Pediatric Community-Acquired Pneumonia in the United States: Changing Epidemiology, Diagnostic and Therapeutic Challenges, and Areas for Future Research

A Retrospective Report on Simple Febrile Seizure Management in a Pediatric Emergency Department

OBJECTIVE

To determine whether pediatric emergency medicine physicians are compliant with the 9-year-old simple febrile seizure guideline created by the American Academy of Pediatrics (AAP).

METHODS

A retrospective chart review of patients, ages 6 to 60 months, who presented to the emergency department between May 2011 and December 2019. Key variables abstracted were urine, blood, nasal viral swab, and radiographic results.

RESULTS

The retrospective cohort of 285 children met inclusion criteria. Among 285 children, 342 studies were performed with a median of 1.2 studies per patient. There were 77 urine cultures obtained with 6 bacterial pathogens. Nasal viral swabs were performed on 65 children with 9 positive results. Blood cultures were obtained for 28 children and none were positive. Chest radiographs were performed on 37 children with 4 showing pneumonia.

CONCLUSION

The study results reflect areas of opportunity to update guidelines with a focus to consider obtaining urine studies, viral sampling, and chest x-rays.

Optimizing Diagnosis and Management of Community-acquired Pneumonia in the Emergency Department

Pneumonia is split into 3 diagnostic categories: community-acquired pneumonia (CAP), health care-associated pneumonia, and ventilator-associated pneumonia. This classification scheme is driven not only by the location of infection onset but also by the predominant associated causal microorganisms. Pneumonia is diagnosed in over 1.5 million US emergency department visits annually (1.2% of all visits), and most pneumonia diagnosed by emergency physicians is CAP.

Caregiver knowledge and attitudes relating to paediatric pneumonia and antimicrobial stewardship: a qualitative study

OBJECTIVE

The objective of this study was to understand caregiver perspectives and experiences relating to the treatment of paediatric community-acquired pneumonia (CAP).

DESIGN, SETTING AND PATIENTS

This was a phenomenological qualitative study involving interviews with caregivers of young children in Hamilton, Ontario. Caregivers were asked open-ended questions relating to germ theory, pneumonia and the role of antibiotic treatment. The principles of conventional content analysis guided the coding and synthesis of the transcribed interviews.

RESULTS

Eleven caregivers were interviewed. Many knew that antibiotics were not effective against all types of infections and stated that there was an increased risk of developing resistance with frequent use. However, there were misconceptions that probiotics effectively mitigated antibiotic side effects, and few were familiar with the potential long-term consequences of antibiotic use in children.There was variability in the perceived severity of paediatric CAP. Some participants thought that antibiotic treatment would accelerate recovery and prevent caregivers from feeling helpless. However, others also thought it was inappropriate for physicians to prescribe antibiotics solely to make the caregiver feel better. Many caregivers also felt strongly that clinical follow-up and discussions on treatment risks/benefits would be desirable to counteract feelings of helplessness that result from being sent home without a prescription.

CONCLUSION

Recognising that parents may have misperceptions about antibiotic use for CAP (and may seek antibiotics without strong rationale) can inform clinicians' efforts to better educate and support caregivers in the emergency department. Care strategies informed by caregiver experiences can improve parent-provider communication and reduce antibiotic misuse.

Multiplex PCR and Antibiotic Use in Children with Community-Acquired Pneumonia

Antibiotics are frequently prescribed to children with pneumonia, although viruses are responsible for most cases. We aimed to evaluate the impact of multiplex polymerase chain reaction (mPCR) on antibiotic use. We conducted a prospective study of children under 14 years of age admitted for suspected viral pneumonia, from October 2019 to June 2022 (except March-November 2020). A mPCR respiratory panel (FilmArray® 2plus, bioMérieux, Marcy-l'Étoile, France) was performed within 72 h of admission. Patients with positive reverse transcription PCR for respiratory syncytial virus, influenza, or SARS-CoV-2 were excluded. We compared the patients with historical controls (2017-2018) who had suspected viral pneumonia but did not undergo an aetiological study. We included 64 patients and 50 controls, with a median age of 26 months. The respiratory panel detected viral pathogens in 55 patients (88%), including 17 (31%) with co-infections. Rhinovirus/enterovirus (n = 26) and human metapneumovirus (n = 22) were the most common pathogens, followed by adenovirus and parainfluenza (n = 10). There were no statistically significant differences in the total antibiotic consumption (83% of cases and 86% of controls) or antibiotics given for ≥72 h (58% vs. 66%). Antibiotics were prescribed in 41% of the cases and 72% of the controls at discharge (p = 0.001). Ampicillin was the most commonly prescribed antibiotic among the patients (44% vs. 18% for controls, p = 0.004), while azithromycin was the most commonly prescribed among the controls (19% vs. 48% for patients and controls, respectively; p = 0.001). Our findings underscore the need for additional interventions alongside molecular diagnosis to reduce antibiotic usage in paediatric community-acquired pneumonia.

Antibiotic Prescribing for Lower Respiratory Tract Infections and Community-Acquired Pneumonia: An Italian Pediatric Emergency Department's Real-Life Experience

BACKGROUND

Lower respiratory tract infections (LRTIs) and community-acquired pneumonia (CAP) are among the most frequent reasons for referrals to the pediatric emergency department (PED). The aim of this study is to describe the management of antibiotic prescription in febrile children with LRTI or CAP admitted to a third-level PED and to investigate the different variables that can guide physicians in this decision-making.

METHODS

This is an observational, retrospective, monocentric study including patients < 14 years old who were presented to the PED for a febrile LRTI or CAP during the first six months of the year 2017. Demographic and clinical data, PED examinations, recommended therapy, and discharge modality were considered. Two multivariate logistic regression analyses were performed on patients with complete profiles to investigate the impact of demographic, laboratory, and clinical variables on antibiotic prescription and hospital admission.

RESULTS

This study included 584 patients with LRTI (n = 368) or CAP (n = 216). One hundred and sixty-eight individuals (28.7%) were admitted to the hospital. Lower age, higher heart rate, and lower SpO2 were associated with an increased risk of hospitalization. Antibiotics were prescribed to 495 (84.8%) patients. According to the multivariate logistic regression, the diagnosis and duration of fever were substantially linked with antibiotic prescription.

CONCLUSIONS

The present study reports real-life data about our PED experience. A high rate of antibiotic prescription was noted. In the future, it is necessary to improve antibiotic stewardship programs to increase clinical adherence to guidelines.

Clinical Efficiency of Metagenomic Next-Generation Sequencing in Sputum for Pathogen Detection of Patients with Pneumonia According to Disease Severity and Host Immune Status

Purpose

Severe pneumonia causes the highest mortality rate in immunocompromised patients. This study aimed to investigate the pathogen diagnostic efficacy of metagenomic next-generation sequencing (mNGS) using sputum sample in patients with pneumonia according to patients' disease severity and immune conditions.

Patients and Methods

A total of 180 patients suffering from pneumonia were recruited, and sputum samples were collected in duplicate for pathogen detection by both conventional microbiological tests (CMT) and mNGS. Then, the performance of pathogen identification was examined between two methods, according to disease severity and patients' immune status.

Results

In comparison to CMT, mNGS had higher positivity rates in all patients with pneumonia (85.0% vs 62.2%, P=9.445e-07). The most commonly detected microorganism in sputum of pneumonia patients was Acinetobacter baumannii (42/180, 23.3%) in bacterum level, Candida albicans in fungus level (44/180, 24.4%), and Human herpesvirus 1 (39/180, 27.5%) in virus level. However, for mNGS results, Candida albicans in 34.9% of positive patients, and Human herpesvirus 1 in 7.7% of positive cases were confirmed as pathogens causing pneumonia. Acinetobacter baumannii detected by mNGS in 75% of positive patients was diagnosed as pathogen of pneumonia. The microorganism profile of sputum mNGS differed according to disease severity and immune status of patients. Pneumocystis jirovecii was more likely to infect immunocompromised patients (P=0.002). Pseudomonas aeruginosa (14.8% vs 0.0%, P=0.008) and Human herpesvirus 1 (26.1% vs 5.3%, P=0.004) had higher infection rate in patients with severe pneumonia compared with non-severe cases. mNGS had overwhelming advantages over CMT in detecting a lot of microorganisms including Streptococcus pneumoniae, Enterococcus faecium, Pneumocystis jirovecii, and majority of viruses.

Conclusion

mNGS is a complementary tool of CMT for detecting suspected pathogens for patients with lower respiratory infections. The interpretation of opportunistic pathogens identified by mNGS is challenging, and needs comprehensive consideration of sequencing data and clinical factors.

Impact of Adjunct Corticosteroid Therapy on Quality of Life for Children With Suspected Pneumonia

OBJECTIVE

To determine the association between adjunct corticosteroid therapy and quality of life (QoL) outcomes in children with signs and symptoms of lower respiratory tract infection and clinical suspicion for community-acquired pneumonia (CAP) in the emergency department (ED).

METHODS

Secondary analysis from a prospective cohort study of children aged 3 months to 18 years with signs and symptoms of LRTI and a chest radiograph for suspected CAP in the ED, excluding children with recent (within 14 days) systemic corticosteroid use. The primary exposure was receipt of corticosteroids during the ED visit. Outcomes were QoL measures and unplanned visits. Multivariable regression was used to evaluate the association between corticosteroid therapy and outcomes.

RESULTS

Of 898 children, 162 (18%) received corticosteroids. Children who received corticosteroids were more frequently boys (62%), Black (45%), had history of asthma (58%), previous pneumonia (16%), presence of wheeze (74%), and more severe illness at presentation (6%). Ninety-six percent were treated for asthma as defined by report of asthma or receipt of ß-agonist in the ED. Receipt of corticosteroids was not associated with QoL measures: days of activity missed (adjusted incident rate ratio [aIRR], 0.84; 95% confidence interval [CI], 0.63-1.11) and days of work missed (aIRR, 0.88; 95% CI, 0.60-1.27). There was a statistically significant interaction between age (>2 years) and corticosteroids receipt; the patients had fewer days of activity missed (aIRR, 0.62; 95% CI, 0.46-0.83), with no effect on children 2 years or younger (aIRR, 0.83; 95% CI, 0.54-1.27). Corticosteroid treatment was not associated with unplanned visit (odds ratio, 1.37; 95% CI, 0.69-2.75).

CONCLUSIONS

In this cohort of children with suspected CAP, receipt of corticosteroids was associated with asthma history and was not associated with missed days of activity or work, except in a subset of children aged older than 2 years.

The effect of early childhood respiratory infections and pneumonia on lifelong lung function: a systematic review

Early childhood respiratory infections, including pneumonia, are an important global public health issue, with more than 40 million annual cases resulting in approximately 650 000 deaths. A growing number of published studies have examined the effects of early childhood lower respiratory tract infections (LRTIs) or pneumonia on lung function, particularly as part of large early-life exposure studies. To our knowledge, there is no published systematic review of these data. We searched PubMed, Embase, and Web of Science for studies published between database inception and May 12, 2022. Case-control, cohort, and cross-sectional studies were included if they reported forced expiratory volume in 1 s (FEV1) or forced vital capacity (FVC) values of participants older than 5 years. Article titles and abstracts were screened in Rayyan before retrieval, assessment, and data extraction of the full text. Primary outcome measures were differences in mean FEV1 or FVC values between exposed groups (ie, children aged ≤5 years with LRTIs) and non-exposed groups. This study is registered with PROSPERO, CRD42021265295. Database searches yielded 3070 articles, and 14 studies were included in this systematic review, providing a total of 23 276 participants, including 9969 children and 13 307 adults. Eight of 14 articles reported significant reductions in FEV1 values, and six of 12 studies reported reductions in FVC values in children and adults with a history of early childhood LRTIs or pneumonia, compared with unexposed controls (p<0·05). Most studies reporting reductions in lung function described deficits consistent with a restrictive spirometry pattern. Only two of 14 studies reported data from low-income and middle-income countries or disadvantaged populations in middle-income and high-income countries, and there were scarce data available on the effect of LRTI severity and recurrence on lung function. LRTIs in early childhood could be associated with a restrictive spirometry pattern in later childhood and adulthood. Data are needed from low-income and middle-income nations, and from disadvantaged populations in middle-income and high-income countries in which early childhood respiratory infection burden is disproportionately high. Data are also needed on the effect of LRTI severity and recurrence on future lung function.

Evaluation of a Pediatric Community-Acquired Pneumonia Antimicrobial Stewardship Intervention at an Academic Medical Center

(1) Background: Pneumonia is the leading diagnosis associated with antibiotic use in hospitalized children. The Infectious Diseases Society of America published pediatric community-acquired pneumonia (CAP) guidelines in 2011, but adherence to recommendations varies across institutions. The purpose of this study was to evaluate the impact of an antimicrobial stewardship intervention on antibiotic prescribing in pediatric patients admitted to an academic medical center. (2) Methods: This single-center pre/post-intervention evaluation included children admitted for CAP during three time periods (pre-intervention and post-intervention groups 1 and 2). The primary outcomes were changes in inpatient antibiotic selection and duration following the interventions. Secondary outcomes included discharge antibiotic regimens, length of stay, and 30-day readmission rates. (3) Results: A total of 540 patients were included in this study. Most patients were under five years of age (69%). Antibiotic selection significantly improved, with prescriptions for ceftriaxone decreasing (p < 0.001) and ampicillin increasing (p < 0.001) following the interventions. Antibiotic duration decreased from a median of ten days in the pre-intervention group and post-intervention group 1 to eight days in post-intervention group 2. (4) Conclusions: Our antibiotic stewardship intervention directed at pediatric CAP treatment resulted in improved antibiotic prescriptions and provides data that can be used to further educate providers at our institution.

Concordance in pathogen identification at the upper and lower respiratory tract of children with severe pneumonia

BACKGROUND

Nasopharyngeal swabs are taken to determine the causative agent of community acquired pneumonia (CAP), while the reliability of upper respiratory tract sampling as a proxy for lower respiratory tract infections is still unclear.

METHODS

Nasopharyngeal (NP) swabs, bronchoalveolar lavage (BAL) fluid samples and clinical data were collected from 153 hospitalized children between 3 months and 14 years of age with severe CAP, enrolled from March to June 2019. Written informed consent for the storage and use of the samples for further studies was obtained from the parents or caregivers. Putative pathogens were detected using a sensitive, high-throughput GeXP-based multiplex PCR and qPCR.

RESULTS

The same bacterial species in paired samples were found in 29 (23.4%) and the same viral species in 52 (27.5%) of the patients. moderate concordance was found for Mycoplasma pneumoniae (ĸ=0.64), followed by Haemophilus influenzae (ĸ=0.42). The strongest discordance was observed for human adenovirus and also for Pseudomonas aeruginosa, the latter was exclusively detected in BAL samples. In the adenovirus cases strong concordance was associated with high viral loads in the NP swabs.

CONCLUSION

The variation in concordance in pathogen detection in the upper and lower respiratory tract of children with severe pneumonia is generally high but varies depending on the species. Novel and impactful insights are the concordance between NP and BAL detection for M. pneumoniae and H. influenzae and the strong correlation between high adenoviral loads in NP swabs and detection in BAL fluid.

Pathogen spectra in hospitalised and nonhospitalised children with community-acquired pneumonia

Background

Paediatric community-acquired pneumonia (CAP) is a leading cause of paediatric morbidity. However, particularly for outpatients with paediatric CAP, data on aetiology and management are scarce.

Methods

The prospective pedCAPNETZ study multicentrically enrols children and adolescents with outpatient-treated or hospitalised paediatric CAP in Germany. Blood and respiratory specimens were collected systematically, and comprehensive analyses of pathogen spectra were conducted. Follow-up evaluations were performed until day 90 after enrolment.

Results

Between December 2014 and August 2020, we enrolled 486 children with paediatric CAP at eight study sites, 437 (89.9%) of whom had radiographic evidence of paediatric CAP. Median (interquartile range) age was 4.5 (1.6-6.6) years, and 345 (78.9%) children were hospitalised. The most prevalent symptoms at enrolment were cough (91.8%), fever (89.2%) and tachypnoea (62.0%). Outpatients were significantly older, displayed significantly lower C-reactive protein levels and were significantly more likely to be symptom-free at follow-up days 14 and 90. Pathogens were detected in 90.3% of all patients (one or more viral pathogens in 68.1%; one or more bacterial strains in 18.7%; combined bacterial/viral pathogens in 4.1%). Parainfluenza virus and Mycoplasma pneumoniae were significantly more frequent in outpatients. The proportion of patients with antibiotic therapy was comparably high in both groups (92.4% of outpatients versus 86.2% of hospitalised patients).

Conclusion

We present first data on paediatric CAP with comprehensive analyses in outpatients and hospitalised cases and demonstrate high detection rates of viral pathogens in both groups. Particularly in young paediatric CAP patients with outpatient care, antibiotic therapy needs to be critically debated.

Modern approaches at the management of children with community-acquired pneumonia

Experts of The Union of Pediatricians of Russia have developed current clinical guidelines for management of children with community-acquired pneumonia, which were approved by the Scientific and Practice Council of Ministry of Public Health of the Russian Federation in January 2022. Particular attention is paid to the etiological structure, modern classification, diagnostic tests and flagship approaches to antibacterial therapy of community-acquired pneumonia in children based on the principles of evidentiary medicine. 

PLGA-Based Micro/Nanoparticles: An Overview of Their Applications in Respiratory Diseases

Respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are critical areas of medical research, as millions of people are affected worldwide. In fact, more than 9 million deaths worldwide were associated with respiratory diseases in 2016, equivalent to 15% of global deaths, and the prevalence is increasing every year as the population ages. Due to inadequate treatment options, the treatments for many respiratory diseases are limited to relieving symptoms rather than curing the disease. Therefore, new therapeutic strategies for respiratory diseases are urgently needed. Poly (lactic-co-glycolic acid) micro/nanoparticles (PLGA M/NPs) have good biocompatibility, biodegradability and unique physical and chemical properties, making them one of the most popular and effective drug delivery polymers. In this review, we summarized the synthesis and modification methods of PLGA M/NPs and their applications in the treatment of respiratory diseases (asthma, COPD, cystic fibrosis (CF), etc.) and also discussed the research progress and current research status of PLGA M/NPs in respiratory diseases. It was concluded that PLGA M/NPs are the promising drug delivery vehicles for the treatment of respiratory diseases due to their advantages of low toxicity, high bioavailability, high drug loading capacity, plasticity and modifiability. And at the end, we presented an outlook on future research directions, aiming to provide some new ideas for future research directions and hopefully to promote their widespread application in clinical treatment.

The development of a novel natural language processing tool to identify pediatric chest radiograph reports with pneumonia

Objective

Chest radiographs are frequently used to diagnose community-acquired pneumonia (CAP) for children in the acute care setting. Natural language processing (NLP)-based tools may be incorporated into the electronic health record and combined with other clinical data to develop meaningful clinical decision support tools for this common pediatric infection. We sought to develop and internally validate NLP algorithms to identify pediatric chest radiograph (CXR) reports with pneumonia.

Materials and methods

We performed a retrospective study of encounters for patients from six pediatric hospitals over a 3-year period. We utilized six NLP techniques: word embedding, support vector machines, extreme gradient boosting (XGBoost), light gradient boosting machines Naïve Bayes and logistic regression. We evaluated their performance of each model from a validation sample of 1,350 chest radiographs developed as a stratified random sample of 35% admitted and 65% discharged patients when both using expert consensus and diagnosis codes.

Results

Of 172,662 encounters in the derivation sample, 15.6% had a discharge diagnosis of pneumonia in a primary or secondary position. The median patient age in the derivation sample was 3.7 years (interquartile range, 1.4-9.5 years). In the validation sample, 185/1350 (13.8%) and 205/1350 (15.3%) were classified as pneumonia by content experts and by diagnosis codes, respectively. Compared to content experts, Naïve Bayes had the highest sensitivity (93.5%) and XGBoost had the highest F1 score (72.4). Compared to a diagnosis code of pneumonia, the highest sensitivity was again with the Naïve Bayes (80.1%), and the highest F1 score was with the support vector machine (53.0%).

Conclusion

NLP algorithms can accurately identify pediatric pneumonia from radiography reports. Following external validation and implementation into the electronic health record, these algorithms can facilitate clinical decision support and inform large database research.

Epidemiology and surveillance implications of community-acquired pneumonia in children

Community-acquired pneumonia (CAP) is the single largest infectious cause of hospitalization and death in children worldwide. With improved immunizations, the incidence of bacterial pneumonia and the number of colonized bacteria have decreased. However, respiratory viruses are still an important cause of CAP, especially as new infectious agents such severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerge. The SARS-CoV-2 virus emerged in 2019 and caused the current coronavirus disease 2019 pandemic. Therefore, it is necessary to elucidate the epidemiology and causative pathogens of CAP. Recently, the Pneumonia and Respiratory Disease Study Group, affiliated with the Korean Academy of Pediatric Allergy and Respiratory Disease, investigated the causative pathogens of respiratory infections in children hospitalized with CAP, the serotype of Streptococcus pneumoniae, and the prevalence of Mycoplasma pneumoniae with gene mutations. Antibiotic resistance and serotype test results can determine the use of empirical antibiotics. Moreover, it is possible to help develop future vaccines by comparing bacterial culture results with vaccine serotype and identifying the changes and prevalence of each serotype. Therefore, we will perform continuous national surveillance and monitor the epidemiology of respiratory pathogens in Korea and worldwide. The surveillance of these respiratory infections can play a role in monitoring the emergence of new infectious diseases such as SARS-CoV-2.

Efficacy and safety of Chinese herbal medicine for pneumonia convalescence in children: A systematic review and meta-analysis

Background: Chinese herbal medicine (CHM) has advantages in treating sequela symptoms of pediatric pneumonia convalescence. Hence, this study aims to evaluate the efficacy and safety of CHM using a meta-analysis approach.

Methods: The randomized controlled trials (RCTs) that met the search strategy were selected from seven databases from the inception date to December 17, 2021. Based on the Cochrane handbook, the quality of the selected studies was assessed using the risk of bias. Data were expressed as relative risk (RR) or mean difference (MD) and with 95% confidence interval (CI). Subgroup analyses and sensitivity analyses were performed. The Grading Recommendation Assessment, Development, and Evaluation (GRADE) method was used to assess the evidence certainty.

Result: Twenty RCTs with 2,241 participants were identified using the search criteria. CHMs included Danshen injection, Liujunzi decoction, Qingfei Tongluo decoction, Yiqi Huoxue decoction, Yupingfeng granule, XiaoErFeiKe granule, Sha-Sheng-Mai-Dong decoction, and so on. Results indicated that CHM combined with Western medicine (WM) or CHM alone improved the total clinical effective rate (RR = 1.22; 95% CI: 1.15–1.29), reduced cough relief time (MD = −2.16; 95% CI: −2.46 to −1.85), lung rales disappearance time (MD = −1.82; 95% CI: −2.17 to −1.47), and length of hospital stay (MD = −2.01, 95% CI: −3.81 to −0.22) in the treatment of pneumonia convalescence in children. However, there was no significant statistical difference regarding the incidence of adverse reactions (RR = 0.57; 95% CI: 0.23–1.43).

Systematic Review Registration:https://www.crd.york.ac.uk/PROSPERO/; Identifier CRD42022298936

Effect of zinc versus vitamin A supplementation on pediatric patients with community-acquired pneumonia

Background: Community-acquired pneumonia (CAP) is one of the most common infectious diseases affecting the respiratory tract and is responsible for a high mortality rate in children less than 5 years of age. The mortality rate due to CAP is much higher in low/middle-income countries than in high-income countries due to malnutrition and different micronutrient deficiencies that weaken the immune system.

Aim: The aim of this study was to compare the effects of zinc and vitamin A, as two elements of micronutrient agents, on the recovery rate of children suffering from CAP aged from 6 months to 5 years. The length of hospital stays was also investigated.

Method: A comparative, randomized, open-label, controlled, interventional study was carried out among children less than 5 years of age in the pediatric intensive care unit (PICU) diagnosed with CAP who were randomly divided into three groups. In addition to the standard therapy, group 1 was given zinc, group 2 was given vitamin A, and group 3 was the control group, given the standard therapy only. We compared the three groups in terms of recovery rate and hospital stay.

Result: The duration of hospitalization following zinc and vitamin A supplementation was reduced by an average of 3.21 days (95% CI: 5.01–1.41, p = 0.01) and 2.43 days (95% CI: 4.29–0.57, p = 0.01), respectively, compared to the control group. In addition, the two groups of vitamin A and zinc supplementation were associated with a shorter duration of pneumonic effusion (p < 0.001) in comparison to the control group. Additionally, there was no significant difference between the effects of zinc and vitamin A when compared to each other in terms of duration of hospital stay and pneumatic effusion.

Conclusion: The administration of zinc or vitamin A supplementation proved to be useful as an add-on therapy in community-acquired pneumonia, where it reduced the length of hospital stay and the duration of pneumonic effusion in pneumonic children less than 5 years of age.

Improving Suspected Pulmonary Infection Diagnosis by Bronchoalveolar Lavage Fluid Metagenomic Next-Generation Sequencing: a Multicenter Retrospective Study

Metagenomic next-generation sequencing (mNGS) has been gradually applied to clinical practice due to its unbiased characteristics of pathogen detection. However, its diagnostic performance and clinical value in suspected pulmonary infection need to be evaluated. We systematically reviewed the clinical data of 246 patients with suspected pulmonary infection from 4 medical institutions between January 2019 and September 2021. The diagnostic performances of mNGS and conventional testing (CT) were systematically analyzed based on bronchoalveolar lavage fluid (BALF). The impacts of mNGS and CT on diagnosis modification and treatment adjustment were also assessed. The positive rates of mNGS and CT were 47.97% and 23.17%, respectively. The sensitivity of mNGS was significantly higher than that of CT (53.49% versus 23.26%, P < 0.01), especially for infections of Mycobacterium tuberculosis (67.86% versus 17.86%, P < 0.01), atypical pathogens (100.00% versus 7.14%, P < 0.01), viruses (92.31% versus 7.69%, P < 0.01), and fungi (78.57% versus 39.29%, P < 0.01). The specificity of mNGS was superior to that of CT, with no statistical difference (90.32% versus 77.42%, P = 0.167). The positive predictive value (PPV) and negative predictive value (NPV) of mNGS were 97.46% and 21.88%, respectively. Diagnosis modification and treatment adjustment were conducted in 32 (32/246, 13.01%) and 23 (23/246, 9.35%) cases, respectively, according to mNGS results only. mNGS significantly improved the diagnosis of suspected pulmonary infection, especially infections of M.tuberculosis, atypical pathogens, viruses, and fungi, and it demonstrated the pathogen distribution of pulmonary infections. It is expected to be a promising microbiological detection and diagnostic method in clinical practice.

IMPORTANCE Pulmonary infection is a heterogeneous and complex infectious disease with high morbidity and mortality worldwide. In clinical practice, a considerable proportion of the etiology of pulmonary infection is unclear, microbiological diagnosis being challenging. Metagenomic next-generation sequencing detects all nucleic acids in a sample in an unbiased manner, revealing the microbial community environment and organisms and improving the microbiological detection and diagnosis of infectious diseases in clinical settings. This study is the first multicenter, large-scale retrospective study based entirely on BALF for pathogen detection by mNGS, and it demonstrated the superior performance of mNGS for microbiological detection and diagnosis of suspected pulmonary infection, especially in infections of Mycobacterium tuberculosis, atypical pathogens, viruses, and fungi. It also demonstrated the pathogen distribution of pulmonary infections in the real world, guiding targeted treatment and improving clinical management and prognoses.

Clinical evaluation of metagenomic next-generation sequencing for detecting pathogens in bronchoalveolar lavage fluid collected from children with community-acquired pneumonia

This study is to evaluate the usefulness of pathogen detection using metagenomic next-generation sequencing (mNGS) on bronchoalveolar lavage fluid (BALF) specimens from children with community-acquired pneumonia (CAP). We retrospectively collected BALF specimens from 121 children with CAP at Tianjin Children's Hospital from February 2021 to December 2021. The diagnostic performances of mNGS and conventional tests (CT) (culture and targeted polymerase chain reaction tests) were compared, using composite diagnosis as the reference standard. The results of mNGS and CT were compared based on pathogenic and non-pathogenic organisms. Pathogen profiles and co-infections between the mild CAP and severe CAP groups were also analyzed. The overall positive coincidence rate was 86.78% (105/121) for mNGS and 66.94% (81/121) for CT. The proportion of patients diagnosed using mNGS plus CT increased to 99.18%. Among the patients, 17.36% were confirmed only by mNGS; Streptococcus pneumoniae accounted for 52.38% and 23.8% of the patients were co-infected. Moreover, Bordetella pertussis and Human bocavirus (HBoV) were detected only using mNGS. Mycoplasma pneumoniae, which was identified in 89 (73.55%) of 121 children with CAP, was the most frequent pathogen detected using mNGS. The infection rate of M. pneumoniae in the severe CAP group was significantly higher than that in the mild CAP group (P = 0.007). The symptoms of single bacterial infections (except for mycoplasma) were milder than those of mycoplasma infections. mNGS identified more bacterial infections when compared to the CT methods and was able to identify co-infections which were initially missed on CT. Additionally, it was able to identify pathogens that were beyond the scope of the CT methods. The mNGS method is a powerful supplement to clinical diagnostic tools in respiratory infections, as it can increase the precision of diagnosis and guide the use of antibiotics.

Ventilator-associated pneumonia is linked to a worse prognosis than community-acquired pneumonia in children

BACKGROUND

Around 12-20% of patients with community-acquired pneumonia (CAP) require critical care. Ventilator-associated pneumonia (VAP) is the second cause of nosocomial infection in Paediatric Intensive Care Units (PICU). As far as we know, there are no studies comparing both types of pneumonia in children, thus it remains unclear if there are differences between them in terms of severity and outcomes.

OBJECTIVE

The aim was to compare clinical and microbiological characteristics and outcomes of patients with severe CAP and VAP.

METHODS

A retrospective descriptive study, including patients diagnosed of VAP and CAP, with a positive respiratory culture and under mechanical ventilation, admitted to the PICU from 2015 to 2019.

RESULTS

238 patients were included; 163 (68.4%) with CAP, and 75 (31.5%) with VAP. Patients with VAP needed longer mechanical ventilation (14 vs. 7 days, p<0.001) and more inotropic support (49.3 vs. 30.7%, p = 0.006). Patients with VAP had higher mortality (12 vs. 2.5%, p = 0.005). Enterobacterales were more involved with VAP than with CAP (48 vs. 9%, p<0.001). Taking into account only the non-drug sensitive microorganisms, patients with VAP tended to have more multidrug-resistant bacteria (30 vs. 10.8%, p = 0.141) than patients with CAP.

CONCLUSION

Patients with VAP had worse prognosis than patients with CAP, needing longer mechanical ventilation, more inotropic support and had higher mortality. Patients with VAP were mainly infected by Enterobacterales and had more multidrug resistant microorganisms than patients with CAP.

Analysis of national surveillance of respiratory pathogens for community-acquired pneumonia in children and adolescents

Background

Respiratory infections among children, particularly community-acquired pneumonia (CAP), is a major disease with a high frequency among outpatient and inpatient visits. The causes of CAP vary depending on individual susceptibility, the epidemiological characteristics of the community, and the season. We performed this study to establish a nationwide surveillance network system and identify the causative agents for CAP and antibiotic resistance in Korean children with CAP.

Methods

The monitoring network was composed of 28 secondary and tertiary medical institutions. Upper and lower respiratory samples were assayed using a culture or polymerase chain reaction (PCR) from August 2018 to May 2020.

Results

A total of 1023 cases were registered in patients with CAP, and PCR of atypical pneumonia pathogens revealed 422 cases of M. pneumoniae (41.3%). Respiratory viruses showed a positivity rate of 65.7% by multiplex PCR test, and human rhinovirus was the most common virus, with 312 cases (30.5%). Two hundred sixty four cases (25.8%) were isolated by culture, including 131 cases of S. aureus (12.8%), 92 cases of S. pneumoniae (9%), and 20 cases of H. influenzae (2%). The cultured, isolated bacteria may be colonized pathogen. The proportion of co-detection was 49.2%. The rate of antibiotic resistance showed similar results as previous reports.

Conclusions

This study will identify the pathogens that cause respiratory infections and analyze the current status of antibiotic resistance to provide scientific evidence for management policies of domestic respiratory infections. Additionally, in preparation for new epidemics, including COVID-19, monitoring respiratory infections in children and adolescents has become more important, and research on this topic should be continuously conducted in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07263-z.

Nuclease activity: an exploitable biomarker in bacterial infections

INTRODUCTION

In the increasingly challenging field of clinical microbiology, diagnosis is a cornerstone whose accuracy and timing are crucial for the successful management, therapy, and outcome of infectious diseases. Currently employed biomarkers of infectious diseases define the scope and limitations of diagnostic techniques. As such, expanding the biomarker catalog is crucial to address unmet needs and bring about novel diagnostic functionalities and applications.

AREAS COVERED

This review describes the extracellular nucleases of 15 relevant bacterial pathogens and discusses the potential use of nuclease activity as a diagnostic biomarker. Articles were searched for in PubMed using terms: "nuclease", "bacteria", "nuclease activity" or "biomarker". For overview sections, original and review articles between 2000 and 2019 were searched for using terms: "infections", "diagnosis", "bacterial", "burden", "challenges". Informative articles were selected.

EXPERT OPINION

Using the catalytic activity of nucleases offers new possibilities compared to established biomarkers. Nucleic acid activatable reporters in combination with different transduction platforms and delivery methods can be used to detect disease-associated nuclease activity patterns in vitro and in vivo for prognostic and diagnostic applications. Even when these patterns are not obvious or of unknown etiology, screening platforms could be used to identify new disease reporters.

Impact of Cell-Free Next-Generation Sequencing on Management of Pediatric Complicated Pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) is common in pediatrics. More severe complicated CAP (cCAP) requires broad-spectrum empirical therapy. Cell-free plasma next-generation sequencing (cfNGS), a DNA-based diagnostic tool, could be used to guide therapy. We retrospectively compared the pathogen identification rate of cfNGS to that of standard culture methods and assessed the impact of cfNGS on antibiotic therapy in children hospitalized for cCAP.

METHODS

We conducted a retrospective review of children aged 3 months to 18 years hospitalized for cCAP with cfNGS results from January 24, 2018, to December 31, 2020. We compared the positivity rate of conventional microbiologic diagnostic testing with that of cfNGS and the impact on clinical management, including changes in antibiotic therapy.

RESULTS

We identified 46 hospitalized children with cCAP with cfNGS results. Of these children, 34 also had blood cultures (1 positive for pathogen; 3%) and 37 had pleural fluid cultures (10 positive for pathogen; 27%). Of the 46 children, positive cfNGS testing results were positive for pathogen in 45 (98%), with the causative pathogen identified in 41 (89%). cfNGS was the only method for pathogen identification in 32 children (70%). cfNGS results changed management in 36 (78%) of 46 children, with the antibiotic spectrum narrowed in 29 (81%).

CONCLUSIONS

cfNGS provided a higher diagnostic yield in our pediatric cCAP cohort compared with conventional diagnostic testing and affected management in 78% of children. Prospective studies are needed to better characterize the clinical outcome, cost-effectiveness, and antimicrobial stewardship benefits of cfNGS in pediatric cCAP.

Unexpected Pneumonia Diagnosis From Pediatric Abdominal Pain: A Case Report

Abdominal pain in the context of fever, tachypnea, or cough is a known presentation of pneumonia in preschool-aged children. We describe a 4-year-old male who presented to a pediatric emergency department with abdominal pain and decreased appetite. During his abdominal pain workup, he was found to have pneumonia complicated by pleural effusion and pneumothorax. It is critical for pediatric providers to be aware of age-based differentials.

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.

Ambient NO2 is associated with Streptococcus pneumoniae-induced pneumonia in children and increases the minimum inhibitory concentration of penicillin

The present study aimed to assess the correlation between ambient air pollutants and Streptococcus pneumoniae (S. pneumoniae)-induced pneumonia in children and retrospectively reviewed the daily data regarding S. pneumoniae from children with pneumonia in a tertiary hospital of Hangzhou City, between January 1st, 2018, and December 31st, 2018. The excess risk (ER) of NO₂ with regard to the daily number of S. pneumoniae isolates obtained from the respiratory tract specimens of children with pneumonia was 13.31% (95% confidence interval [CI]: 3.12-24.51%, P = 0.010) in the single-pollutant model. An increase of 10 μg/m³ in NO₂ exposure was associated with a 23.30% increased risk for the acquisition of S. pneumoniae-induced pneumonia in children (95% CI: 2.02-49.02%; P = 0.031) according to the multi-pollutant model. The ER of NO₂ with regard to the daily number of S. pneumoniae isolates (1 μg/ml ≤ minimum inhibitory concentration (MIC) to penicillin ≤ 2 μg/ml) obtained from the respiratory tract specimens of children with pneumonia was 15.80% (95% CI: 2.02-31.45%; P = 0.024) in the single-pollutant model. According to the multi-pollutant model, the ER of NO₂ with regard to the daily number of S. pneumoniae isolates (1 μg/ml ≤ MIC to penicillin ≤ 2 μg/ml) obtained from the respiratory tract specimens of children with pneumonia was 37.09% (95% CI: 5.70-77.81%; P = 0.018). In conclusion, ambient NO₂ is associated with S. pneumoniae-induced pneumonia in children. More importantly, NO₂ exposure is associated with the increased MICs of penicillin against S. pneumoniae from children with pneumonia.

Ceftaroline Fosamil for Treatment of Pediatric Complicated Skin and Soft Tissue Infections and Community-Acquired Pneumonia

Community-acquired pneumonia (CAP)/community-acquired bacterial pneumonia (CABP) and complicated skin and soft tissue infection (cSSTI)/acute bacterial skin and skin structure infection (ABSSSI) represent major causes of morbidity and mortality in children. β-Lactams are the cornerstone of antibiotic treatment for many serious bacterial infections in children; however, most of these agents have no activity against methicillin-resistant Staphylococcus aureus (MRSA). Ceftaroline fosamil, a β-lactam with broad-spectrum in vitro activity against Gram-positive pathogens (including MRSA and multidrug-resistant Streptococcus pneumoniae) and common Gram-negative organisms, is approved in the European Union and the United States for children with CAP/CABP or cSSTI/ABSSSI. Ceftaroline fosamil has completed a pediatric investigation plan including safety, efficacy, and pharmacokinetic evaluations in patients with ages ranging from birth to 17 years. It has demonstrated similar clinical and microbiological efficacy to best available existing treatments in phase III-IV trials in patients aged ≥ 2 months to < 18 years with CABP or ABSSSI, with a safety profile consistent with the cephalosporin class. It is also approved in the European Union for neonates with CAP or cSSTI, and in the US for neonates with ABSSSI. Ceftaroline fosamil dosing for children (including renal function adjustments) is supported by pharmacokinetic/pharmacodynamic modeling and simulations in appropriate age groups, and includes the option of 5- to 60-min intravenous infusions for standard doses, and a high dose for cSSTI patients with MRSA isolates, with a ceftaroline minimum inhibitory concentration of 2-4 mg/L. Considered together, these data suggest ceftaroline fosamil may be beneficial in the management of CAP/CABP and cSSTI/ABSSSI in children.

Limited generalizability of deep learning algorithm for pediatric pneumonia classification on external data

Purpose

(1) Develop a deep learning system (DLS) to identify pneumonia in pediatric chest radiographs, and (2) evaluate its generalizability by comparing its performance on internal versus external test datasets.

Methods

Radiographs of patients between 1 and 5 years old from the Guangzhou Women and Children’s Medical Center (Guangzhou dataset) and NIH ChestXray14 dataset were included. We utilized 5232 radiographs from the Guangzhou dataset to train a ResNet-50 deep convolutional neural network (DCNN) to identify pediatric pneumonia. DCNN testing was performed on a holdout set of 624 radiographs from the Guangzhou dataset (internal test set) and 383 radiographs from the NIH ChestXray14 dataset (external test set). Receiver operating characteristic curves were generated, and area under the curve (AUC) was compared via DeLong parametric method. Colored heatmaps were generated using class activation mapping (CAM) to identify important image pixels for DCNN decision-making.

Results

The DCNN achieved AUC of 0.95 and 0.54 for identifying pneumonia on internal and external test sets, respectively (p < 0.0001). Heatmaps generated by the DCNN showed the algorithm focused on clinically relevant features for images from the internal test set, but not for images from the external test set.

Conclusion

Our model had high performance when tested on an internal dataset but significantly lower accuracy when tested on an external dataset. Likewise, marked differences existed in the clinical relevance of features highlighted by heatmaps generated from internal versus external datasets. This study underscores potential limitations in the generalizability of such DLS models.

Clinical characteristics of children with airway malacia complicated by pneumonia

Background

Airway malacia is an important cause of noisy breathing, recurrent wheezing and respiratory infections, chronic coughing, and episodes of respiratory distress in young children. As the clinical manifestations of airway malacia are not common, many clinicians have insufficient understanding of this disease. So the purpose of this study is to summarize the pathogenic bacteria and clinical manifestations of airway softening complicated with pneumonia in children.

Methods

Children hospitalized with airway malacia complicated by pneumonia were eligible for enrollment from January 1, 2013 to December 31, 2019. Medical records of patients were reviewed for etiology, clinical characteristics, and laboratory examination results.

Results

A total of 164 pneumonia patients with airway malacia were admitted. The male-to-female ratio was 3:1. The age of patients ranged from 1 month to 4 years old. The median age was 6 (3–10) months. The most commonly detected pathogen were Mycoplasma pneumoniae (25/164, 15.24%), Streptococcus pneumoniae (18/164, 10.98%), and respiratory syncytial virus (16/164, 9.76%). Common signs among the 164 patients with confirmed airway malacia included cough (98.78%), wheezing (67.07%), fever (35.37%), intercostal retractions (23.17%), dyspnea (10.98%), cyanosis (11.11%), and crackles (50%). Compared with those without airway malacia, the incidence of premature delivery and mechanical ventilation was higher, and the duration of symptoms before admission (median, 13.5 d) and hospital stay (median 10.0 d) were longer. Of the children with pneumonia, 11.59% of those with airway malacia required supplemental oxygen compared with 4.88% of those without airway malacia (p < 0.05).

Conclusion

The median age of children with airway malacia was 6 months. The most common pathogen in patients with airway malacia complicated by pneumonia was Mycoplasma pneumoniae. Patients with airway malacia complicated by pneumonia often presented with a longer disease course, more severe symptoms, and had delayed recovery.

Serum levels of SIRT3 and other inflammatory factors are associated with clinical outcomes and prognosis in severe community-acquired pneumonia in adults: A prospective study

The aim of this study was to investigate clinical significance of SIRT3 in severe community-acquired pneumonia (CAP) patients.This prospective observational research enrolled a total of 114 severe CAP patients who went to our hospital during January 2018 to December 2019. Serum SIRT3 and IL-1β, IL-6, and tumor necrosis factor (TNF)-α levels were determined using the enzyme-linked immunosorbent assay (ELISA) method. Demographic data, including age, sex, and body mass index (BMI), as well as clinical symptoms, SOFA and SMART-COP scores were collected. The routine blood test was conducted for all patients and white blood cell (WBC) amount, as well as serum levels of C-reactive protein (CRP), D-Dimer, and procalcitonin (PCT).Among all patients, 55 cases died during the study period. The serum levels of CRP, PCT, IL-1β, and IL-6, as well as SOFA and SMART-COP scores were markedly higher in deceased patients than in the survival patients. The expression of SIRT3 was significantly decreased in severe CAP patients compared with the healthy, especially in the deceased patients. SIRT3 levels were negatively correlated with levels of CRP, PCT, IL-1β, and IL-6. Patients with SIRT3 low expression showed remarkably higher expression of CRP, PCT, IL-1β, and IL-6, as well as high SMART-COP scores, higher 1-month mortality rate, and shorter survival. Only SIRT3 and IL-1β were independent risk factors for 1-month mortality in severe CAP patients.Lower serum SIRT3 level predicts poor clinical outcomes and prognosis in severe CAP patients.

Antibiotic Prescribing Patterns for Hospitalized children with Community-Acquired Pneumonia in a Secondary Care Center

BACKGROUND

Narrow-spectrum antibiotics are recommended as the first-line therapy for management of children hospitalized with community-acquired pneumonia (CAP). There are limited data evaluating the antibiotic prescription patterns for CAP in Saudi Arabia. The goal of this study to report on the antibiotic patterns in children hospitalized with CAP.

METHODS

A prospective cross-sectional study was conducted in children aged 1 month to 13 years who were hospitalized with a diagnosis of CAP at King Khalid Hospital in Majmaah, Saudi Arabia, between January 2019 and January 2020.

RESULTS

Data from 233 patients were collected. The majority of patients received amoxicillin clavulanate (57.9%), followed by ceftriaxone (30%), azithromycin (20.6%), cefuroxime (6%), ampicillin (2.1%), and piperacillin-tazobactam (2.1%). None of our patients were started on narrow-spectrum therapy. The younger age group (1-3 months) and patients with severe pneumonia were more likely to receive broad-spectrum cephalosporin and have a longer hospital stay (P = .000 and P = .002, respectively). However, the 4 months to 5 years age group was more likely to receive amoxicillin clavulanate (P = .001). Male gender was a significate risk factor for patients with severe pneumonia (P=.013) CONCLUSIONS: We demonstrated the inappropriate use of broad-spectrum therapy in children hospitalized with CAP. Further large multicenter studies are necessary to evaluate the patterns of antibiotic use and implement antimicrobial stewardship programs or quality-improvement projects to improve adherence to guidelines.

Assessment of nasopharyngeal Streptococcus pneumoniae colonization does not permit discrimination between Canadian children with viral and bacterial respiratory infection: a matched-cohort cross-sectional study

Background

Readily-available diagnostics do not reliably discriminate between viral and bacterial pediatric uncomplicated pneumonia, both of which are common. Some have suggested that assessment of pneumococcal carriage could be used to identify those children with bacterial pneumonia. The objective of this study was to determine if nasopharyngeal pneumococcal colonization patterns differed between children with definite viral disease, definite bacterial disease, and respiratory disease of indeterminate etiology.

Methods

Three groups of subjects were recruited: children with critical respiratory illness, previously healthy children with respiratory illness admitted to the ward, and previously healthy children diagnosed in the emergency department with non-severe pneumonia. Subjects were categorized as follows: a) viral infection syndrome (eg. bronchiolitis), b) bacterial infection syndrome (ie. pneumonia complicated by effusion/empyema), or c) ‘indeterminate’ pneumonia. Subjects’ nasopharyngeal swabs underwent quantitative PCR testing for S. pneumoniae. Associations between categorical variables were determined with Fisher’s exact, chi-square, or logistic regression, as appropriate. Associations between quantitative genomic load and categorical variables was determined by linear regression.

Results

There were 206 children in Group 1, 122 children in Group 2, and 179 children in Group 3. Only a minority (227/507, 45%) had detectable pneumococcal carriage; in those subjects, there was no association of quantitative genomic load with age, recruitment group, or disease category. In multivariate logistic regression, pneumococcal colonization > 3 log copies/mL was associated with younger age and recruitment group, but not with disease category.

Conclusions

The nasopharyngeal S. pneumoniae colonization patterns of subjects with definite viral infection were very similar to colonization patterns of those with definite bacterial infection or indeterminate pneumonia. Assessment and quantification of nasopharyngeal pneumococcal colonization does not therefore appear useful to discriminate between acute viral and bacterial respiratory disease; consequently, this diagnostic testing is unlikely to reliably determine which children with indeterminate pneumonia have a bacterial etiology and/or require antibiotic treatment.

Properties of Mucoid Serotype 3 Streptococcus pneumoniae From Children in China

Objective

To investigate the characteristics of hosts, antimicrobial susceptibility, and molecular epidemiology of mucoid serotype 3 Streptococcus pneumoniae (S. pneumoniae) isolated from children in China.

Method

S. pneumoniae isolates collected between January 2016 and December 2019 were analyzed. S. pneumoniae isolates with mucoid phenotype were selected visually, and serotype 3 isolates were confirmed by Quellung reaction. The antimicrobial susceptibility was measured by E-test. Multilocus sequence typing was used for clonal analysis.

Results

Twenty (3.04%) isolates of mucoid serotype 3 S. pneumoniae were identified from 657 clinical isolates, and all of them were noninvasive strains. The mean age of the hosts was 5.69 ± 3.28 years. The isolates included: 50.0% from the dissected tonsil or adenoid tissue in children with obstructive sleep apnea-hypopnea syndrome, 45.0% from sputum or bronchial lavages in children with pneumonia, and 5.0% from vaginal secretions of one patient with vulvovaginitis. All isolates were susceptible to penicillin, cefuroxime, ceftriaxone, meropenem, vancomycin, levofloxacin, trimethoprim/sulfamethoxazole, and rifampin but resistant to erythromycin. Sequence type (ST)505 and its clonal complex (CC) were the main genotypes (95%). Antimicrobial susceptibility of ST180 and ST505 were compared, and the minimum inhibitory concentration (MIC) of ST505 isolates was significantly higher than that of ST180 for tetracycline, trimethoprim/sulfamethoxazole, and meropenem.

Conclusions

Mucoid serotype 3 Streptococcus pneumoniae can be isolated from various body parts, among which the respiratory system is the most common. It can cause noninvasive infection in children, and it has high susceptibility to a variety of antibiotics, especially β-lactams, but is resistant to macrolides. CC505 is the novel clonal complex found in China, which may be related to the worldwide mainstream clonal complex (CC180) but has its own biological characteristics.

Natural Language Processing and Machine Learning to Enable Clinical Decision Support for Treatment of Pediatric Pneumonia

Pneumonia is the most frequent cause of infectious disease-related deaths in children worldwide. Clinical decision support (CDS) applications can guide appropriate treatment, but the system must first recognize the appropriate diagnosis. To enable CDS for pediatric pneumonia, we developed an algorithm integrating natural language processing (NLP) and random forest classifiers to identify potential pediatric pneumonia from radiology reports. We deployed the algorithm in the EHR of a large children's hospital using real-time NLP. We describe the development and deployment of the algorithm, and evaluate our approach using 9-months of data gathered while the system was in use. Our model, trained on individual radiology reports, had an AUC of 0.954. The intervention, evaluated on patient encounters that could include multiple radiology reports, achieved a sensitivity, specificity, and positive predictive value of0.899, 0.949, and 0.781, respectively.

Acute kidney injury in children hospitalized for community acquired pneumonia

BACKGROUND

Acute kidney injury (AKI) enhances the risk of later chronic kidney disease. Significant prevalence of AKI is reported in adults with community acquired pneumonia (CAP). We investigated prevalence of and prognostic factors for AKI in children hospitalized for CAP.

METHODS

We retrospectively collected clinical and biochemical data of 186 children (48.4% male; mean age 2.6±2.4 years) hospitalized for X-ray-confirmed CAP. AKI was defined according to Kidney Disease/Improving Global Outcomes creatinine criteria. We considered as basal serum creatinine the value estimated with Hoste (age) equation assuming basal eGFR were median age-based eGFR normative values for children ≤ 2 years of age and eGFR= 120 mL/min/1.73m² for children > 2 years. Univariate and multivariate logistic regression models were used to explore associations with AKI.

RESULTS

AKI was found in 38/186 (20.4%) patients. No patient required hemodialysis nor reached AKI stage 3, 5 (2.7%) reached AKI stage 2, and 33 (17.7%) AKI stage 1. Mean length of stay was 6.0±1.7, 6.9±2.3, and 12.2±1.5 days, for patients without AKI, stage 1 AKI, and stage 2 AKI (p < 0.001), respectively. Duration of symptoms before hospitalization (OR 1.2; 95%CI 1.09-1.43; p = 0.001), severe pneumonia (OR 11.9; 95%CI 4.3-33.3; p < 0.001), and serum C-reactive protein levels (OR 1.1; 95%CI 1.04-1.23; p = 0.004) were independent AKI predictors.

CONCLUSIONS

About 1/5 of children hospitalized for CAP present a generally mild AKI with a longer stay for those with more severe AKI. Attention should be paid to kidney health of children with CAP especially in presence of higher duration of symptoms before hospitalization, severe pneumonia and higher serum CRP levels.

Age-Specific Differences in the Severity of COVID-19 Between Children and Adults: Reality and Reasons

In severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, children experience mild symptoms compared to adults. However, the precise explanations for this disparity are not clear. Thus, we attempted to identify rational explanations about age-related differences as reported in different studies. Given the incomplete data on SARS-CoV-2, some information has been gathered from other studies of earlier coronavirus or influenza outbreaks. Age-related differences in disease severity are important with regard to diagnosis, prognosis, and treatment of SARS-CoV-2 infections. In addition, these differences impact social distancing needs, since pediatric patients with mild or asymptomatic are likely to play a significant role in disease transmission.

International Survey on Determinants of Antibiotic Duration and Discontinuation in Pediatric Critically Ill Patients

OBJECTIVES

We hypothesized that antibiotic use in PICUs is based on criteria not always supported by evidence. We aimed to describe determinants of empiric antibiotic use in PICUs in eight different countries.

DESIGN

Cross-sectional survey.

SETTING

PICUs in Canada, the United States, France, Italy, Saudi Arabia, Japan, Thailand, and Brazil.

SUBJECTS

Pediatric intensivists.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We used literature review and focus groups to develop the survey and its clinical scenarios (pneumonia, septic shock, meningitis, and intra-abdominal infections) in which cultures were unreliable due to antibiotic pretreatment. Data analyses included descriptive statistics and linear regression with bootstrapped SEs. Overall response rate was 39% (482/1,251), with individual country response rates ranging from 25% to 76%. Respondents in all countries prolonged antibiotic duration based on patient characteristics, disease severity, pathogens, and radiologic findings (from a median increase of 1.8 d [95% CI, 0.5-4.0 d] to 9.5 d [95% CI, 8.5-10.5 d]). Younger age, severe disease, and ventilator-associated pneumonia prolonged antibiotic treatment duration despite a lack of evidence for such practices. No variables were reported to shorten treatment duration for all countries. Importantly, more than 39% of respondents would use greater than or equal to 7 days of antibiotics for patients with a positive viral polymerase chain reaction test in all scenarios, except in France for pneumonia (29%), septic shock (13%), and meningitis (6%). The use of elevated levels of inflammatory markers to prolong antibiotic treatment duration varied among different countries.

CONCLUSIONS

Antibiotic-related decisions are complex and may be influenced by cultural and contextual factors. Evidence-based criteria are necessary to guide antibiotic duration and ensure the rational use of antibiotics in PICUs.

Community-acquired pneumonia among children: the latest evidence for an updated management

OBJECTIVE

To provide cutting-edge information for the management of community-acquired pneumonia in children under 5 years, based on the latest evidence published in the literature.

DATA SOURCE

A comprehensive search was conducted in PubMed, by using the expressions: "community-acquired pneumonia" AND "child" AND "etiology" OR "diagnosis" OR "severity" OR "antibiotic". All articles retrieved had the title and the abstract read, when the papers reporting the latest evidence on each subject were identified and downloaded for complete reading.

DATA SYNTHESIS

In the era of largely implemented bacterial conjugate vaccines and widespread use of amplification nucleic acid techniques, respiratory viruses have been identified as the most frequent causative agents of community-acquired pneumonia in patients under 5 years. Hypoxemia (oxygen saturation ≤96%) and increased work of breathing are signs most associated with community-acquired pneumonia. Wheezing detected on physical examination independently predicts viral infection and the negative predictive value (95% confidence interval) of normal chest X-ray and serum procalcitonin <0.25ng/dL was 92% (77-98%) and 93% (90-99%), respectively. Inability to drink/feed, vomiting everything, convulsions, lower chest indrawing, central cyanosis, lethargy, nasal flaring, grunting, head nodding, and oxygen saturation <90% are predictors of death and can be used as indicators for hospitalization. Moderate/large pleural effusions and multilobar infiltrates are predictors of severe disease. Orally administered amoxicillin is the first line outpatient treatment, while ampicillin, aqueous penicillin G, or amoxicillin (initiated initially by intravenous route) are the first line options to treat inpatients.

CONCLUSIONS

Distinct aspects of childhood community-acquired pneumonia have changed during the last three decades.

Community‐acquired pneumonia among children: the latest evidence for an updated management

Objetivo

Fonte de dados

Síntese dos dados

Conclusões

Blood biomarkers differentiating viral versus bacterial pneumonia aetiology: a literature review

Background and objectives

The goal of this literature review is to compare current studies regarding the accuracy of different serum markers in differentiating viral from bacterial pneumonia in the pediatric population with what is employed in the medical settings at present. Currently there is still a lack of significant research, that would give us evaluation on biomarkers benefits towards getting a definite diagnosis of pneumonia. Finding out the potential of biomarkers to differentiate between viral and bacterial pneumonia is also important because knowing the exact pathogen would prevent irrational use of antibiotics. At present, irrational, broad-spectrum antibiotic use and increasing antibiotic resistance in microorganisms are still one of the greatest challenges in clinical settings. The use of biomarkers in clinical practice would not only facilitate accurate diagnosis, but would also help to reduce the amount of antibiotics overuse.

Materials and methods

Literature search conducted on Medline and Google Scholar using a combination of terms. Articles that were in English and within ten years of the search date were manually sorted according to inclusion and exclusion criteria. Results: Initial search returned n = 13,408. After activating filters, n = 140 were identified of which n = 12 included for literature review.

Conclusions

Rise or drop in the concentration of a single marker is not accurate enough for predicting viral/bacterial community acquired pneumonia. This is because there is overlapping to a varying extent depending on the marker cut-off values, detection methods, analyses, the desired specificity, and sensitivity. Furthermore, the presence of mixed infection makes almost all markers suboptimal to be used universally. New markers such as MxA1 and HMGB1 gave promising results. However, to replicate a similar testing condition in a clinical environment may not be practical. Another approach is to make use of more than one marker and combine with clinical signs and symptoms. This may not be cost-effective in many clinical settings; nevertheless, in many studies, marker combination greatly improved the predictive power.

Improving antibiotic prescribing in the emergency department for uncomplicated community-acquired pneumonia

BACKGROUND

The Pediatric Infectious Disease Society (PIDS) and Infectious Disease Society of America (IDSA) published an evidence-based guideline for the treatment of uncomplicated community-acquired pneumonia (CAP) in children, recommending aminopenicillins as the first-line therapy. Poor guideline compliance with 10%-50% of patients admitted to the hospital receiving narrow-spectrum antibiotics has been reported. A new clinical practice guideline (CPG) was implemented in our emergency department (ED) for uncomplicated CAP. The aim of this study was to examine baseline knowledge and ED provider prescribing patterns pre- and post-CPG implementation.

METHODS

Prior to CPG-implementation, an anonymous case-based survey was distributed to evaluate knowledge of the current PIDS/IDSA guideline. A retrospective chart review of patients treated in the ED for CAP from January 2015 to February 2017 was performed to assess prescribing patterns for intravenous (IV) antibiotics in the ED at Children's National Health System pre- and post-CPG implementation.

RESULTS

ED providers were aware of the PIDS/IDSA guideline recommendations, with 86.4% of survey responders selecting ampicillin as the initial antibiotic of choice. However, only 41.2% of patients admitted to the hospital with uncomplicated CAP pre-CPG received ampicillin (P<0.01). There was no statistically significant increase in ampicillin prescribing post-CPG (P=0.40).

CONCLUSIONS

Providers in the ED are aware of the PIDS/IDSA guideline regarding the first-line therapy for uncomplicated CAP; however, this knowledge does not translate into clinical practice. Implementation of a CPG in isolation did not significantly change prescribing patterns for uncomplicated CAP.

Evolution of cytokines/chemokines in cases with community-acquired pneumonia and distinct etiologies

AIM

To compare the systemic cytokines/chemokines levels over time during the evolution of children hospitalized with community-acquired pneumonia (CAP) with and without pneumococcal infection.

METHODS

Children less than 5-years-old hospitalized with CAP were prospectively investigated in Salvador, Brazil. Clinical data and biological samples were collected to investigate 20 etiological agents and to determine serum cytokines/chemokines levels on admission and 2 to 4 weeks later. Cases with pneumococcal infection received this diagnosis irrespective of also having other etiologies.

RESULTS

A total of 277 patients were enrolled, however, serum sample was unavailable for cytokine measurement upon admission (n = 61) or upon follow-up visit (n = 36), etiology was undetected (n = 50) and one patient did not attend the follow-up visit. Therefore, this study group comprised of 129 cases with established etiology. The median (interquartile range) age and sampling interval was 18 (9-27) months and 18 (16-21) days, respectively. Established etiology was viral (52.0%), viral-bacterial (30.2%), and bacterial (17.8%). Pneumococcal infection was found in 31 (24.0%) patients. Overall, median interleukin-6 (IL-6; 10.6 [4.7-30.6] vs 21.0 [20.2-21.7]; P = .03), IL-10 (3.5 [3.1-4.5] vs 20.1 [19.8-20.4]; P < .001), and CCL2 (19.3 [12.4-23.2] vs 94.0 [67.2-117.8]; P < .001) were significantly higher in convalescent serum samples, whereas median CXCL10 (83.6 [36.4-182.9] vs 14.6 [0-116.6]; P < .001) was lower. Acute vs convalescent levels evolution of IL-10, CCL2, and CXCL10 did not differ among patients with or without pneumococcal infection. However, IL-6 decreased (27.8 [12.3-48.6] vs 20.8 [20.2-22.6]; P = .1) in patients with pneumococcal infection and increased (9.0 [4.2-22.6] vs 21.0 [20.2-21.7]; P = .001) in patients without it.

CONCLUSION

The marked increase of IL-6 serum levels during the acute phase makes it a potential biomarker of pneumococcal infection among children with CAP.

Outcome of Severe Bacterial Pneumonia in the Era of Pneumococcal Vaccination

Introduction: After the introduction of pneumococcal conjugate vaccines, community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae has decreased whereas Staphylococcus aureus and Streptococcus pyogenes could be increasing. These bacteria have been associated with high rates of complications. Aims: (1) To describe the characteristics of pediatric bacterial CAP requiring hospitalization. (2) To compare outcomes according to causative microorganisms. (3) To analyze changes in bacterial CAP rate and etiology over time. Patients and Methods: Retrospective single-center study of inpatients aged 1 month-16 years with culture-confirmed bacterial CAP in 2010-2018 in Madrid, Spain. Results: We included 64 cases (42 S. pneumoniae, 13 S. pyogenes and 9 S. aureus). Culture-confirmed CAP represented 1.48-2.33/1,000 all-cause pediatric hospital admissions, and its rate did not vary over time. However, there was a significant decrease in pneumococcal CAP in the last 3 years of the study (78% of CAP in 2010-2015 vs. 48% in 2016-18, p = 0.017). Median hospital stay was 10.5 days (interquartile range 5-19.5), 38 patients (59%) developed complications and 28 (44%) were admitted to the intensive care unit. Outcomes were similar among children with S. pneumoniae and S. aureus CAP, whereas S. pyogenes was associated with a higher risk for complications (OR 8 [95%CI 1.1-57.2]) and ICU admission (OR 7.1 [95%CI 1.7-29.1]) compared with pneumococcal CAP. Conclusion: In a setting with high PCV coverage, culture-confirmed bacterial CAP did not decrease over time and there was a relative increase of S. pyogenes and S. aureus. Children with CAP caused by S. pyogenes were more likely to develop complications.

Host-Pathogen Interactions in Gram-Positive Bacterial Pneumonia

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide. Despite broad literature including basic and translational scientific studies, many gaps in our understanding of host-pathogen interactions remain. In this review, pathogen virulence factors that drive lung infection and injury are discussed in relation to their associated host immune pathways. CAP epidemiology is considered, with a focus on Staphylococcus aureus and Streptococcus pneumoniae as primary pathogens. Bacterial factors involved in nasal colonization and subsequent virulence are illuminated. A particular emphasis is placed on bacterial pore-forming toxins, host cell death, and inflammasome activation. Identified host-pathogen interactions are then examined by linking pathogen factors to aberrant host response pathways in the context of acute lung injury in both primary and secondary infection. While much is known regarding bacterial virulence and host immune responses, CAP management is still limited to mostly supportive care. It is likely that improvements in therapy will be derived from combinatorial targeting of both pathogen virulence factors and host immunomodulation.