Incidence and etiologies of complicated parapneumonic effusions in children, 1996 to 2001

Pleural Fluid Biomarkers of Pediatric Parapneumonic Effusion

Background/Objectives: Parapneumonic pleural effusion (PPE) secondary to community-acquired pneumonia is the most common cause of pediatric pleural effusion. This study aimed to evaluate the pleural fluid characteristics of pediatric patients with PPE and to compare biomarkers between infants (1-12 months) and children (1-14 years). Methods: Fifty-four pediatric patients (14 infants and 40 children) with PPE were included. Pleural fluid samples were analyzed for white blood cell (WBC) count, glucose, total protein, lactate dehydrogenase (LDH), adenosine deaminase (ADA), and pH levels. Differences between age groups and correlations between age and pleural fluid biomarkers were assessed. Results: Most pediatric PPE cases exhibited biochemical characteristics consistent with pleural exudate: WBC > 1000 cells/µL, total protein > 3 g/dL, LDH > 200 U/L. Infants showed a predominance of mononuclear WBC, while children exhibited a predominance of polymorphonuclear WBC. Glucose levels were higher, and total protein levels were lower in infants compared to children. Age was positively correlated with polymorphonuclear WBC percentage (rho = 0.509, p < 0.001) and protein levels (rho = 0.622, p < 0.001), whereas glucose levels were negatively correlated with age (rho = -0.274, p = 0.043). Conclusions: Age-specific differences in pleural fluid biomarkers were observed in pediatric patients with PPE, suggesting a more robust and acute inflammatory response in children compared to infants. These findings underscore the importance of considering age-related variations in the inflammatory response when diagnosing and managing PPE in pediatric populations.

Incidence trends of parapneumonic pleural effusions/empyema in children 2009 to 2018 from health insurance data: Only temporal reduction after the introduction of PCV13

BACKGROUND

Recently, emergence of a higher proportion of serotype 3 in children with parapneumonic pleural effusion/empyema (PPE/PE) were observed in Germany despite general immunization with 13-valent pneumococcal conjugate vaccine (PCV13) since 2009. The impact of PCV13 on the overall incidence of PPE/PE in children is unclear.

METHODS

Annual incidence of PPE/PE in children were determined using secondary health care data for 2009-2018, provided by the Barmer statutory health insurer, serving about 11% of the German population. Temporal trends of the annual incidence were modelled applying generalized additive models.

RESULTS

Overall incidence of PPE/PE in children ( ≤18 years) in the ten-year observation period was 18.17 per 100,000. The 0-1 year olds showed the highest incidence (43.09 per 100 000). PPE/PE incidence decreased from 2009 until 2013 (nadir 2013 was 15.36; 95% CI: 13.41-17.31). Since 2013, the data show an annual increase. The nadir of incidence for the 2-5 year olds (15.85; 95% CI: 11.27-20.43) and the 6-18 year olds (12.29; 95% CI: 10.23-14.36) was also in 2013, whereas for the 0-1 year olds it was found in 2014 (32.66; 95% CI: 23.79-41.54). The GAM across all age groups showed a nearly U-shaped curve between time and incidence of PPE/PE by calendar year (p-non-linear = 0.0017). The model confirms the nadir in the year 2013.

DISCUSSION

We found a nonlinear temporal trend of PPE/PE incidence in children with a decrease from 2009 to 2013 and a subsequent increase until 2018. The former might be explained by a quasi elimination of serotype 1, the latter by an increase in the proportion of serotype 3 as demonstrated in German surveillance data of pediatric PPE/PE cases generated during the same observation period.

[Guidelines for the Management of Community Acquired Pneumonia in Children and Adolescents (Pediatric Community Acquired Pneumonia, pCAP) - Issued under the Responsibility of the German Society for Pediatric Infectious Diseases (DGPI) and the German Society for Pediatric Pulmonology (GPP)]

The present guideline aims to improve the evidence-based management of children and adolescents with pediatric community-acquired pneumonia (pCAP). Despite a prevalence of approx. 300 cases per 100 000 children per year in Central Europe, mortality is very low. Prevention includes infection control measures and comprehensive immunization. The diagnosis can and should be established clinically by history, physical examination and pulse oximetry, with fever and tachypnea as cardinal features. Additional signs or symptoms such as severely compromised general condition, poor feeding, dehydration, altered consciousness or seizures discriminate subjects with severe pCAP from those with non-severe pCAP. Within an age-dependent spectrum of infectious agents, bacterial etiology cannot be reliably differentiated from viral or mixed infections by currently available biomarkers. Most children and adolescents with non-severe pCAP and oxygen saturation > 92 % can be managed as outpatients without laboratory/microbiology workup or imaging. Anti-infective agents are not generally indicated and can be safely withheld especially in children of young age, with wheeze or other indices suggesting a viral origin. For calculated antibiotic therapy, aminopenicillins are the preferred drug class with comparable efficacy of oral (amoxicillin) and intravenous administration (ampicillin). Follow-up evaluation after 48 - 72 hours is mandatory for the assessment of clinical course, treatment success and potential complications such as parapneumonic pleural effusion or empyema, which may necessitate alternative or add-on therapy.

Thoracoscopy in stage 3 empyema thoracis in children - A safe and feasible alternative to thoracotomy

BACKGROUND

Even though the role of thoracoscopy is well defined in Stage 2 empyema thoracis and is very popular, its role in the management of advanced empyema is still unclear. The technical difficulties and the potential complications are the principal reasons for the hesitancy in attempting video assisted thoracoscopic surgery (VATS) in advanced stages.

METHODS

We prospectively studied the safety, feasibility and effectiveness of VATS for decortication in Stage 3 empyema.

RESULTS

In the 61 cases that we attempted VATS over the last 7 years, we could complete the procedure in 45 patients (73.77%). Four children among them required re-do procedure later for persistent problems. Conversion to thoracotomy was needed in 16 patients (26.23%). The post-operative hospital stay of patients who underwent primary VATS decortication was significantly less when compared to patients requiring conversion (p < 0.0001).

CONCLUSION

Thoracoscopy is a safe, feasible and effective option even in advanced empyema thoracis and should be offered in centers with adequate expertise and set up.

LEVEL OF EVIDENCE

Level II.

Pleural Tap-Guided Antimicrobial Treatment for Pneumonia with Parapneumonic Effusion or Pleural Empyema in Children: A Single-Center Cohort Study

Parapneumonic effusion or pleural empyema (PPE/PE) is a frequent complication of community-acquired pneumonia (CAP) in children. Different management approaches exist for this condition. We evaluated a 14-day treatment with amoxicillin (AMX) with/without clavulanic acid (AMC) confirmed or modified by microbiological findings from pleural tap. Children ≤16 years of age with radiologically diagnosed PPE/PE and initial diagnostic pleural tap were included at University Children’s Hospital Zurich from 2001–2015. AMX/AMC was given for 14 days and rationalized according to microbiological pleural tap results. Clinical and radiological follow-up was scheduled until six months or full recovery. In 114 of 147 (78%) children with PPE/PE a pathogen was identified by culture, polymerase chain reaction (PCR), and/or antigen testing. Streptococcus pneumoniae was detected in 90 (79%), S. pyogenes in 13 (11%), and Staphylococcus aureus in seven cases (6%), all but two cultured pathogens (96%) were sensitive to AMX/AMC. One-hundred two of 147 (69%) patients received treatment with AMX/AMC for 14 days. They recovered more rapidly than patients with a different management (p = 0.026). Of 139 children with follow-up, 134 (96%) patients fully recovered. In conclusion, 14-day AMX/AMC treatment confirmed and rarely modified by microbiological findings from pleural tap resulted in full recovery in >95% of children with PPE/PE.

Detection of the major bacterial pathogens among children suffering from empyema in Ahvaz city, Iran

Introduction

Empyema is one of the important causes of pediatric hospital admissions.

Aim

In this study, we had investigated the frequency rates of S aureus, S pneumoniae, H influenzae, and P aeruginosa using PCR and bacterial culture among children suffering from empyema in Ahvaz city, Iran.

Methods

This was a descriptive study conducted on the patients hospitalized in ICUs of two teaching Hospitals of Ahvaz, Iran, between March and September 2018 on 105 pleural fluid (PF) samples of the children less than 16 years of age with the diagnosis of empyema thoracis. These specimens were inoculated on the bacterial culture media and identified using biochemical characteristics. Then, the existence of the four pathogens mentioned above was evaluated using PCR method.

Result

In this study, these bacteria agents were identified in 81 (77.14%) and 30 (28.57%) cases using the PCR assay and bacterial culture, respectively. Moreover, the PCR assay identified the infectious agents in 51 (68%) of PFs where the culture method failed. S pneumoniae (63 cases) was recognized as the most common pathogen, followed by P aeruginosa(19 cases), S aureus(15 cases), and H influenzae (9 cases) using the bacterial culture and PCR. Co‐infections were detected in 21 samples (20%) using PCR and one sample using the bacterial culture (P aeruginosa and S pneumoniae).

Conclusion

In this study, we found the higher frequencies of these microorganisms using PCR than culture. In addition, we showed that PCR was a sensitive and accurate method that unaffected by antibiotic therapy and could detect well co‐infections.

Streptococcus pneumoniae potently induces cell death in mesothelial cells

Pleural infection/empyema is common and its incidence continues to rise. Streptococcus pneumoniae is the commonest bacterial cause of empyema in children and among the commonest in adults. The mesothelium represents the first line of defense against invading microorganisms, but mesothelial cell responses to common empyema pathogens, including S. pneumoniae, have seldom been studied. We assessed mesothelial cell viability in vitro following exposure to common empyema pathogens. Clinical isolates of S. pneumoniae from 25 patients with invasive pneumococcal disease and three reference strains were tested. All potently induced death of cultured mesothelial cells (MeT-5A) in a dose- and time-dependent manner (>90% at 10⁷ CFU/mL after 24 hours). No significant mesothelial cell killing was observed when cells were co-cultured with Staphylococcus aureus, Streptococcus sanguinis and Streptococcus milleri group bacteria. S. pneumoniae induced mesothelial cell death via secretory product(s) as cytotoxicity could be: i) reproduced using conditioned media derived from S. pneumoniae and ii) in transwell studies when the bacteria and mesothelial cells were separated. No excess cell death was seen when heat-killed S. pneumoniae were used. Pneumolysin, a cytolytic S. pneumoniae toxin, induced cell death in a time- and dose-dependent manner. S. pneumoniae lacking the pneumolysin gene (D39 ΔPLY strain) failed to kill mesothelial cells compared to wild type (D39) controls, confirming the necessity of pneumolysin in D39-induced mesothelial cell death. However, pneumolysin gene mutation in other S. pneumoniae strains (TIGR4, ST3 and ST23F) only partly abolished their cytotoxic effects, suggesting different strains may induce cell death via different mechanisms.

Evolution of practice in the management of parapneumonic effusion and empyema in children

AIM

To assess the evolution in management of children with parapneumonic effusion and empyema in a tertiary referral centre.

METHOD

We conducted a retrospective case note review of paediatric patients with parapneumonic effusion, pleural effusion and pleural empyema between December 2006 and December 2015. Digital database searches were performed to identify demographic data, referring hospital, radiological and microbiological investigations. Length of stay and morbidity were analysed.

RESULTS

One hundred fifteen patients had 159 interventions over the study period. Fifty-four children were successfully treated with intercostal drainage (ICD) and urokinase fibrinolysis alone. There were 19 primary video assisted thoracoscopic surgeries (VATS) and 12 VATS after initial intercostal drains. Thirty-three children required a thoracotomy, a reduction of 26% from the previous era (p=0.009). The median length of stay was 9days (range 2-54).

CONCLUSION

Parapneumonic effusion can be successfully treated with intercostal drainage and intrapleural fibrinolytics, but a proportion requires further surgical intervention. In our hospital, increased utilisation of fibrinolysis and VATS occurred with a corresponding decrease in the need for thoracotomy. Patients needing thoracotomy all had severe disease on ultrasound, but ultrasound did not reliably predict failure of fibrinolytic therapy.

LEVEL OF EVIDENCE

III.

Incidence, aetiology and outcome of pleural empyema and parapneumonic effusion from 1998 to 2012 in a population of New Zealand children

AIM

To document rising incidence rates of childhood empyema and parapneumonic effusion (PPE) in South Auckland, New Zealand between 1998 and 2012; to compare epidemiology, pathogens and outcomes of children with empyema and PPE; and to ascertain whether primary care antibiotic prescribing, delayed presentation, or bacterial epidemiology might account for the rising incident rates.

METHODS

Children aged 0 to14 years hospitalised with pleural empyema or PPE were retrospectively identified. Empyema was defined by ultrasound and pleural tap criteria. PPE was defined as the presence of pleural fluid on chest xray not fulfilling empyema criteria. Epidemiology, clinical features, microbiology and outcomes of empyema and PPE were compared and incidence rates analysed.

RESULTS

Of 184 cases identified, 104 met the criteria for empyema. Empyema incidence increased from 1 per 100 000 children aged 0 to 14 years in 1998 to 10 per 100 000 in 2012, with a peak incidence of 13 per 100 000 in 2009. Staphylococcus aureus was most frequently detected (n=38), followed by Streptococcus pneumoniae (n=31). Cases of S. aureus empyema increased 4 fold over the 15 years. Dominant S. pneumoniae serotypes were 1 and 14. Thirty-five percent of empyema and 53% of PPE cases received pre-hospital antibiotics. Children who received pre-hospital antibiotics were more than 40% less likely to require surgical intervention than those not pre-treated.

CONCLUSIONS

Childhood empyema incidence has increased markedly in South Auckland. Paediatric S. aureus empyema is becoming increasingly common in South Auckland. Pre-hospital antibiotic prescribing may mitigate the need for surgical intervention in our population.

Rapid and Sensitive Identification of Bacterial Infection and Bacteria Gram Types in Pleural Fluid of Children

Real-time polymerase chain reaction (RT-PCR) techniques have been increasingly used to detect microbial DNA in clinic for the diagnosis of bacterial infection. This study aims to developing an RT-PCR method to detect bacteria in pleural fluid (PF). We performed a method to simultaneously detect and classify the clinically relevant bacterial pathogens in hydrothorax with Gram probe RT-PCR (GRT-PCR), which targets the conserved region of the 16S rRNA gene. Our results showed this method could specifically and correctly identify 14 clinically important bacterial strains in hydrothorax including 7 gram-positive and 7 gram-negative bacteria. And the sensitivity of this GRT-PCR method in serial dilution can reach 10 CFU/mL. In clinical trial, 180 PF samples from children who were clinically suspected to suffer from bacterial pneumonia and empyema were collected. These samples were detected by GRT-PCR, standard culture, and biochemical routine analysis. The positive rate of the GRT-PCR array was 17.78% (32/180), significantly higher than that of PF culture (11.67%; 21/180; P = .003). When PF culture was used as control, the sensitivity of GRT-PCR was 95.24% (95% confidence interval = 74.13-99.75), and the specificity was 92.45% (95% confidence interval = 86.89-95.86). Our study showed that GRT-PCR is a more effective method for rapid, sensitive, and specific diagnosis of bacterial infection in hydrothorax compared with other traditional methods.

A clinical review of the pathophysiology, diagnosis, and treatment of pyothorax in dogs and cats

OBJECTIVE

To review the current literature in reference to the pathophysiology, diagnosis, and treatment of pyothorax in dogs and cats.

ETIOLOGY

Pyothorax, also known as thoracic empyema, is characterized by the accumulation of septic purulent fluid within the pleural space. While the actual route of pleural infection often remains unknown, the oral cavity and upper respiratory tract appear to be the most common source of microorganisms causing pyothorax in dogs and cats. In human medicine, pyothorax is a common clinical entity associated with bacterial pneumonia and progressive parapneumonic effusion.

DIAGNOSIS

Thoracic imaging can be used to support a diagnosis of pleural effusion, but cytologic examination or bacterial culture of pleural fluid are necessary for a definitive diagnosis of pyothorax.

THERAPY

The approach to treatment for pyothorax varies greatly in both human and veterinary medicine and remains controversial. Treatment of pyothorax has classically been divided into medical or surgical therapy and may include administration of antimicrobials, intermittent or continuous thoracic drainage, thoracic lavage, intrapleural fibrinolytic therapy, video-assisted thoracic surgery, and traditional thoracostomy. Despite all of the available options, the optimal treatment to ensure successful short- and long-term outcome, including the avoidance of recurrence, remains unknown.

PROGNOSIS

The prognosis for canine and feline pyothorax is variable but can be good with appropriate treatment. A review of the current veterinary literature revealed an overall reported survival rate of 83% in dogs and 62% in cats. As the clinical presentation of pyothorax in small animals is often delayed and nonspecific, rapid diagnosis and treatment are required to ensure successful outcome.

Clinical outcome of parapneumonic empyema in children treated according to a standardized medical treatment

Treatment of parapneumonic empyema (PE) consists of intravenous antibiotics and, in case of large effusions and persisting fever, pleural chest drain (±intrapleural fibrinolytics) or video-assisted surgical intervention. We standardized the treatment for PE in our tertiary care center choosing a first-step nonsurgical approach. The aim was to evaluate the need for surgery and to collect data on disease course, outcome, and microbiology. For all children treated for PE between 2006 and 2013, data were prospectively collected concerning treatment, length of stay, duration of fever, complications, and causative agent. Of 132 children treated for PE, 20 % needed surgical intervention. Analyzed per year, the need for surgery decreased from almost 40 % in 2007 to 0 % in 2010 again increasing to 40 % although this did not reach statistical significance (p = 0.115). Median duration of "in-hospital fever" was 5 days (IQR, 3-8). The duration of fever correlated with pleural LDH (r = 0.324; p = 0.002) and pleural glucose (r = -0.248; p = 0.021) and was inversely correlated with pleural pH (r = -0.249; p = 0.046). Based on pleural PCR data, 85 % of PE were caused by Streptococcus pneumoniae (40 % serotype 1).

CONCLUSION

After introduction of a standardized primary medical approach (chest drain ± fibrinolysis) for PE in our institution, the need for surgical rescue interventions overall remained at 20 %, which is higher than in some other reports. Difference in microbiology or disease severity could not be proven.

Pneumococcal empyema and complicated pneumonias: global trends in incidence, prevalence, and serotype epidemiology

This review evaluates the serotype epidemiology of complicated pneumococcal pneumonia (CPP) during the period 1990–2012. PubMed and EMBASE were searched using the terms “empyema”, “complicated pneumonia”, “pleural infection”, “necrotizing pneumonia”, “pleural effusion”, “parapneumonic effusion”, “pneumatocele”, or “lung abscess”; “pneumococcal” or “Streptococcus pneumoniae”; and “serotype” for studies on the epidemiology of complicated pneumonias published from January 1, 1990 to October 1, 2013. Studies with data on incidence and serotypes were included; reviews, case reports, and conference abstracts were excluded. Of 152 papers, 84 fitted the inclusion criteria. A few pneumococcal serotypes were predominant causes of CPP, particularly serotypes 1, 19A, 3, 14, and 7F. CPP was a more common manifestation of pneumococcal disease among older (>2 years old) than younger children. The data support increases in both reported incidence rates and proportions of CPP in children and adults during the period 1990–2012; specific increases varied by geographic region. The proportions of serotype 3 and, particularly in Asia, serotype 19A CPP have increased, whereas most studies show declines in serotype 14. Serotype 1 has been a predominant cause of CPP since 1990, while antibiotic resistance was infrequent among serotype 1 isolates. The reported incidence and proportions of CPP among pneumonia cases steadily increased from 1990 to 2012. Several factors might account for these increases, including enhanced disease detection due to a higher index of suspicion, more sophisticated diagnostic assays, and changes in the prevalence of serotypes with capacity to invade the pleural space that were not targeted by the 7-valent pneumococcal conjugate vaccine (PCV7).

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.

Distribution of Streptococcus pneumoniae serotypes that cause parapneumonic empyema in Turkey

Streptococcus pneumoniae is the most common etiological cause of complicated pneumonia, including empyema. In this study, we investigated the serotypes of S. pneumoniae that cause empyema in children. One hundred fifty-six children who were diagnosed with pneumonia complicated with empyema in 13 hospitals in seven geographic regions of Turkey between 2010 and 2012 were included in this study. Pleural fluid samples were collected by thoracentesis and tested for 14 serotypes/serogroups using a Bio-Plex multiplex antigen detection assay. The serotypes of S. pneumoniae were specified in 33 of 156 samples. The mean age ± the standard deviation of the 33 patients was 6.17 ± 3.54 years (range, 0.6 to 15 years). All of the children were unvaccinated according to the vaccination reports. Eighteen of the children were male, and 15 were female. The serotypes of the non-7-valent pneumococcal conjugated vaccine (non-PCV-7), serotype 1, serotype 5, and serotype 3, were detected in eight (14.5%), seven (12.7%), and five (9.1%) of the samples, respectively. Serotypes 1 and 5 were codetected in two samples. The remaining non-PCV-7 serotypes were 8 (n = 3), 18 (n = 1), 19A (n = 1), and 7F/A (n = 1). PCV-7 serotypes 6B, 9V, 14, 19F, and 23F were detected in nine (16.3%) of the samples. The potential serotype coverages of PCV-7, PCV-10, and PCV-13 were 16.3%, 45.4%, and 60%, respectively. Pediatric parapneumonic empyema continues to be an important health problem despite the introduction of conjugated pneumococcal vaccines. Active surveillance studies are needed to monitor the change in S. pneumoniae serotypes that cause empyema in order to have a better selection of pneumococcal vaccines.

Clinical implications of pneumococcal serotypes: invasive disease potential, clinical presentations, and antibiotic resistance

Streptococcus pneumoniae can asymptomatically colonize the nasopharynx and cause a diverse range of illnesses. This clinical spectrum from colonization to invasive pneumococcal disease (IPD) appears to depend on the pneumococcal capsular serotype rather than the genetic background. According to a literature review, serotypes 1, 4, 5, 7F, 8, 12F, 14, 18C, and 19A are more likely to cause IPD. Although serotypes 1 and 19A are the predominant causes of invasive pneumococcal pneumonia, serotype 14 remains one of the most common etiologic agents of non-bacteremic pneumonia in adults, even after 7-valent pneumococcal conjugate vaccine (PCV7) introduction. Serotypes 1, 3, and 19A pneumococci are likely to cause empyema and hemolytic uremic syndrome. Serotype 1 pneumococcal meningitis is prevalent in the African meningitis belt, with a high fatality rate. In contrast to the capsule type, genotype is more closely associated with antibiotic resistance. CC320/271 strains expressing serotype 19A are multidrug-resistant (MDR) and prevalent worldwide in the era of PCV7. Several clones of MDR serotype 6C pneumococci emerged, and a MDR 6D clone (ST282) has been identified in Korea. Since the pneumococcal epidemiology of capsule types varies geographically and temporally, a nationwide serosurveillance system is vital to establishing appropriate vaccination strategies for each country.

Community-Acquired Pneumonia in the Conjugate Vaccine Era

Community-acquired pneumonia (CAP) remains one of the most common serious infections encountered among children worldwide. In this review, we highlight important literature and recent scientific discoveries that have contributed to our current understanding of pediatric CAP. We review the current epidemiology of childhood CAP in the developed world, appraise the state of diagnostic testing for etiology and prognosis, and discuss disease management and areas for future research in the context of recent national guidelines.

Viral and bacterial pathogens identification in children hospitalised for severe pneumonia and parapneumonic empyema

Pneumonia is caused by respiratory bacteria and/or viruses. Little is known if co-infections are an aggravating factor in hospitalised children with severe pneumonia. We studied the impact of respiratory pathogens on the severity of pneumonia. Between 2007 and 2009, 52 children hospitalised with a well-documented diagnosis of community-acquired pneumonia (CAP), with or without parapneumonic empyema (PPE), were enrolled in the study. The patients were classified into 2 groups: CAP + PPE (n = 28) and CAP (n = 24). The identification of respiratory viruses and bacteria in nasopharyngeal aspirates and pleural effusion samples were performed using conventional bacterial techniques and molecular assays. Using real-time multiplex PCR and antigen detection, Streptococcus pneumoniae was the main agent identified in 76% of the cases by molecular tests and BinaxNOW® in pleural fluid. A total of 8% of pleural fluid samples remained undiagnosed. In nasopharyngeal aspirates, rhinovirus, parainfluenza viruses, human metapneumovirus, and respiratory syncytial virus were detected in both CAP and CAP + PPE populations; however, the percentage of viral co-detection was significantly higher in nasopharyngeal aspirates from CAP + PPE patients (35%) compared with CAP patients (5%). In conclusion, viral co-detection was observed mainly in patients with more severe pneumonia. Molecular biology assays improved the pathogens detection in pneumonia and confirmed the S. pneumoniae detection by BinaxNOW® in pleural effusion samples. Interestingly, the main S. pneumoniae serotypes found in PPE are not the ones targeted by the heptavalent pneumococcal conjugate vaccine.

Current evidence for the management of paediatric parapneumonic effusions

BACKGROUND

Parapneumonic effusions (PPE) and empyema, secondary to bacterial pneumonia, are relatively uncommon but their prevalence is increasing lately. Even if their prognosis is generally good, they may still cause significant morbidity. The traditional treatment of PPE has been intravenous antibiotics and, when necessary, chest tube drainage. Open thoracotomy with decortication has usually been applied in case of failure of the traditional approach. Lately, the use of fibrinolysis and/or video-assisted thoracoscopic surgery (VATS) are utilized in the management of PPE; however, there is still little consensus on the most effective primary treatment.

SCOPE

In this article our goal was to summarize, based on up-to-date evidence, all the management options for PPE available to physicians and weigh the benefits and risks of the most popular ones, in an effort to figure out which one is superior as a first-line approach in children.

FINDINGS

A literature search of randomized and retrospective studies that pinpoint methods of evaluation and treatment of PPE was carried out in Medline and Scopus databases. Chest X-ray, ultrasound as well as microbiology and biochemical characteristics of the pleural fluid will facilitate decision-making. Small uncomplicated effusions resolve with antibiotics alone, larger ones require small-bore chest tube drainage and in case of complicated loculated PPE, fibrinolysis or VATS should be considered. Both methods promote faster drainage, reduce hospital stay and obviate the need for further interventions when used as first-line approach. However, primary treatment with VATS is not advised by the majority of studies as a first choice intervention, unless medical treatment has failed.

CONCLUSION

The main steps in treatment are diagnostic thoracocentesis and imaging, small percutaneous drainage, and considering fibrinolysis in complicated PPE. In case of failure, VATS should be the surgical method to be applied.

Bullous impetigo associated with Abiotrophia defectiva in an immunocompetent adult

Infection of humans by Abiotrophia defectiva, a nutritionally variant streptococcus, most commonly takes the form of endocarditis, though a variety of other manifestations ranging from central nervous system abscesses to orthopaedic infections have been seen. We report here what we believe is the first case of bullous impetigo associated with this organism.

Common childhood bacterial infections

Children with infectious diseases are commonly encountered in primary care settings. Identification of the subset of patients with bacterial infections is key in guiding the best possible management. Clinicians frequently care for children with infections of the upper respiratory tract, including acute otitis media, otitis externa, sinusitis, and pharyngitis. Conjunctivitis is not an uncommon reason for office visits. Bacterial pneumonia, urinary tract infections, and gastroenteritis are regularly seen. Over the last decade, a growing number of children have had infections of the skin and soft tissue, driven by the increased prevalence of infections caused by methicillin-resistant Staphylococcus aureus. The following review addresses the epidemiology and risk factors for specific infections and examines the clinical presentation and selection of appropriate diagnostic methods in such conditions. Methods to prevent these bacterial infections and recommendations for follow-up are suggested. Management of these infections requires that antimicrobial agents be used in a judicious manner in the outpatient setting. Such antibiotic therapy is recommended using both available clinical evidence and review of disease-specific treatment guidelines.

The management of community-acquired pneumonia in infants and children older than 3 months of age: clinical practice guidelines by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America

Evidenced-based guidelines for management of infants and children with community-acquired pneumonia (CAP) were prepared by an expert panel comprising clinicians and investigators representing community pediatrics, public health, and the pediatric specialties of critical care, emergency medicine, hospital medicine, infectious diseases, pulmonology, and surgery. These guidelines are intended for use by primary care and subspecialty providers responsible for the management of otherwise healthy infants and children with CAP in both outpatient and inpatient settings. Site-of-care management, diagnosis, antimicrobial and adjunctive surgical therapy, and prevention are discussed. Areas that warrant future investigations are also highlighted.

Pleural infection: changing bacteriology and its implications

The incidence of pleural infection continues to rise worldwide. Identifying the causative organism(s) is important to guide antimicrobial therapy. The bacteriology of pleural infection is complex and has changed over time. Recent data suggest that the bacterial causes of empyema are significantly different between adult and paediatric patients, between community-acquired and nosocomial empyemas and can vary among geographical regions of the world. Since the introduction of pneumococcal vaccines, a change has been observed in the distribution of the serotypes of Streptococcus pneumoniae in empyema. These observations have implications on therapy and vaccine strategies. Clinicians need to be aware of the local bacteriology of empyema in order to guide antibiotic treatment.

Emergence of parapneumonic empyema in the USA

BACKGROUND

Although recent reports suggest that the incidence of parapneumonic empyema has increased in several regions of the USA, national trends in disease burden are unknown. National trends in the incidence of parapneumonic empyema hospitalisations and changes in empyema by associated pathogens were examined.

METHODS

National hospitalisation data (1996-2008) were analysed and rates estimated using census estimates as denominators. Incidence rate ratios (IRR) compared 2008 with 1996 rates. Discharge diagnosis codes were used to characterise pathogens associated with empyema hospitalisations.

RESULTS

Overall, national parapneumonic empyema-related hospitalisation rates increased from 3.04 per 100,000 in 1996 to 5.98 per 100,000 in 2008, a 2.0-fold increase (95% CI 1.8 to 2.1). The increases were observed among children (IRR 1.9 (95% CI 1.4 to 2.7)) and adults aged 18-39, 40-64 and ≥65 years (IRR 1.8 (95% CI 1.5 to 2.1), 2.0 (95% CI 1.6 to 3.1) and 1.7 (95% CI 1.5 to 2.0), respectively). Overall, pneumococcal empyema rates remained relatively stable in all age groups whereas streptococcal- (non-pneumococcal) and staphylococcal-related empyema rates increased 1.9-fold and 3.3-fold, respectively, with consistent increases across age groups. The overall in-hospital case fatality ratio for parapneumonic empyema-related hospitalisations was 8.0% (95% CI 6.4% to 9.5%) in 1996 and 7.2% (95% CI 6.3% to 8.1%) in 2008 (p=0.395). Of the empyemas where study pathogens were listed (37.6%), staphylococcal-related empyema had the largest absolute increases across age groups and was associated with longer hospital stay and higher in-hospital mortality than other empyemas.

CONCLUSIONS

Although parapneumonic empyema-related hospitalisations remained relatively rare, they increased substantially during the study period. A number of pathogens, especially staphylococcus, contributed to this increase.

Molecular analysis improves pathogen identification and epidemiologic study of pediatric parapneumonic empyema

BACKGROUND

Parapneumonic empyema (PPE) is an increasingly common complication of bacterial pneumonia. Epidemiologic study is complicated by the low frequency of positive cultures. We sought to describe the epidemiology of PPE in children using molecular analysis of pleural fluid.

METHODS

We performed molecular testing for bacterial pathogens using archived pleural fluid from children hospitalized in 2009 with PPE. Real-time polymerase chain reaction (PCR) to detect Streptococcus pneumoniae, Staphylococcus aureus (including methicillin-resistant), Streptococcus pyogenes, Haemophilus influenzae, and Mycoplasma pneumoniae as well as PCR-based serotyping of S. pneumoniae was performed. Demographic, laboratory, and microbiologic data were abstracted.

RESULTS

Pleural fluid specimens from 63 children were available for PCR. By culture, a pathogen was isolated from blood and/or pleural fluid in 22 (35%) patients, with S. pneumoniae in 15 (24%), S. pyogenes in 3 (5%), and methicillin-resistant Staphylococcus aureus in 4 (6%). By PCR, a pathogen was detected in 53 (84%), including S. pneumoniae in 45 (71%). Compared with culture, PCR testing significantly increased detection of any pathogen (35% vs. 84%; P < 0.001) and of S. pneumoniae (24% vs. 71%; P < 0.001). Serotype 7F was the most common pneumococcal serotype detected. Comparison of culture-negative to culture-positive disease showed differences in both the pathogen profile and clinical outcomes.

CONCLUSIONS

Molecular analysis of pleural fluid more than doubled the detection of pathogens causing PPE. S. pneumoniae was the most common cause of both culture-positive and culture-negative PPE, although serotype distribution and outcomes differed.

Community-acquired Staphylococcus aureus pneumonia among hospitalized children in Hawaii

SUMMARY BACKGROUND

Invasive community acquired (CA) Staphylococcus aureus (SA) disease has been endemically observed in Hawaiian children. We wanted to evaluate the clinical, laboratory findings, and outcomes of methicillin-resistant SA (MRSA) and methicillin-susceptible SA (MSSA) associated pneumonia admissions.

METHODS

We performed retrospective chart reviews of 38 culture proven SA pneumonia patients admitted to a pediatric tertiary medical center in Hawaii between January 1996 to December 2007.

RESULTS

Twenty-six patients (68%) had MRSA and 12 patients (32%) had MSSA infection. The mean age of MRSA patients was 2.8 and 6.7 years for MSSA patients (P < 0.05). Pacific Islander and Native Hawaiian patients were affected disproportionately compared to non-Pacific Islander and Hawaiian groups (P < 0.0001). Demographic data, days of fever, tachypnea, hypoxia, and length of stay (LOS) were not significantly different between MRSA and MSSA infected patients. The mean LOS was 26.2 days (range 6-138 days); mean length of fever was 12.4 days. Seventy five percent (15 of 20) of patients who required intubation had MRSA. Twenty-one of the 29 (72%) total patients with pleural effusions had MRSA infection and all required chest tube placements. Two (5%) patients died; both had MRSA infection.

CONCLUSIONS

Younger Pacific Islander/Native Hawaiian children were affected disproportionately and had MRSA infection more frequently. MRSA infected patients appeared to have severe disease with frequent chest tube placement, intubation, and fatality. Overall, both MRSA and MSSA pneumonia resulted in prolonged hospitalization, multiple complications, and significant healthcare costs.

Pediatric complicated pneumonia and pneumococcal serotype replacement: trends in hospitalized children pre and post introduction of routine vaccination with Pneumococcal Conjugate Vaccine (PCV7)

Recent studies have described an increase in the incidence of complicated pneumonia in children, primarily caused by Streptococcus pneumoniae. The objective of this study was to determine if the incidence of complicated pneumonias in total and due to different pneumococcal serotypes has changed following the introduction of routine immunization with heptavalent pneumococcal conjugate vaccine (PCV7). A retrospective review of patients admitted to the Stollery Children's Hospital in Edmonton, Alberta with complicated pneumonia between July 1, 1997 and June 30, 2007 (5 years before and after the introduction of PCV7) was completed. There were 34 children in the pre- and 68 in the post-PCV7 era (14.31 and 19.91 per 10,000 discharges, respectively, p = 0.114). Patient characteristics were not significantly different, and pneumococcus was the most common organism isolated (pre: 21% (7/34); post: 26% (18/68), p = 0.515). In patients where serotype data was available, non-vaccine pneumococcal serotypes accounted for 67% (12/18) cases in the post-PVC7 era versus 14% (1/7) in the pre-PCV7 era (p = 0.031). The incidence of non-vaccine serotypes was 0.42 and 3.51 per 10,000 discharges in the pre- and post-PCV7 eras, respectively (p = 0.020). There has been a non-significant trend towards an increase in the incidence of complicated pneumonia following the introduction of PCV7. S. pneumoniae remains the predominant organism identified with non-vaccine serotypes now accounting for almost all cases. Although it is not clear if this increase is attributable to the use of PCV7, expanding pneumococcal serotype coverage has the potential to prevent complicated pneumonia.

National hospitalization trends for pediatric pneumonia and associated complications

OBJECTIVE

To determine current rates of and trends in hospitalizations for community-acquired pneumonia (CAP) and CAP-associated complications among children.

METHODS

We performed a cross-sectional, retrospective, cohort study by using the 1997, 2000, 2003, and 2006 Kids' Inpatient Database. National estimates for CAP and CAP-associated local and systemic complication rates were calculated for children < or =18 years of age. Patients with comorbid conditions or in-hospital birth status were excluded. Percentage changes were calculated by using 1997 (before heptavalent pneumococcal conjugate vaccine [PCV7]) and 2006 (after PCV7) data.

RESULTS

There were a total of 619,102 CAP discharges for 1997, 2000, 2003, and 2006, after application of inclusion and exclusion criteria. Overall rates of CAP discharges did not change substantially between 1997 and 2006, but stratification according to age revealed a 22% decrease for children <1 year of age, minimal change for children 1 to 5 years of age, and increases for children 6 to 12 years (22%) and > or =13 years (41%) of age. Systemic complication rates were highest among children <1 year of age but decreased by 36%. In all other age groups, systemic complication rates remained stable. Local complication rates increased 78% overall. Children 1 to 5 years of age had the highest local complication rates.

CONCLUSIONS

After the introduction of PCV7 in 2000, rates of CAP-associated systemic complications decreased only for children <1 year of age. Rates of pediatric CAP-associated local complications are increasing in all age groups.

Prevalence and risk factors of suppurative complications in children with pneumonia

AIM

To identify the baseline characteristics associated with suppurative complications in children with community-acquired primary pneumonia.

METHODS

A retrospective study included all children from 28 days to 15 years old, who presented with community-acquired pneumonia at two French hospitals from 1995 to 2003. Complicated pneumonia was defined by the presence of empyema and/or lung abscess.

RESULTS

Of 767 children with community-acquired pneumonia, 90 had suppurative complications: 83 cases of pleural empyema and seven cases of lung abscess. The mean prevalence of complicated pneumonia was 3% during the 1995-1998 period, and then steadily increased following a linear trend to reach 23% in 2003. Children with complicated pneumonia were older and had a longer symptomatic period preceding hospitalization. They were more likely to receive antibiotics, especially aminopenicillins (p < 0.01), and nonsteroidal anti-inflammatory drugs, especially ibuprofen (p < 0.001). In multivariable analysis, ibuprofen was the only preadmission therapy that was independently associated with complicated pneumonia [adjusted OR = 2.57 (1.51-4.35)].

CONCLUSION

This study confirms an association between the use of prehospital ibuprofen and suppurative pneumonic complications.

Molecular epidemiology of pediatric pneumococcal empyema from 2001 to 2007 in Utah

Utah had a high rate of pediatric pneumococcal empyema (PPE) prior to licensure of the pneumococcal conjugate vaccine (PCV-7) in 2000. The majority (62%) of PPE cases was due to nonvaccine serotypes, primarily Streptococcus pneumoniae serotype 1, multilocus sequence type (MLST) 227. PPE in Utah children has increased over the last decade. It is unclear whether the increase was due to serotype replacement or switch. In this study, we describe the incidence and molecular epidemiology of PPE by MLST in Utah children after the licensure of PCV-7. Empyema rates increased from 8.5/100,000 children in the state of Utah in 2001 to 12.5/100,000 children in 2007 (P = 0.006). Ninety-eight percent was due to nonvaccine serotypes (P < 0.001 when compared to the pre-PCV-7 period). PPE was primarily due to serotypes 1, 3, 19A, and 7F, with MLST demonstrating sequence types (ST) that were commonly present in the United States prior to licensure of PCV-7. Serotype switch was not documented. Replacement disease with common ST of serotypes 1,3, 7F, and 19A rather than serotype switch was responsible for the increase in PPE in Utah children.

Pediatric parapneumonic pleural effusion: epidemiology, clinical characteristics, and microbiological diagnosis

BACKGROUND

In recent years an increase in the incidence and severity of parapneumonic pleural effusion (PPE) in pediatric populations has been observed. Streptococcus pneumoniae remains the main causal agent. New molecular and antigen techniques have increased the microbiological diagnosis of this pathology.

OBJECTIVES

To describe the epidemiology and clinical characteristics of PPE in our population.

PATIENTS AND METHODS

Prospective study of patients under the age of 18 years admitted for PPE in a tertiary-care pediatric hospital in Barcelona (Spain) between September 2003 and December 2006.

RESULTS

One hundred ninety cases of PPE were diagnosed. The annual incidence of PPE in the population under 18 years of age increased from 19.9 cases per 100,000 in 2004 to 35.2 per 100,000 in 2006. S. pneumoniae was the main causal agent identified: 82.9% of the 21.6% patients with positive culture. Non-vaccine serotypes (NVS) predominated (81.5%), and serotype 1 was responsible for 38.5% of cases. The use of polymerase chain reaction (PCR) test to detect S. pneumoniae increased etiological diagnosis from 21.6% to 42.1%. Antigen assays used to detect pneumococcus in pleural fluid demonstrated 87.9% sensitivity and 100% specificity when PCR was used as the gold standard.

CONCLUSIONS

There has been an increase in the incidence of PPE that parallels the increase in CAP. S. pneumoniae remains the principal causal agent, and NVS clearly predominate. The use of PCR to detect S. pneumoniae substantially increases etiologic diagnosis. The use of antigen assays to detect pneumococcus in pleural fluid is a quick and sensitive diagnostic method, and thus a valid alternative to PCR.

Complicated parapneumonic effusion in Belgian children: increased occurrence before routine pneumococcal vaccine implementation

An increased occurrence of complicated parapneumonic effusions in children has been reported from the UK and USA. Data from mainland Europe are scarce. We investigated the incidence of complicated parapneumonic effusion and empyaema in children admitted to the University Hospital of Leuven between 1993 and 2005, an era when pneumococcal conjugated vaccination had not yet been implemented. Sixty-eight cases were identified. The incidence increased from 20-55/100,000 hospital admissions to 120-130/100,000 hospital admissions in 2005, with 50% of the cases occurring from 2003 onwards (late cohort). This increase occurred later than that reported in the UK and US, but is of similar magnitude. The median patient age was 3.6 years (range 0.5-17 years). The median duration of symptoms before admission was 4 days (quartile values 3-7 days). The median white blood cell (WBC) count was 15,450 WBC/mm3 (quartile values 11,300-21,200 WBC/mm3) and the median C-reactive protein (CRP) level was 242 mg/L (quartile values 143-344 mg/L). Patients in the late cohort seemed to have worse disease compared to early cohort patients; significantly higher pleural lactate dehydrogenase (LDH) level (P = 0,02), higher pleural WBC, lower pleural glucose level and significantly longer duration of hospitalisation in the later cohort (P < 0,05), possibly reflecting more severe disease. In both cohorts, Streptococcus pneumoniae was the most frequently isolated pathogen, with serogroup 1 prevailing. The occurrence of complicated parapneumonic effusion increased in Belgian children before pneumococcal vaccination was added to routine childhood immunisations. This increase is pronounced from 2003 onwards (late cohort) and, thus, occurred later than that reported in the UK and USA; several parameters point towards the occurrence of more serious disease in the late cohort patients.

Empyema associated with community-acquired pneumonia: a Pediatric Investigator's Collaborative Network on Infections in Canada (PICNIC) study

BACKGROUND

Although the incidence of serious morbidity with childhood pneumonia has decreased over time, empyema as a complication of community-acquired pneumonia continues to be an important clinical problem. We reviewed the epidemiology and clinical management of empyema at 8 pediatric hospitals in a period before the widespread implementation of universal infant heptavalent pneumococcal vaccine programs in Canada.

METHODS

Health records for children<18 years admitted from 1/1/00-31/12/03 were searched for ICD-9 code 510 or ICD-10 code J869 (Empyema). Empyema was defined as at least one of: thoracentesis with microbial growth from pleural fluid, or no pleural fluid growth but compatible chemistry or cell count, or radiologist diagnosis, or diagnosis at surgery. Patients with empyemas secondary to chest trauma, thoracic surgery or esophageal rupture were excluded. Data was retrieved using a standard form with a data dictionary.

RESULTS

251 children met inclusion criteria; 51.4% were male. Most children were previously healthy and those<or=5 years of age comprised 57% of the cases. The median length of hospitalization was 9 days. Admissions occurred in all months but peaked in winter. Oxygen supplementation was required in 77% of children, 75% had chest tube placement and 33% were admitted to an intensive care unit. While similarity in use of pain medication, antipyretics and antimicrobial use was observed, a wide variation in number of chest radiographs and invasive procedures (thoracentesis, placement of chest tubes) was observed between centers. The most common organism found in normally sterile samples (blood, pleural fluid, lung biopsy) was Streptococcus pneumoniae.

CONCLUSION

Empyema occurs most commonly in children under five years and is associated with considerable morbidity. Variation in management by center was observed. Enhanced surveillance using molecular methods could improve diagnosis and public health planning, particularly with regard to the relationship between immunization programs and the epidemiology of empyema associated with community-acquired pneumonia in children.

[Is the incidence of parapneumonic pleural effusion increasing?]

INTRODUCTION

Streptococcus pneumoniae is the microorganism most frequently associated with complicated pleural effusion. After the introduction of the heptavalent pneumococcal vaccine, there was a decline in the incidence of invasive pneumococcal disease and, to a lesser extent, in that of pneumonia. However, the incidence of empyema apparently increased. The antipneumococcal heptavalent vaccine was introduced in Spain in 2001.

OBJECTIVES

To determine whether the incidence of pleural effusion secondary to pneumonia has increased in hospitalized patients and to examine the possible influence of the antipneumococcal heptavalent vaccine on the incidence rate of parapneumonic effusions.

PATIENTS AND METHODS

Patients aged less than 16 years old admitted to our hospital with a diagnosis of pneumonia between 1999 and 2005 were retrospectively reviewed. We calculated the annual incidence rate of pleural effusion with respect to the total number of patients admitted with pneumonia and with respect to patients considered to have probable bacterial pneumonia, based on previously established criteria.

RESULTS

A total of 337 patients were analyzed, of which 213 (63.2%) met the criteria for a diagnosis of probable bacterial pneumonia. Pleural effusion was found in 34 patients (15.9%), and 13 of these effusions (38%) were complicated. No clear trend was detected in the annual incidence of probable bacterial pneumonia per 100 admitted patients, although the highest numbers were detected in the last two years of the study period. The percentage of complications (effusions) remained constant (mean: 16.28%). No differences were found in the effusion rate between vaccinated and unvaccinated patients (12.5% vs 18.6%).

CONCLUSIONS

The trend in the incidence of parapneumonic pleural effusions was parallel and proportional to that of probable bacterial pneumonia.

[Why are pediatric empyemas on the increase in Spain?]

There is a widespread perception among Spanish pediatricians that the incidence of empyema has significantly increased in the last few years, even though the objective information available is limited, and there is no specific active epidemiological surveillance system for this condition. In the present article, we review the situation of empyema in Spain, and discuss the main hypotheses put forward in the international literature to explain this increase, as well as the limitations of the sources available. Despite the scarcity of information, we draw the following conclusions: 1) the incidence of pediatric empyema is increasing in Spain, both generally and when caused by pneumococcus in particular; 2) the reason for this increase remains unknown, and to date no firm link has been established between this phenomenon and the heptavalent conjugate pneumococcal vaccine; and 3) this situation justifies the establishment of prospective systems for the surveillance and control of empyema and, once again, highlights the importance of developing active surveillance systems for pneumococcal disease.

Management of parapneumonic effusions in pediatrics: current practice

Pneumonia with associated complex pleural disease is a cause of significant morbidity among hospitalized children. The management of this patient population continues to be a challenge and varies even among single institutions. The article presented here reviews the management goals for pediatric patients hospitalized with complex parapneumonic effusions and provides updated summaries of both medical and surgical therapies.

[Epidemiology and clinical characteristics of childhood parapneumonic empyemas]

Several studies have reported an increasing incidence of childhood parapneumonic empyemas in various countries.

AIM OF THE STUDY

The aim of our study was to estimate the annual incidence of complicated community-acquired pneumonias in children during a 9-year period in a French area and to describe the epidemiological and clinical characteristics of these complications.

POPULATION AND METHODS

We have listed the children from 28 days to 15 years old, hospitalized in the 2 children hospitals of the Isere district for a community-acquired pneumonia complicated with a pleural empyema or a pulmonary abscess from 1995 to 2003.

RESULTS

During the study period, 90 children were hospitalized for a complicated pneumonia including 83 pleural empyemas and 7 isolated lung abscess. The average number of cases was 4 per year from 1995 to 1998 then increased since 1999 to reach 34 cases in 2003, according to a linear model (P<0,001). The incidence of the complicated pneumonia, plotted to the paediatric population of the area has gone up from 0.5 per 100000 to 13 per 100000 children between 1995 and 2003.

CONCLUSION

The incidence of the complicated pneumonias in children increased since 1999 in a French area. Additional investigations are necessary to identify the causes of this increase.