed that anaerobic bacterial fermentation with increased lactic acid and butyric acid via glucose consumption and adenosine triphosphate hydrolysis with increased hypoxanthine appeared to be associated with fibrinous IPE. Our results demonstrate that an increase in lactic acid anaerobic fermentation and hypoxanthine accumulation under hypoxic conditions are associated with fibrin formation in IPE, representing advanced pleural inflammatory progress in children with pneumonia.

Establishing Equipoise: National Survey of the Treatment of Pediatric Para-Pneumonic Effusion and Empyema

BACKGROUND

Despite six randomized trials of various treatments for pediatric para-pneumonic effusion (PPE), management approaches differ. The purpose of this study was to gain insight into opinions on PPE treatment with the goal of designing a definitive trial to generate consensus intervention guidelines.

METHODS

To evaluate physician opinions regarding PPE management, we developed a survey based on input from a nationwide, multi-disciplinary advisory group that established content validity. The survey was disseminated broadly to six pediatric medicine and interventional radiology groups. Descriptive and χ² statistics were calculated.

RESULTS

There were 741 respondents (response rate 13.1%), of whom 52.2% were surgeons, 15.2% hospitalists, 14.2% pulmonologists, 12.4% intensivists, and 6.0% interventional radiologists. Nearly all respondents (97.3%) reported caring primarily for pediatric patients. Eighty percent reported no written institutional treatment guidelines. Nearly all (90.3%) agreed that patients require antibiotics, but there was disagreement regarding their duration. Respondents also were split as to how often PPE required drainage. There were multiple absolute indications for drainage, including mediastinal shift on chest radiograph (67.2%) and loculations on imaging (47.7%). There were substantial differences in the preferred first-line methods of drainage based on the treating physician's specialty, with surgeons preferring tube thoracostomy and a fibrinolytic agent (42.0%) or video-assisted thoracoscopic surgery (41.6%), whereas interventional radiologists preferred either a tube thoracostomy (46.4%) or a tube thoracostomy with a fibrinolytic agent (39.3%) (p < 0.001). A large majority (75.3%) believed that the published evidence does not identify the optimal intervention.

CONCLUSIONS

There is a lack of consensus regarding the optimal treatment of PPE. Respondents believed the published evidence is inconclusive and were willing to participate in a prospective trial. These findings will help inform the design of a randomized, pragmatic clinical trial to optimize PPE management.