Perinatal exposure to traffic related air pollutants and the risk of infection in the first six months of life: a cohort study from a low-middle income country

OBJECTIVE

There is limited study from low-and-middle income countries on the effect of perinatal exposure to air pollution and the risk of infection in infant. We assessed the association between perinatal exposure to traffic related air pollution and the risk of infection in infant during their first six months of life.

METHODS

A prospective cohort study was performed in Jakarta, March 2016-September 2020 among 298 mother-infant pairs. PM2.5, soot, NOx, and NO2 concentrations were assessed using land use regression models (LUR) at individual level. Repeated interviewer-administered questionnaires were used to obtain data on infection at 1, 2, 4 and 6 months of age. The infections were categorized as upper respiratory tract (runny nose, cough, wheezing or shortness of breath), lower respiratory tract (pneumonia, bronchiolitis) or gastrointestinal tract infection. Logistic regression models adjusted for covariates were used to assess the association between perinatal exposure to air pollution and the risk of infection in the first six months of life.

RESULTS

The average concentrations of PM2.5 and NO2 were much higher than the WHO recommended levels. Upper respiratory tract infections (URTI) were much more common in the first six months of life than diagnosed lower respiratory tract or gastro-intestinal infections (35.6%, 3.5% and 5.8% respectively). Perinatal exposure to PM2.5 and soot suggested increase cumulative risk of upper respiratory tract infection (URTI) in the first 6 months of life per IQR increase with adjusted OR of 1.50 (95% CI 0.91; 2.47) and 1.14 (95% CI 0.79; 1.64), respectively. Soot was significantly associated with the risk of URTI at 4-6 months age interval (aOR of 1.45, 95%CI 1.02; 2.09). All air pollutants were also positively associated with lower respiratory tract infection, but all CIs include unity because of relatively small samples. Adjusted odds ratios for gastrointestinal infections were close to unity.

CONCLUSION

Our study adds to the evidence that perinatal exposure to fine particles is associated with respiratory tract infection in infants in a low-middle income country.

Utilizing metagenomic next-generation sequencing for pathogen detection and diagnosis in lower respiratory tract infections in real-world clinical practice

BACKGROUND

Infectious etiologies of lower respiratory tract infections (LRTIs) by the conventional microbiology tests (CMTs) can be challenging. Metagenomic next-generation sequencing (mNGS) has great potential in clinical use for its comprehensiveness in identifying pathogens, particularly those difficult-to-culture organisms.

METHODS

We analyzed a total of 205 clinical samples from 201 patients with suspected LRTIs using mNGS in parallel with CMTs. mNGS results were used to guide treatment adjustments for patients who had negative CMT results. The efficacy of treatment was subsequently evaluated in these patients.

RESULTS

mNGS-detected microorganisms in 91.7% (188/205) of the clinical samples, whereas CMTs demonstrated a lower detection rate, identifying microorganisms in only 37.6% (77/205) of samples. Compared to CMT results, mNGS exhibited a detection sensitivity of 93.5% and 95.4% in all 205 clinical samples and 180 bronchoalveolar lavage fluid (BALF) samples, respectively. A total of 114 patients (114/201; 56.7%) showed negative CMT results, among which 92 received treatment adjustments guided by their positive mNGS results. Notably, 67.4% (62/92) of patients demonstrated effective treatment, while 25% (23/92) experienced a stabilized condition. Subgroup analysis of cancer patients revealed that 41.9% (13/31) exhibited an effective response to treatment, and 35.5% (11/31) maintained a stable condition following medication adjustments guided by mNGS.

CONCLUSION

mNGS demonstrated great potential in identifying microorganisms of clinical significance in LRTIs. The rapid turnaround time and reduced susceptibility to the impact of antimicrobial administration make mNGS a valuable supplementary tool for diagnosis and treatment decision-making for suspected LRTIs in clinical practice.

Assessment and clinical utility of metagenomic next-generation sequencing for suspected lower respiratory tract infections

OBJECTIVES

This study aims to compare the diagnostic efficacy of metagenomic next-generation sequencing (mNGS) to traditional diagnostic methods in patients with lower respiratory tract infections (LRTIs), elucidate the etiological spectrum of these infections, and explore the impact of mNGS on guiding antimicrobial therapy.

METHODS

We retrospectively analyzed data from 128 patients admitted to the Respiratory Department of Anqing 116 Hospital between July 2022 and July 2023. All patients had undergone both mNGS and conventional microbiological techniques (CMT) for LRTI diagnosis. We assessed the diagnostic performance of these methods and examined the influence of mNGS on antimicrobial decision-making.

RESULTS

Overall, mNGS demonstrated superior sensitivity (96.8%) and accuracy (96.8%) compared to CMT. For Mycobacterium tuberculosis detection, the accuracy and sensitivity of mNGS was 88.8% and 77.6%, which was lower than the 94.7% sensitivity of the T-spot test and the 79.6% sensitivity of CMT. In fungal pathogen detection, mNGS showed excellent sensitivity (90.5%), specificity (86.7%), and accuracy (88.0%). Bacteria were the predominant pathogens detected (75.34%), with Mycobacterium tuberculosis (41.74%), Streptococcus pneumoniae (21.74%), and Haemophilus influenzae (16.52%) being most prevalent. Bacterial infections were most common (62.10%), followed by fungal and mixed infections (17.74%). Of the 118 patients whose treatment regimens were adjusted based on mNGS results, 102 (86.5%) improved, 7 (5.9%) did not respond favorably, and follow-up was lost for 9 patients (7.6%).

CONCLUSIONS

mNGS offers rapid and precise pathogen detection for patients with suspected LRTIs and shows considerable promise in diagnosing Mycobacterium tuberculosis and fungal infections. By broadening the pathogen spectrum and identifying polymicrobial infections, mNGS can significantly inform and refine antibiotic therapy.

Challenges for a broad international implementation of the current severe community-acquired pneumonia guidelines

Severe community-acquired pneumonia (sCAP) remains one of the leading causes of admission to the intensive care unit, thus consuming a large share of resources and is associated with high mortality rates worldwide. The evidence generated by clinical studies in the last decade was translated into recommendations according to the first published guidelines focusing on severe community-acquired pneumonia. Despite the advances proposed by the present guidelines, several challenges preclude the prompt implementation of these diagnostic and therapeutic measures. The present article discusses the challenges for the broad implementation of the sCAP guidelines and proposes solutions when applicable.

Best Practices for Identifying Hospitalized Lower Respiratory Tract Infections Using Administrative Data: A Systematic Literature Review of Validation Studies

INTRODUCTION

Estimating the burden of lower respiratory tract infections (LRTIs) increasingly relies on administrative databases using International Classification of Diseases (ICD) codes, but no standard methodology exists. We defined best practices for ICD-based algorithms that estimate LRTI incidence in adults.

METHODS

We conducted a systematic review of validation studies assessing the use of ICD code-based algorithms to identify hospitalized LRTIs in adults, published in Medline, EMBASE, and LILACS between January 1996 and January 2022, according to PRISMA guidelines. We assessed sensitivity, specificity, and other accuracy measures of different algorithms.

RESULTS

We included 26 publications that used a variety of ICD code-based algorithms and gold standard criteria, and 18 reported sensitivity and/or specificity. Sensitivity was below 80% in 72% (38/53) of algorithms and specificity exceeded 90% in 77% (37/48). Algorithms for all-cause LRTI (n = 18) that included only pneumonia codes in primary position (n = 3) had specificity greater than 90% but low sensitivity (55-72%). Sensitivity increased by 5-15%, with minimal loss in specificity, with the addition of primary codes for severe pneumonia (e.g. sepsis) while pneumonia codes were in secondary position, and by 13% with codes from LRTI-related infections (e.g. viral) or other respiratory diseases (e.g. empyema). Sensitivity increased by 8% when pneumonia codes were in any position, but specificity was not reported. In hospital-acquired pneumonia and pneumococcal-specific pneumonia, algorithms containing only nosocomial- or pathogen-specific ICD codes had poor sensitivity, which improved when broader pneumonia codes were added, in particular codes for unspecified organisms.

CONCLUSION

Our systematic review highlights that most ICD code-based algorithms are relatively specific, but miss a substantial number of hospitalized LRTI adult cases. Best practices to estimate LRTI incidence in this population include the use of all pneumonia ICD codes for any LRTI outcome and, to a lesser extent, those for other LRTI-related infections or respiratory diseases.

Determinants of radiological patterns and severity in immunocompromised adults with Metapneumovirus infection

BACKGROUND

Human Metapneumovirus (HMPV) belongs to the Pneumoviridae family and is responsible for respiratory infections. Mild infections are well-recognized in children, while its precise impact in various categories of immunocompromised adults has not been well addressed.

RESEARCH QUESTION

We retrospectively studied HMPV infections in immunocompromised adults followed in two large French university medical centers.

STUDY DESIGN AND METHODS

We identified immunocompromised adults with positive HMPV Polymerase Chain Reaction (PCR) for 36 months and reviewed their medical charts. For lung transplant recipients (LTR), FEV1 was collected at baseline, during and after infection. Imaging was centralized and chest involvement was categorized by dominant CT patterns. We compared severe patients (requiring oxygen or ventilation) and non hypoxemic patients.

RESULTS

Seventy-two patients were included, 27 were LTR, 25 had a hematological malignancy or were hematopoietic stem cell recipients, 20 had another immunocompromised status. Twenty patients (28%) presented a hypoxemic infection, requiring hospitalization and intensive care units transfers in 50/72 (69.4%) and 9/72 (12.5%) respectively, with only one death. Hypoxemia was less pronounced in LTRs (p = 0.014). Finally, age and dyspnea remained independent factors associated with hypoxemia (p < 0.005). The most frequent radiological patterns were bronchopneumonia (34.2%) and bronchiolitis (39.5% and 64.3% in the overall population and in LTRs respectively, p = 0.045). FEV1 improved in LTRs at one month and 85% had recovered their baseline FEV1 within 6 months.

INTERPRETATIONS

In immunocompromised adults, HMPV infections required frequent hospitalizations and ICU transfers, while mortality is low. In LTRs, bronchiolitis pattern was predominant with short and long-term favorable outcome.

Empagliflozin and risk of lower respiratory tract infection in heart failure with mildly reduced and preserved ejection fraction: An EMPEROR-Preserved analysis

AIMS

Lower respiratory tract infections (LRTI) are common worldwide. Patients with heart failure and mildly reduced or preserved ejection fraction (HFmrEF/HFpEF) have a high risk of developing LRTI. Prior studies were able to show that sodium-glucose cotransporter 2 inhibitors may reduce the incidence of LRTI in patients with type 2 diabetes. The aim of this study was to evaluate patient characteristics and prognosis according to LRTI status and to assess the effect of empagliflozin on LRTI in 5988 patients with HFmrEF/HFpEF enrolled in the EMPEROR-Preserved trial randomized to either empagliflozin or placebo over a median follow-up of 26 months.

METHODS AND RESULTS

Time-updated models were used to study the mortality risk after a LRTI. Cox regression was used to study the effect of empagliflozin on incident LRTI. Throughout the follow-up, 699 of 5988 (11.7%) patients developed LRTI: these were older, were more frequently hospitalized within the previous year, had type 2 diabetes, chronic kidney disease, and had higher N-terminal pro-B-type natriuretic peptide levels than patients without incident LRTI. Patients who developed LRTI had a 2.7-fold higher risk of subsequent mortality compared to patients without LRTI. The incidence of LRTI was 5.2 (95% confidence interval [CI] 4.6-5.8) events per 100 person-years in the empagliflozin group and 6.2 (95% CI 5.6-6.9) events per 100 person-years in the placebo group (hazard ratio 0.83, 95% CI 0.71-0.96, p = 0.014). The total number of LRTI events was reduced in the empagliflozin group (incidence rate ratio 0.80, 95% CI 0.68-0.94, p = 0.008). No effect of empagliflozin was observed on COVID-19 incidence.

CONCLUSION

In EMPEROR-Preserved, LRTI was frequent and associated with a poor prognosis. Empagliflozin was associated with a reduced risk of LRTI compared to placebo.

Costs and healthcare utilisation due to respiratory syncytial virus disease in paediatric patients in Italy: a systematic review

OBJECTIVES

Respiratory syncytial virus (RSV) is a frequent cause of acute lower respiratory infection in children, imposing a substantial economic burden on healthcare systems. This systematic review aimed to assess the economic burden and healthcare utilisation of RSV in children aged 0-59 months in Italy.

STUDY DESIGN

Systematic review.

METHODS

A systematic search of PubMed, Embase, Scopus, and the International HTA Database, including studies published in English or Italian, was conducted between January 2000 and July 2022. Inclusion criteria required studies to be conducted in Italy and provide data on the economic costs and healthcare resource utilisation related to RSV infections.

RESULTS

Out of 20,845 records screened, 18 articles met the inclusion criteria. Only one study provided comprehensive data on RSV disease costs, including hospitalisation, diagnostic tests, and medical procedures for infants with RSV-bronchiolitis. The mean cost per inpatient was higher for RSV-positive children (€5753.43 ± €2041.62) than that for RSV-negative children. Additionally, five studies reported a median length of hospital stay of 5 days for RSV-infected children, and four studies indicated a higher frequency of intensive care unit admissions for RSV-infected children than for those with other viral infections.

CONCLUSIONS

This is the first systematic review to examine the economic burden and healthcare utilisation of RSV in children aged 0-59 months in Italy. While limited data were available, the findings underscore the urgency to conduct further research and gather additional evidence on the costs and healthcare resource utilisation associated with RSV infections. Such efforts are essential for informing the development of effective prevention strategies for paediatric RSV infections in Italy.

Assessment of antibacterial drug utilization patterns and antibiogram in infectious diseases: a prospective cross-sectional study

BACKGROUND

Antibacterial drugs are successful in combating most types of infections. Irrational use and higher consumption of these drugs can give rise to the antibiotic resistance globally.

OBJECTIVE

To evaluate antibacterial drug prescribing patterns and antibiogram in infectious disease cases admitted to the hospital.

METHODS

A cross-sectional, observational study was conducted from September 2019 to February 2020 among inpatients ward at the hospital after ethical approval. All the data was analysed by the mean and percentage values using Microsoft excel.

RESULTS

Out of 250 admitted patients, males and females were 156 (62%) and 94 (38%) respectively. The majority of patients 79 (32%) belonged to the age group of 20-40 years. The majority of prescriptions reported were for viral fever 48 (19%), lower respiratory tract infections 40 (16%) and dengue 33 (13%). Antibacterial drugs administered through the intravenous route and the oral route were 301 (83%) and 63 (17%) respectively. The most frequently utilized antibacterial drugs were beta-lactam class ceftriaxone 149 (60%) and the fixed-dose combination, amoxicillin plus clavulanic acid 65 (26%). Further highly prescribed antibacterial drugs were metronidazole 52 (21%), azithromycin 36 (15%), and levofloxacin 24 (10%). In Gram-negative bacteria, Escherichia coli 6 (30%) contributed majorly, while in Gram-positive coagulase-negative, Staphylococci 6 (30%) contributed the highest growth of bacteria for the specific infections in the admitted cases.

CONCLUSION

Ceftriaxone and the amoxicillin-clavulanic acid combination were highly prescribed among all antibacterial drugs, followed by metronidazole and azithromycin. The current study showed that in the antibiogram pattern, Escherichia coli and coagulase-negative Staphylococci contributed significantly as causative organisms for infectious disease cases. The present study highlighted demographic distribution, infectious diseases with their antibacterial drug utilization patterns and antibiogram assessment in the admitted patients.

Incomplete and possibly selective recording of signs, symptoms, and measurements in free text fields of primary care electronic health records of adults with lower respiratory tract infections

OBJECTIVES

To assess the completeness of recording of relevant signs, symptoms, and measurements in Dutch free text fields of primary care electronic health records (EHR) of adults with lower respiratory tract infections (LRTI).

STUDY DESIGN AND SETTING

Retrospective cohort study embedded in a prediction modeling project using routine health care data of the Julius General Practitioners' Network of adult patients with LRTI. Free text fields of 1,000 primary care consultations of LRTI episodes between 2016 and 2019 were manually annotated to retrieve data on the recording of sixteen relevant signs, symptoms, and measurements.

RESULTS

For 12/16 (75%) of the relevant signs, symptoms, and measurements, more than 50% of the values was not recorded. The patterns of recorded values indicated selective recording of positive or abnormal values. Recording rates varied across consultation type (physical consultation vs. home visit), diagnosis (acute bronchitis vs. pneumonia), antibiotic prescription issued (yes vs. no), and between practices.

CONCLUSION

In EHR of primary care LRTI patients, recording of signs, symptoms, and measurements in free text fields is incomplete and possibly selective. When using free text data in EHR-based research, careful consideration of its recording patterns and appropriate missing data handling techniques is therefore required.

PLUS-IS-LESS project: Procalcitonin and Lung UltraSonography-based antibiotherapy in patients with Lower rESpiratory tract infection in Swiss Emergency Departments: study protocol for a pragmatic stepped-wedge cluster-randomized trial

BACKGROUND

Lower respiratory tract infections (LRTIs) are among the most frequent infections and a significant contributor to inappropriate antibiotic prescription. Currently, no single diagnostic tool can reliably identify bacterial pneumonia. We thus evaluate a multimodal approach based on a clinical score, lung ultrasound (LUS), and the inflammatory biomarker, procalcitonin (PCT) to guide prescription of antibiotics. LUS outperforms chest X-ray in the identification of pneumonia, while PCT is known to be elevated in bacterial and/or severe infections. We propose a trial to test their synergistic potential in reducing antibiotic prescription while preserving patient safety in emergency departments (ED).

METHODS

The PLUS-IS-LESS study is a pragmatic, stepped-wedge cluster-randomized, clinical trial conducted in 10 Swiss EDs. It assesses the PLUS algorithm, which combines a clinical prediction score, LUS, PCT, and a clinical severity score to guide antibiotics among adults with LRTIs, compared with usual care. The co-primary endpoints are the proportion of patients prescribed antibiotics and the proportion of patients with clinical failure by day 28. Secondary endpoints include measurement of change in quality of life, length of hospital stay, antibiotic-related side effects, barriers and facilitators to the implementation of the algorithm, cost-effectiveness of the intervention, and identification of patterns of pneumonia in LUS using machine learning.

DISCUSSION

The PLUS algorithm aims to optimize prescription of antibiotics through improved diagnostic performance and maximization of physician adherence, while ensuring safety. It is based on previously validated tests and does therefore not expose participants to unforeseeable risks. Cluster randomization prevents cross-contamination between study groups, as physicians are not exposed to the intervention during or before the control period. The stepped-wedge implementation of the intervention allows effect calculation from both between- and within-cluster comparisons, which enhances statistical power and allows smaller sample size than a parallel cluster design. Moreover, it enables the training of all centers for the intervention, simplifying implementation if the results prove successful. The PLUS algorithm has the potential to improve the identification of LRTIs that would benefit from antibiotics. When scaled, the expected reduction in the proportion of antibiotics prescribed has the potential to not only decrease side effects and costs but also mitigate antibiotic resistance.

TRIAL REGISTRATION

This study was registered on July 19, 2022, on the ClinicalTrials.gov registry using reference number: NCT05463406.

TRIAL STATUS

Recruitment started on December 5, 2022, and will be completed on November 3, 2024. Current protocol version is version 3.0, dated April 3, 2023.

Severe viral lower respiratory tract infections in Brazilian children: Clinical features of a national cohort

BACKGROUND

The accurate etiological diagnosis of lower respiratory tract infections (LRTI) is essential for their effective clinical management. The extensive use of molecular methods during the COVID-19 pandemic has enabled massive data acquisition on viral lower respiratory tract infections. The current study aims to identify clinical features associated with eight viral agents among children presenting severe LRTI.

METHODS

retrospective cohort study of data from the Brazilian Influenza Epidemiological Surveillance Information System. Patients under 20 years-old who had severe LRTI with etiological confirmation through RT-PCR between 2020 and 2022 were included. Binary logistic regressions were used to examine associations between pathogens and symptoms.

RESULTS

60,657 cases were assessed. The main viral agents detected were Sars-CoV-2 (COV2) (41.2%), Respiratory Syncytial Virus (29.1%), Human Rhinovirus (HRV) (12.1%), and Influenza (FLU) (5.5%). A general mortality rate of 4.3% was observed. The multivariate analysis evidenced that COV2 less likely presented with cough (OR: 0.34; 95%CI: 0.32-0.36), respiratory discomfort (Adjusted Odds Ratio (aOR): 0.61; 95%Confidence Interval (CI): 0.59-0.64), and desaturation (aOR: 0.71; 95%CI: 0.69-0.75). RSV strongly associated with cough (aOR: 2.59; 95%CI: 2.45-2.75) and respiratory discomfort (aOR: 1.54; 95%CI: 1.46-1.62), whereas FLU was linked to fever (aOR: 2.27; 95%CI: 2.06-2.50) and sore throat (aOR: 1.48; 95%CI: 1.34-1.64).

CONCLUSIONS

The viral agents responsible for severe LRTI have distinct associations with clinical features in children.

Performance evaluation of the LumiraDx quantitative microfluidic point-of-care CRP test

C-reactive protein (CRP) is an established acute-phase marker for infection, inflammation and tissue injury, used to guide clinical decision-making in primary and secondary care. This study compared the analytical performance of the quantitative microfluidic point-of-care LumiraDx CRP Test to a laboratory-based reference method (Siemens RCRP Flex assay on the Dimension® Xpand®) and evaluated equivalence of sample matrices (blood versus plasma) in point-of-care settings using samples from patients presenting with symptoms of infection or inflammation. The LumiraDx CRP Test demonstrated close agreement with the lab reference test (range, 5.1 to 245.2 mg/L, r = 0.992, slope = 0.998, intercept = -0.476; n = 205) and notable agreement between fingerstick and venous blood and plasma (r = 0.974-0.983; n = 44). Paired replicate precision had mean coefficients of variation of 6.4 % (plasma), 6.6 % (capillary direct) and 8.1 % (venous blood); overall error rates were 2.9 %. The quantitative LumiraDx CRP Test showed robust analytical performance across sample matrices and close agreement compared to the laboratory reference method when used at the point of care.

Predicting adverse outcomes in adults with a community-acquired lower respiratory tract infection: a protocol for the development and validation of two prediction models for (i) all-cause hospitalisation and mortality and (ii) cardiovascular outcomes

BACKGROUND

Community-acquired lower respiratory tract infections (LRTI) are common in primary care and patients at particular risk of adverse outcomes, e.g., hospitalisation and mortality, are challenging to identify. LRTIs are also linked to an increased incidence of cardiovascular diseases (CVD) following the initial infection, whereas concurrent CVD might negatively impact overall prognosis in LRTI patients. Accurate risk prediction of adverse outcomes in LRTI patients, while considering the interplay with CVD, can aid general practitioners (GP) in the clinical decision-making process, and may allow for early detection of deterioration. This paper therefore presents the design of the development and external validation of two models for predicting individual risk of all-cause hospitalisation or mortality (model 1) and short-term incidence of CVD (model 2) in adults presenting to primary care with LRTI.

METHODS

Both models will be developed using linked routine electronic health records (EHR) data from Dutch primary and secondary care, and the mortality registry. Adults aged ≥ 40 years with a GP-diagnosis of LRTI between 2016 and 2019 are eligible for inclusion. Relevant patient demographics, medical history, medication use, presenting signs and symptoms, and vital and laboratory measurements will be considered as candidate predictors. Outcomes of interest include 30-day all-cause hospitalisation or mortality (model 1) and 90-day CVD (model 2). Multivariable elastic net regression techniques will be used for model development. During the modelling process, the incremental predictive value of CVD for hospitalisation or all-cause mortality (model 1) will also be assessed. The models will be validated through internal-external cross-validation and external validation in an equivalent cohort of primary care LRTI patients.

DISCUSSION

Implementation of currently available prediction models for primary care LRTI patients is hampered by limited assessment of model performance. While considering the role of CVD in LRTI prognosis, we aim to develop and externally validate two models that predict clinically relevant outcomes to aid GPs in clinical decision-making. Challenges that we anticipate include the possibility of low event rates and common problems related to the use of EHR data, such as candidate predictor measurement and missingness, how best to retrieve information from free text fields, and potential misclassification of outcome events.

Risk of subsequent lower respiratory tract infection (LRTI) after hospitalization for COVID-19 LRTI and non-COVID-19 LRTI: a retrospective cohort study

BACKGROUND

Respiratory pathogens, including SARS-CoV-2, can cause pulmonary structural damage and physiologic impairment, which may increase the risk of subsequent lower respiratory tract infections (LRTI). Prior hospitalization for any reason is a risk factor for LRTI, but data on the risk of subsequent new-onset LRTI following hospitalization for COVID-19 LRTI or non-COVID-19 LRTI are needed to inform strategies for immunizations targeting respiratory pathogens.

METHODS

We conducted a retrospective cohort study at Kaiser Permanente Southern California (KPSC) among adults hospitalized from 3/1/2020 to 5/31/2022, excluding labor and delivery. We categorized individuals into 3 mutually exclusive baseline exposure groups: those hospitalized for COVID-19 LRTI, those hospitalized for non-COVID-19 LRTI, and those hospitalized for all other causes without LRTI or COVID-19 ("non-LRTI"). Following hospital discharge, patients were followed up for new-onset LRTI, beginning 30 antibiotic-free days after hospital discharge until 8/31/2022. We used multivariable cause-specific Cox regression with time-varying covariates to estimate hazard ratios (HR) of new-onset LRTI comparing those hospitalized for COVID-19 LRTI or non-COVID-19 LRTI to those hospitalized for non-LRTI, adjusting for demographic and clinical characteristics.

RESULTS

The study included 22,417 individuals hospitalized for COVID-19 LRTI, 12,795 individuals hospitalized for non-COVID-19 LRTI, and 176,788 individuals hospitalized for non-LRTI. Individuals hospitalized for non-COVID-19 LRTI were older and had more comorbidities than those hospitalized for COVID-19 LRTI or non-LRTI. Incidence rates per 1,000 person-years (95% CI) of new-onset LRTI were 52.5 (51.4-53.6) among individuals hospitalized for COVID-19 LRTI, 253.5 (243.7-263.6) among those hospitalized for non-COVID-19 LRTI, and 52.5 (51.4-53.6) among those hospitalized for non-LRTI. The adjusted hazard of new-onset LRTI during follow-up was 20% higher among individuals hospitalized for COVID-19 LRTI (HR 1.20 [95% CI: 1.12-1.28]) and 301% higher among individuals hospitalized for non-COVID-19 LRTI (HR 3.01 [95% CI: 2.87-3.15]) compared to those hospitalized for non-LRTI.

CONCLUSION

The risk of new-onset LRTI following hospital discharge was high, particularly among those hospitalized for non-COVID-19 LRTI, but also for COVID-19 LRTI. These data suggest that immunizations targeting respiratory pathogens, including COVID-19, should be considered for adults hospitalized for LRTI prior to hospital discharge.

[Clinical characteristics and pathogens of infancy lower respiratory tract infections in infants with bronchopulmonary dysplasia]

OBJECTIVES

To study the clinical characteristics and pathogen features of infants with bronchopulmonary dysplasia (BPD) who were readmitted during infancy due to lower respiratory tract infections.

METHODS

A retrospective analysis was conducted on 128 preterm infants with BPD who were admitted for lower respiratory tract infections in Qingdao Women and Children's Hospital from January 2020 to December 2022. An equal number of non-BPD preterm infants admitted during the same period were selected as controls. General information, clinical characteristics, lung function parameters, and respiratory pathogen results were compared between the two groups.

RESULTS

Compared with the non-BPD group, the BPD group had a lower gestational age and birth weight, were more likely to experience shortness of breath, wheezing, and cyanosis, and had a longer duration of wheezing relief (P<0.05). Compared with the non-BPD group, the BPD group had lower lung function parameters, including tidal volume per kilogram of body weight, ratio of time to peak tidal expiratory flow to total expiratory time, ratio of volume at peak tidal expiratory flow to expiratory tidal volume, tidal expiratory flow at 25%, 50%, and 75% of tidal volume, and increased respiratory rate (P<0.05). The detection rates of gram-negative bacteria, such as Klebsiella pneumoniae and Acinetobacter baumannii, were higher in the BPD group than in the non-BPD group (P<0.05).

CONCLUSIONS

Infants with BPD who develop infancy lower respiratory tract infections require closer attention to the clinical characteristics such as shortness of breath, wheezing, and cyanosis. Lung function is characterized by obstructive changes and small airway dysfunction. Gram-negative bacteria, including Klebsiella pneumoniae and Acinetobacter baumannii, are more likely to be detected as respiratory pathogens.

Comparative analysis of clinical features of lower respiratory tract infection with respiratory syncytial virus and influenza virus in adults: a retrospective study

BACKGROUND

Respiratory syncytial virus (RSV) infection in adults remains less recognized and understood, both socially and clinically, compared to influenza virus infection. This retrospective study aims to delineate and compare the clinical manifestations of adult RSV and influenza virus infections in the lower respiratory tract, thereby enhancing awareness of RSV lower respiratory tract infection and providing strategic insights for its prevention and treatment.

METHODS

Clinical data from January 2019 to December 2020 were analyzed for 74 patients with RSV and 129 patients with influenza A/B virus lower respiratory tract infections who were admitted to respiratory or intensive care units. All patients had complete clinical data with positive IgM and negative IgG viral antibodies. Comparison parameters included onset timing, baseline data, clinical manifestations, supplementary examination results, treatment methods, and prognosis, while logistic regression was employed to ascertain the correlation of clinical features between the two patient groups.

RESULTS

In comparison to the influenza group, the RSV group presented less frequently with fever at admission but exhibited a higher incidence of dyspnea and wheezing on pulmonary auscultation (P < 0.01). RSV infection was more prevalent among patients with underlying diseases, particularly chronic obstructive pulmonary disease (COPD) and demonstrated a higher probability of co-infections, most notably with Mycoplasma (P < 0.01). The RSV group had significantly higher lymphocyte counts (P < 0.01) and exhibited more incidences of pleural thickening, pulmonary fibrosis, and emphysema (P < 0.05). The use of non-invasive mechanical ventilation was more common, and hospital stays were longer in the RSV group compared to the influenza group (P < 0.05). Logistic multivariate regression analysis further revealed that age and tachypnea incidence were significantly higher in the RSV group (P < 0.05).

CONCLUSION

Compared to influenza virus infection, adults with COPD are more susceptible to RSV infection. Moreover, RSV infection elevates the risk of co-infection with Mycoplasma and may lead to conditions such as pleural thickening, pulmonary fibrosis, and emphysema. The requirement for non-invasive mechanical ventilation is higher in RSV-infected patients, who also tend to have longer hospital stays. Therefore, greater awareness and preventive strategies against RSV infection are imperative.

Optimal site of care for administration of extended half-life respiratory syncytial virus (RSV) antibodies to infants in the United States (US)

INTRODUCTION

New extended half-life antibodies for the single-dose prevention of medically attended (MA) respiratory syncytial virus (RSV) lower respiratory tract infection (LRTI) have been developed for administration to all infants before or during their first RSV season. For infants born during the season, administration as soon as feasible after birth would provide optimal protection and minimize access disparities. The objective of this study was to assess the time from birth hospitalization discharge to the first outpatient visit (FOV) among US infants in order to determine optimal site of administration for the extended half-life antibody.

MATERIAL AND METHODS

This retrospective, observational, time-to-event analysis uses the Merative™ MarketScan® Commercial and Multi-State Medicaid Databases. Time to FOV is reported separately for the COVID-19 and recent pre-COVID-19 eras and for commercially insured and Medicaid infants.

RESULTS

Overall, 73.8 % of Medicaid infants had an FOV within 5 days as compared to 84.7 % of commercially insured infants. Estimates were higher during the COVID-19 era. Urban commercially insured infants had much higher FOV completion than their counterparts. Among Medicaid infants, urban Black and rural White infants were least likely to complete their FOV within 5 days of birth hospitalization discharge.

DISCUSSION AND CONCLUSION

FOV within 5 days after birth hospitalization discharge for Medicaid infants is substantially lower than that of commercially insured infants. Approximately 1 in 4 Medicaid infants and 1 in 8 infants with commercial insurance did not have an outpatient visit within 5 days of birth hospitalization discharge. For US infants born during the RSV season, administration of extended half-life RSV antibodies in the newborn nursery prior to discharge would ensure optimal uptake and minimize access disparities.

Point-of-care multiplex molecular diagnosis coupled with procalcitonin-guided algorithm for antibiotic stewardship in lower respiratory tract infection: a randomized controlled trial

OBJECTIVE

We aimed to show that coupling molecular syndromic respiratory panel (RP) testing with procalcitonin (PCT) measurement in the emergency department improves antibiotic (ATB) stewardship in lower respiratory tract infection.

METHODS

Open-label, prospective, randomized interventional trial, conducted from 2019 to 2022 in an adult emergency department. Patients with a suspicion of lower respiratory tract infection were randomized into an intervention arm (PCT measurement and point-of-care BIOFIRE RP2.1 plus testing, accompanied by a recommended ATB algorithm) or a standard of care (SOC) arm (PCT allowed as current practice). The primary endpoint was the duration of antibiotic exposure.

RESULTS

Four hundred fifty-one patients were randomized, median age 65 years (Q1-Q3: 49-77), the hospitalization rate was 59.9% (270/451), the median length of stay 5 days (Q1-Q3: 3 - 12), and the 28-day mortality rate 5.3% (23/451). The median duration of ATB exposure was 6 days (Q1-Q3: 0-9) and 5 days (Q1-Q3: 0-9) in the SOC and interventional arm respectively (p = 0.71). ATB was started in 29.6 % (67/226) and 33.8% (76/225) respectively (p = 0.54). The BIOFIRE RP2.1 plus identified at least one viral species in 112/225 patients (49.8%) of intervention arm. Two hundred twelve out of two hundred twenty-six (93.8%) SOC patients had PCT measurement. The adherence rate to algorithm in the intervention arm was 93.3 % (210/225).

CONCLUSION

Displaying PCT and real-time RP results to emergency physicians failed to significantly reduce ATB exposure in lower respiratory tract infection suspicions. However, the median ATB duration and rate of initiation were already low in the SOC arm using PCT measurement routinely.

Respiratory Syncytial Virus Infections in Neonates: A Persisting Problem

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections in young infants. It is an enveloped, single-stranded, nonsegmented, negative-strand RNA virus, a member of the family Pneumoviridae. Globally, RSV is responsible for 2.3% of deaths among neonates 0-27 days of age. Respiratory syncytial virus infection is most common in children aged below 24 months. Neonates present with cough and fever. Respiratory syncytial virus-associated wheezing is seen in 20% infants during the first year of life of which 2-3% require hospitalization. Reverse transcriptase polymerase chain reaction (RT-PCR) gives fast results and has higher sensitivity compared with culture and rapid antigen tests and are not affected by passively administered antibody to RSV. Therapy for RSV infection of the LRT is mainly supportive, and preventive measures like good hygiene and isolation are the mainstay of management. Standard precautions, hand hygiene, breastfeeding and contact isolation should be followed for RSV-infected newborns. Recent AAP guidelines do not recommend pavilizumab prophylaxis for preterm infants born at 29-35 weeks without chronic lung disease, hemodynamically significant congenital heart disease and coexisting conditions. RSV can lead to long-term sequelae such as wheezing and asthma, associated with increased healthcare costs and reduced quality of life.

Targeting the gut-lung axis by synbiotic feeding to infants in a randomized controlled trial

BACKGROUND

Formula-fed infants are at increased risk of infections. Due to the cross-talk between the mucosal systems of the gastrointestinal and respiratory tracts, adding synbiotics (prebiotics and probiotics) to infant formula may prevent infections even at distant sites. Infants that were born full term and weaned from breast milk were randomized to prebiotic formula (fructo- and galactooligosaccharides) or the same prebiotic formula with Lactobacillus paracasei ssp. paracasei F19 (synbiotics) from 1 to 6 months of age. The objective was to examine the synbiotic effects on gut microbiota development.

RESULTS

Fecal samples collected at ages 1, 4, 6, and 12 months were analyzed using 16S rRNA gene sequencing and a combination of untargeted gas chromatography-mass spectrometry/liquid chromatography-mass spectrometry. These analyses revealed that the synbiotic group had a lower abundance of Klebsiella, a higher abundance of Bifidobacterium breve compared to the prebiotic group, and increases in the anti-microbial metabolite d-3-phenyllactic acid. We also analyzed the fecal metagenome and antibiotic resistome in the 11 infants that had been diagnosed with lower respiratory tract infection (cases) and 11 matched controls using deep metagenomic sequencing. Cases with lower respiratory tract infection had a higher abundance of Klebsiella species and antimicrobial resistance genes related to Klebsiella pneumoniae, compared to controls. The results obtained using 16S rRNA gene amplicon and metagenomic sequencing were confirmed in silico by successful recovery of the metagenome-assembled genomes of the bacteria of interest.

CONCLUSIONS

This study demonstrates the additional benefit of feeding specific synbiotics to formula-fed infants over prebiotics only. Synbiotic feeding led to the underrepresentation of Klebsiella, enrichment of bifidobacteria, and increases in microbial degradation metabolites implicated in immune signaling and in the gut-lung and gut-skin axes. Our findings support future clinical evaluation of synbiotic formula in the prevention of infections and associated antibiotic treatment as a primary outcome when breastfeeding is not feasible.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01625273 . Retrospectively registered on 21 June 2012.

The Biofire® Filmarray® Pneumonia Plus panel for management of lower respiratory tract infection in mechanically-ventilated patients in the COVID-19 era: a diagnostic and cost-benefit evaluation

We assessed the diagnostic performance of the Biofire® Filmarray® Pneumonia Plus panel (FA-PP) compared to standard culture in Intensive Care Unit patients with suspected ventilator-associated lower respiratory tract infection in the COVID-19 era. We determined whether its implementation in routine diagnostic algorithms would be cost-beneficial from a hospital perspective. Of 163 specimens, 96 (59%) returned negative results with FA-PP and conventional culture, and 29 specimens (17.8%) were positive with both diagnostic methods and yielded concordant qualitative bacterial identification/isolation. Thirty-nine specimens (23.9%) gave discordant results (positive via FA-PP and negative via culture). Real-life adjustments of empirical antimicrobial therapy (EAT) after FA-PP results resulted in additional costs beyond EAT alone of 1868.7 €. Adequate EAT adjustments upon FA-PP results would have resulted in a saving of 6675.8 €. In conclusion, the data presented supports the potential utility of FA-PP for early EAT adjustment in patients with ventilator-associated lower respiratory tract infection.

The value of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit

Heart failure (HF) represents an important cause of morbidity and mortality in children. It is mostly caused by congenital heart disease (CHD) and cardiomyopathy. The Ross HF classification was developed to assess severity in infants and has subsequently been modified to apply to all pediatric ages. The modified Ross classification for children provides a numeric score comparable with the New York Heart Association (NYHA) HF classification for adults. The aim of this work is to investigate the role of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit (PICU). One hundred and sixty-four children with severe LRTI admitted to the PICU were enrolled in this prospective cohort study, which was carried out at Assiut University Children Hospital, from the start of July 2021 up to the end of December 2021. Sixty patients (36.6%) of studied cases with severe LRTI admitted to PICU had HF. Out of these, 37 (61.7%) had mild HF; 17 (28.3%) had moderate HF, while six cases (10%) had severe HF according to the modified Ross score. The value of modified Ross score was significantly higher in children with heart failure with sensitivity and specificity 100% with cutoff value of 2. Admission to NICU, history of previous ventilation, and prematurity were higher in patients who developed HF. Patients with pulmonary hypertension (PH) and those with raised neutrophil lymphocyte ratio were significantly higher in the group of patients with moderate and severe degree of HF.   Conclusion: Modified Ross score is a simple clinical score which may help in assessing and predicting children with severe LRTI. What is Known: • Hear failure is common complication to lower respiratory tract infection. • Modified Ross score was used to predict and classify heart failure in adult with lower respiratory infection. What is New: • Modified Ross score found to be of value in prediction of heart failure in children with lower respiratory tract infection.

Vitamin D supplementation and lower respiratory tract infection in infants: a nested case-control study

PURPOSE

To assess the association between vitamin D (VD) supplementation and the risk of lower respiratory tract infection (LRTI) among infants.

METHODS

This is a nested case-control study from an ongoing prospective birth cohort in Wuhan from 2013. Cases were subjects free of neonatal pneumonia but later developed LRTI during infancy, who were matched with five randomly selected controls by infant sex, birth year, and birth season. We included 190 cases and 950 controls in the final analysis. The primary outcome was the first LRTI incident and the exposure was VD supplementation from birth to the index endpoint. The association between VD supplementation and LRTI risk was assessed using the Cox proportional-hazards regression model.

RESULTS

Infants taking supplements had a 59% relative reduction in the hazard ratio of LRTI (HR = 0.41; 95% CI 0.26, 0.64) compared to those not supplemented. There was a linear relationship between LRTI risk and VD supplementation within range of 0-603 IU/day: for each 100 IU per day increment in VD supplementation, infants experienced a 21% lower risk of developing LRTI (adjusted HR: 0.79; 95% CI 0.71, 0.89). The linear relationship was stably observed in the sensitivity analyses as well.

CONCLUSIONS

VD supplementation was associated with the reduced risk of LRTI throughout infancy, and the optimal supplementation dose for infants may be beyond the current recommendation.

Neighborhood environmental factors linked to hospitalizations of older people for viral lower respiratory tract infections in Spain: a case-crossover study

BACKGROUND

Lower respiratory tract viral infection (LRTI) is a significant cause of morbidity-mortality in older people worldwide. We analyzed the association between short-term exposure to environmental factors (climatic factors and outdoor air pollution) and hospital admissions with a viral LRTI diagnosis in older adults.

METHODS

We conducted a bidirectional case-crossover study in 6367 patients over 65 years of age with viral LRTI and residential zip code in the Spanish Minimum Basic Data Set. Spain's State Meteorological Agency was the source of environmental data. Associations were assessed using conditional logistic regression. P-values were corrected for false discovery rate (q-values).

RESULTS

Almost all were hospital emergency admissions (98.13%), 18.64% were admitted to the intensive care unit (ICU), and 7.44% died. The most frequent clinical discharge diagnosis was influenza (90.25%). LRTI hospital admissions were more frequent when there were lower values of temperature and O₃ and higher values of relative humidity and NO₂. The regression analysis adjusted by temperatures and relative humidity showed higher concentrations at the hospital admission for NO₂ [compared to the lag time of 1-week (q-value< 0.001) and 2-weeks (q-value< 0.001)] and O₃ [compared to the lag time of 3-days (q-value< 0.001), 1-week (q-value< 0.001), and 2-weeks (q-value< 0.001)] were related to a higher odds of hospital admissions due to viral LRTI. Moreover, higher concentrations of PM₁₀ at the lag time of 1-week (q-value = 0.023) and 2-weeks (q-value = 0.002), and CO at the lag time of 3-days (q-value = 0.023), 1-week (q-value< 0.001) and 2-weeks (q-value< 0.001)], compared to the day of hospitalization, were related to a higher chances of hospital admissions with viral LRTI.

CONCLUSION

Unfavorable environmental factors (low temperatures, high relative humidity, and high concentrations of NO₂, O₃, PM₁₀, and CO) increased the odds of hospital admissions with viral LRTI among older people, indicating they are potentially vulnerable to these environmental factors.

Incidence of community acquired lower respiratory tract disease in Bristol, UK during the COVID-19 pandemic: A prospective cohort study

Background

The emergence of COVID-19 and public health measures implemented to reduce SARS-CoV-2 infections have both affected acute lower respiratory tract disease (aLRTD) epidemiology and incidence trends. The severity of COVID-19 and non-SARS-CoV-2 aLRTD during this period have not been compared in detail.

Methods

We conducted a prospective cohort study of adults age ≥18 years admitted to either of two acute care hospitals in Bristol, UK, from August 2020 to November 2021. Patients were included if they presented with signs or symptoms of aLRTD (e.g., cough, pleurisy), or a clinical or radiological aLRTD diagnosis.

Findings

12,557 adult aLRTD hospitalisations occurred: 10,087 were associated with infection (pneumonia or non-pneumonic lower respiratory tract infection [NP-LRTI]), 2161 with no infective cause, with 306 providing a minimal surveillance dataset. Confirmed SARS-CoV-2 infection accounted for 32% (3178/10,087) of respiratory infections. Annual incidences of overall, COVID-19, and non- SARS-CoV-2 pneumonia were 714.1, 264.2, and 449.9, and NP-LRTI were 346.2, 43.8, and 302.4 per 100,000 adults, respectively. Weekly incidence trends in COVID-19 aLRTD showed large surges (median 6.5 [IQR 0.7-10.2] admissions per 100,000 adults per week), while other infective aLRTD events were more stable (median 14.3 [IQR 12.8-16.4] admissions per 100,000 adults per week) as were non-infective aLRTD events (median 4.4 [IQR 3.5-5.5] admissions per 100,000 adults per week).

Interpretation

While COVID-19 disease was a large component of total aLRTD during this pandemic period, non- SARS-CoV-2 infection still caused the majority of respiratory infection hospitalisations. COVID-19 disease showed significant temporal fluctuations in frequency, which were less apparent in non-SARS-CoV-2 infection. Despite public health interventions to reduce respiratory infection, disease incidence remains high.

Funding

AvonCAP is an investigator-led project funded under a collaborative agreement by Pfizer.

Detection of influenza and non-influenza respiratory viruses in lower respiratory tract specimens among hospitalized adult patients and analysis of the clinical outcome

BACKGROUND

Lower respiratory tract infection (LRTI) is one of the most fatal diseases for adults. Influenza is a well-recognized cause of severe pneumonia; however, the outcomes of LRTI caused by non-influenza respiratory viruses (NIRVs) have not been sufficiently investigated. This study aimed to describe the characteristics and outcomes of LRTI associated with respiratory viruses (RVs) in adults.

MATERIALS/METHODS

A retrospective review was performed using medical records of adult patients whose lower respiratory tract (LRT) specimens (endotracheal aspirate and bronchoalveolar lavage fluid) tested positive for RVs using multiplex PCR. Underlying comorbidities, laboratory data, and clinical outcomes were analyzed.

RESULTS

Among the 808 LRT specimens collected from 666 adult patients, RV was identified in 115 specimens (14%) from 106 patients (16%). The underlying comorbidities and laboratory data did not differ between patients with influenza- and NIRV-related LRTI. The 14-day and 30-day mortality rates were higher in the influenza group than in the NIRV group (24% versus 7%, p = 0.03 and 33% versus 13%, p = 0.02, respectively), whereas the 90-day mortality rate did not. In a multivariate Cox model to predict 90-day mortality, shock and acute kidney injury independently predicted a higher mortality rate (hazard ratio (HR): 4.28, 95% CI: 1.46-12.58, p = 0.01 and HR: 2.80, 95% CI: 1.28-6.15, p = 0.01, respectively), whereas the detection of influenza did not.

CONCLUSIONS

Influenza and NIRVs were associated with increased mortality due to LRTI in adults. Therefore, NIRVs are among key pathogens causing LRTI and should not be neglected by clinicians.

Incidence of community acquired lower respiratory tract disease in Bristol, UK during the COVID-19 pandemic: A prospective cohort study

BACKGROUND

The emergence of COVID-19 and public health measures implemented to reduce SARS-CoV-2 infections have both affected acute lower respiratory tract disease (aLRTD) epidemiology and incidence trends. The severity of COVID-19 and non-SARS-CoV-2 aLRTD during this period have not been compared in detail.

METHODS

We conducted a prospective cohort study of adults age ≥18 years admitted to either of two acute care hospitals in Bristol, UK, from August 2020 to November 2021. Patients were included if they presented with signs or symptoms of aLRTD (e.g., cough, pleurisy), or a clinical or radiological aLRTD diagnosis.

FINDINGS

12,557 adult aLRTD hospitalisations occurred: 10,087 were associated with infection (pneumonia or non-pneumonic lower respiratory tract infection [NP-LRTI]), 2161 with no infective cause, with 306 providing a minimal surveillance dataset. Confirmed SARS-CoV-2 infection accounted for 32% (3178/10,087) of respiratory infections. Annual incidences of overall, COVID-19, and non- SARS-CoV-2 pneumonia were 714.1, 264.2, and 449.9, and NP-LRTI were 346.2, 43.8, and 302.4 per 100,000 adults, respectively. Weekly incidence trends in COVID-19 aLRTD showed large surges (median 6.5 [IQR 0.7-10.2] admissions per 100,000 adults per week), while other infective aLRTD events were more stable (median 14.3 [IQR 12.8-16.4] admissions per 100,000 adults per week) as were non-infective aLRTD events (median 4.4 [IQR 3.5-5.5] admissions per 100,000 adults per week).

INTERPRETATION

While COVID-19 disease was a large component of total aLRTD during this pandemic period, non- SARS-CoV-2 infection still caused the majority of respiratory infection hospitalisations. COVID-19 disease showed significant temporal fluctuations in frequency, which were less apparent in non-SARS-CoV-2 infection. Despite public health interventions to reduce respiratory infection, disease incidence remains high.

FUNDING

AvonCAP is an investigator-led project funded under a collaborative agreement by Pfizer.

Multidrug-resistant bacteria with ESBL genes: a growing threat among people living with HIV/AIDS in Nepal

BACKGROUND

Bacterial opportunistic infections are common in people living with HIV/AIDS (PLHA). Besides HIV-TB co-infection, lower respiratory tract infections (LRTIs) due to multidrug-resistant (MDR) bacteria cause significant morbidity and mortality among PLHA. This study identified bacterial co-infection of the lower respiratory tract and detected plasmid-mediated bla_TEM and bla_CTX-M genes among Extended-Spectrum β-Lactamase (ESBL) producing isolates from sputum samples in PLHA.

METHODS

A total of 263 PLHA with LRTIs were enrolled in this study, out of which, 50 were smokers, 70 had previous pulmonary tuberculosis, and 21 had CD4 count < 200 cells/µl. Sputum samples collected from PLHA were processed with standard microbiological methods to identify the possible bacterial pathogens. The identified bacterial isolates were assessed for antibiotic susceptibility pattern using modified Kirby Bauer disk diffusion method following Clinical Laboratory Standard Institute (CLSI) guidelines. In addition, plasmid DNA was extracted from MDR and ESBL producers for screening of ESBL genes; bla_CTX-M and bla_TEM by conventional PCR method using specific primers.

RESULTS

Of 263 sputum samples, 67 (25.48%) showed bacterial growth. Among different bacterial pathogens, Klebsiella pneumoniae, (17; 25.37%) was the most predominant, followed by Haemophillus influenzae, (14; 20.90%) and Escherichia coli, (12; 17.91%). A higher infection rate (4/8; 50%) was observed among people aged 61-70 years, whereas no infection was observed below 20 years. About 30.0% (15/50) of smokers, 32.86% (23/70) cases with previous pulmonary tuberculosis, and 52.38% (11/21) with CD4 count < 200 cells/µl had bacterial LRTIs. Among 53 bacterial isolates excluding H. influenzae, 28 isolates were MDR and 23 were ESBL producers. All ESBL producers were sensitive to colistin and polymyxin B. Among ESBL producers, 47.83% (11/23) possessed bla_CTX-M, 8.6% (2/23) were positive for bla_TEM gene, and 43.48% (10/23) possessed both ESBL genes.

CONCLUSION

The increasing rate of MDR bacterial infections, mainly ESBL producers of LRTIs causes difficulty in disease management, leading to high morbidity and mortality of PLHA. Hence, it is crucial to know the antibiogram pattern of the isolates to recommend effective antimicrobial therapy to treat LRTIs in PLHA.

Development and evaluation of a multiplex quantitative polymerase chain reaction assay for detecting bacteria associated with lower respiratory tract infection

OBJECTIVES

This study aimed to establish a multiplex quantitative polymerase chain reaction (MQ-PCR) assay for 12 bacterial pathogens found in lower respiratory tract infection (LRTI) and to evaluate its performance in a cohort of 211 patients with LRTI.

METHODS

The study was divided into two stages: a pilot study to establish the methodology and a clinical validation study to evaluate its performance. In the pilot study, we established the MQ-PCR and analyzed its performance regarding limits of detection, reproducibility, specificity, and efficiency. In the clinical validation study, we obtained 211 sputum and/or bronchoalveolar lavage fluid (BALF) samples and detected pathogens by MQ-PCR. The MQ-PCR time was 3 h from sample collection to complete pathogen detection.

RESULTS

The limit of detection was 1000 copies/ml, and the maximum efficiency was >95%. When cutoffs of ≥10⁵ copies/ml in sputum and ≥10⁴ copies/ml in BALF were applied, the sensitivity, specificity, and positive and negative predictive values of the MQ-PCR were 77% (95% confidence interval [CI] 67-88%), 94% (95% CI 93-95%), 25% (95% CI 19-31%), and 99% (95% CI 99-100%), respectively.

CONCLUSIONS

This study demonstrates that the new MQ-PCR assay is time-saving, more effective and sensitive, and brings us closer to mainstream adoption of quantitative molecular detection of bacteria.

Multiplex detection of five common respiratory pathogens from bronchoalveolar lavages using high resolution melting curve analysis

Background

The study describes the application of the multiplex high-resolution melting curve (MHRM) assay for the simultaneous detection of five common bacterial pathogens (Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii and Escherichia coli) directly from bronchoalveolar lavage samples.

Results

Our MHRM assay successfully identified all five respiratory pathogens in less than 5 h, with five separate melting curves with specific melt peak temperatures (Tm). The different Tm were characterized by peaks of 78.1 ± 0.4 °C for S. aureus, 83.3 ± 0.1 °C for A. baumannii, 86.7 ± 0.2 °C for E. coli, 90.5 ± 0.1 °C for K. pneumoniae, 94.5 ± 0.2 °C for P. aeruginosa. The overall sensitivity and specificity of MHRM were 100% and 88.8–100%, respectively.

Conclusions

Our MHRM assay offers a simple and fast alternative to culture approach for simultaneous detection of five major bacterial lower respiratory tract infection pathogens. Utilization of this assay can help clinicians initiate prompt and appropriate antimicrobial treatment, towards reducing the morbidity and mortality of severe respiratory infections.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-022-02558-2.

Risk of lower respiratory tract infections: a genome-wide association study with Mendelian randomization analysis in three independent European populations

OBJECTIVE

Lower respiratory tract infections (LRTIs) are a leading cause of morbidity and mortality worldwide. Few studies have previously investigated genetic susceptibility and potential risk factors for LRTI.

METHODS

We used data from the UK Biobank, Trøndelag Health Study (HUNT), and FinnGen to conduct a genome-wide association study (GWAS). Cases were subjects hospitalized with LRTI, and controls were subjects with no such hospitalization. We conducted stratification and interaction analyses to evaluate whether the genetic effect of LRTI differed by sex or smoking. Mendelian randomization (MR) analyses were conducted to identify the unconfounded relationship between cardiometabolic risk factors and LRTI.

RESULTS

A total of 25 320 cases and 575 294 controls were included. The 15q25.1 locus reached genome-wide significance in the meta-analysis (rs10519203: OR 0.94, p 3.87e-11). The protective effect of effect allele of rs10519203 was present among smokers (OR 0.90, 95%CI 0.87-0.92, p 1.38e-15) but not among never-smokers (OR 1.01, 95%CI 0.97-1.06, p 5.20e-01). In MR analyses, we found that increasing body mass index (OR 1.31, 95%CI 1.24-1.40, p 3.78e-18), lifetime smoking (OR 2.83, 95%CI 2.34-3.42, p 6.56e-27), and systolic blood pressure robustly increased the risk of LRTIs (OR 1.11, 95%CI 1.02-1.22, p 1.48e-02).

CONCLUSION

A region in 15q25.1 was strongly associated with LRTI susceptibility. Reduction in the prevalence of smoking, overweight, obesity, and hypertension may reduce the disease burden of LRTIs.

Prevalence of viral pathogens in a sample of hospitalized Egyptian children with acute lower respiratory tract infections: a two-year prospective study

BACKGROUND

Viral pneumonias are a major cause of childhood mortality. Proper management needs early and accurate diagnosis. This study objective is to investigate the viral etiologies of pneumonia in children.

RESULTS

This prospective study enrolled 158 and 101 patients in the first and second year, respectively, and their mean age was 4.72 ± 2.89. Nasopharyngeal swabs were collected and subjected to virus diagnosis by reverse transcription polymerase chain reaction (RT-PCR). Viral etiologies of pneumonia were evidenced in 59.5% of the samples in the first year, all of them were affirmative for influenza A, 2 samples were affirmative for Human coronavirus NL63, and one for Human coronavirus HKU1. In the second year, 87% of patients had a viral illness. The most prevalent agents are human metapneumovirus which was detected in 44 patients (43.6%) followed by human rhinovirus in 35 patients (34.7%) and then parainfluenza-3 viruses in 33 patients (32.7%), while 14 patients had a confirmed diagnosis for both Pan coronavirus and Flu-B virus.

CONCLUSIONS

Viral infection is prevalent in the childhood period; however, the real magnitude of viral pneumonia in children is underestimated. The reverse transcriptase polymerase chain reaction has to be a vital tool for epidemiological research and is able to clear the gaps in-between clinical pictures and final diagnoses.

Incidence of lower respiratory tract infection and associated viruses in a birth cohort in the Philippines

Background

Lower respiratory tract infection (LRTI) is an important cause of morbidity and mortality in infants and young children. However, the etiological role of viruses and the timing of developing LRTI are not well defined.

Methods

We analyzed the data of a prospective cohort study in the Philippines as a birth cohort. We detected LRTI among children who visited healthcare facilities with respiratory symptom, and collected nasopharyngeal swabs for virus detection. We analyzed the incidence rates (IRs) and cumulative proportion of LRTI and severe LRTI by age group and each virus detected.

Results

A total of 350 LRTI episodes were observed from 473 child-years yielded from 419 children. The IRs of LRTI were 70.8, 70.7, and 80.8 per 100 child-years for 0–5, 6–11, and 12–23 months of age, respectively. By 12 months of age, 45% of children developed LRTI at least once. Rhinovirus and respiratory syncytial virus were the most frequently detected viruses in all age groups. However, the IRs of influenza virus were low especially at 0–5 months of age.

Conclusions

We identified various patterns of age-specific IRs of LRTI and severe LRTI for different viruses, which should be considered to establish more effective interventions including vaccinations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07289-3.

Effectiveness of palivizumab immunoprophylaxis in infants with respiratory syncytial virus disease in Colombia

INTRODUCTION

Respiratory syncytial virus (RSV) is one of the most important childhood infections.

OBJECTIVE

To evaluate the effectiveness and safety of palivizumab immunoprophylaxis in preterm infants at a high risk of severe respiratory syncytial virus infection during the RSV season in Colombia.

METHODOLOGY

A prospective observational non-comparative multicenter study in six Colombian cities. At the beginning of the RSV infection season, palivizumab prophylaxis, up to five doses, was administered to infants born at ≤32 weeks of gestation, infants younger than six months, infants under one year of age with bronchopulmonary dysplasia (BPD), infants one year or less of age with hemodynamically significant acyanotic and non-acyanotic congenital heart disease (CHD), and with follow-up during the immunoprophylaxis until one month after the last dose.

RESULTS

The study enrolled 600 patients, 91.8% of which were born at ≤ 32 weeks of gestation. BPD was observed in 54.9% of infants. 49% were born at < 32 weeks gestation and presented BPD. 6.9% had hemodynamically significant acyanotic and non-acyanotic CHD 53.3% received three or more doses of palivizumab. The mean interval between doses was 39.6 days. 1.8% of patients were hospitalized due to a confirmed RSV infection. Overall mortality was 1.2%, whereas the mortality by RSV in infants undergoing prophylaxis was 0.2%.

CONCLUSIONS

Palivizumab was a clinically effective, well-tolerated treatment in the Colombian population. The safety profile of palivizumab reflects the findings from previous studies in developed countries.

Systemic corticosteroid as an adjunctive treatment for lower respiratory tract infection in children with severe motor and intellectual disabilities

INTRODUCTION

Children with severe motor and intellectual disabilities (SMID) are susceptible to severe lower respiratory tract infection (LTRI). As SMID patients are prone to develop recurrent wheezing and are often diagnosed with bronchial asthma, they frequently receive systemic corticosteroids as an adjunctive treatment for LRTIs. However, the efficacy of corticosteroid therapy for LTRIs in SMID children is unclear. We investigated whether or not corticosteroid therapy was associated with better clinical outcomes for SMID children with LRTIs.

METHODS

Our retrospective study enrolled 217 SMID children 1-15 years old hospitalized for LTRIs. We compared the clinical characteristics and outcomes between patients with and without corticosteroid therapy.

RESULTS

Of the 217 patients, 29 (13.3%) received corticosteroid therapy. The proportion of patients with a history of bronchial asthma was higher and LRTI was more severe in patients with corticosteroid therapy than in those without the therapy. The length of hospital stay (LOHS) was significantly longer in patients with corticosteroid therapy (median 13 days) than in those without corticosteroid therapy (median 9 days) (P = 0.02). The same tendency was shown for the LOHS in patients with severe or moderate LRTI, although not to a significant extent.

CONCLUSION

Systemic corticosteroid therapy was not associated with better clinical outcomes in SMID children with LRTIs, even if the patients suffer from severe LRTIs. Corticosteroids should be used cautiously for LRTIs in SMID children because bronchial asthma is likely to be overdiagnosed in these children.

The effect of recombinant human interferon α1b treatment of infants hospitalized with lower respiratory tract infection on subsequent wheezing

OBJECTIVE

To investigate the impact of recombinant human interferon α1b (rhIFNα1b) treatment in infants hospitalized with lower respiratory tract infections on subsequent wheezing.

METHODS

The clinical data of infants (n=540) with viral pneumonia, wheezy bronchitis, or bronchiolitis hospitalized in 19 Chinese hospitals from June 2009 to June 2015 were retrospectively analyzed. The parameters relevant to wheezing episodes within the last year were collected by telephone and questionnaires. The rhIFNα1b treatment group (n=253) and control group (n=287) were compared in terms of wheezing episodes within the last year. Moreover, the wheezing group (95 cases) and non-wheezing group (445 cases) were compared.

RESULTS

Out of 540 cases, 95 (17.6%) experienced wheezing episodes, 13.8% (35/253) cases treated with rhIFNα1b, and 20.9% (60/287) cases without rhIFNα1b experienced wheezing episodes within the last year. The rhIFNα1b treatment significantly improved wheezing episodes within the last year, compared with the control peers (p=0.031). Single-factor regression showed statistically significant differences between the wheezing and non-wheezing groups in terms of age, rhIFNα1b use, childhood and family history of allergy, housing situation, and feeding history (p<0.05). Binary logistic regression showed a childhood history of allergy (OR=2.14, p=0.004), no rhIFNα1b use (OR=1.70, p=0.028), and living in a crowded house (OR=1.92, p=0.012) might be risk factors of subsequent wheezing. Accordingly, breastfeeding (OR=0.44, p=0.008) and hospitalization age of ≤1-year-old (OR=0.58, p=0.024) were protective factors.

CONCLUSIONS

Early use of rhIFNα1b in infants hospitalized with lower respiratory tract infections and breastfeeding could prevent subsequent wheezing. Living in a crowded house could promote subsequent wheezing.

Lower respiratory tract infection hospitalizations among American Indian/Alaska Native adults, Indian Health Service and Alaska Region, 1998-2014

OBJECTIVES

This study describes the changes in lower respiratory tract infection (LRTI) rates from 1998 to 2014 among hospitalized American Indian/Alaska Native (AI/AN) adults residing in Alaska and other Indian Health Service (IHS) regions.

METHODS

Age-adjusted hospital discharge rates and rate ratios were calculated from the IHS Direct and Contract Health Services Inpatient Dataset, IHS National Patient Information Reporting System for AI/AN adults ≥18 years, hospitalized at an IHS-operated, tribally operated, or contract hospital with an LRTI-associated diagnosis during 1998-2014.

RESULTS

Overall, there were 13 733 LRTI-associated hospitalizations in Alaska (1998-2014), with an age-adjusted rate of 13.7/1000 adults. Among non-Alaska (non-AK) AI/AN, there were a total of 79 170 hospitalizations, with a rate of 8.6/1000 adults. In the pre-PCV7 and pre-PCV13 periods, LRTI rates were higher in Alaska (AK) AI/AN (12.4 and 14.1, respectively) when compared to non-AK AI/AN (10.1 and 9.1, respectively) (P < 0.0001). In the post-PCV7 and post-PCV13 periods, LRTI rates were also higher in AK (13.5 and 15.0, respectively) compared to non-AK (9.2 and 7.3, respectively) (P < 0.0001).

CONCLUSIONS

Over the study period, a 26% increase in rates of LRTI among adult AI/AN residing in AK compared with a 38% decrease in rates among AI/AN residing in non-AK were observed. This disparity is likely due to a variety of factors such as tobacco use, crowding, etc. Strategies to reduce LRTI in AI/AN adults are needed.

C-reactive protein or procalcitonin combined with rhinorrhea for discrimination of viral from bacterial infections in hospitalized adults in non-intensive care units with lower respiratory tract infections

BACKGROUND

Whether procalcitonin (PCT) or C-reactive protein (CRP) combined with certain clinical characteristics can better distinguish viral from bacterial infections remains unclear. The aim of the study was to assess the ability of PCT or CRP combined with clinical characteristics to distinguish between viral and bacterial infections in hospitalized non-intensive care unit (ICU) adults with lower respiratory tract infection (LRTI).

METHODS

This was a post-hoc analysis of a randomized clinical trial previously conducted among LRTI patients. The ability of PCT, CRP and PCT or CRP combined with clinical symptoms to discriminate between viral and bacterial infection were assessed by portraying receiver operating characteristic (ROC) curves among patients with only a viral or a typical bacterial infection.

RESULTS

In total, 209 infected patients (viral 69%, bacterial 31%) were included in the study. When using CRP or PCT to discriminate between viral and bacterial LRTI, the optimal cut-off points were 22 mg/L and 0.18 ng/mL, respectively. When the optimal cut-off for CRP (≤ 22 mg/L) or PCT (≤ 0.18 ng/mL) combined with rhinorrhea was used to discriminate viral from bacterial LRTI, the AUCs were 0.81 (95% CI: 0.75-0.87) and 0.80 (95% CI: 0.74-0.86), which was statistically significantly better than when CRP or PCT used alone (p < 0.001). When CRP ≤ 22 mg/L, PCT ≤ 0.18 ng/mL and rhinorrhea were combined, the AUC was 0.86 (95% CI: 0.80-0.91), which was statistically significantly higher than when CRP (≤ 22 mg/L) or PCT (≤ 0.18 ng/mL) was combined with rhinorrhea (p = 0.011 and p = 0.021).

CONCLUSIONS

Either CRP ≤ 22 mg/L or PCT ≤ 0.18 ng/mL combined with rhinorrhea could help distinguish viral from bacterial infections in hospitalized non-ICU adults with LRTI. When rhinorrhea was combined together, discrimination ability was further improved.

The association between bacteria colonizing the upper respiratory tract and lower respiratory tract infection in young children: a systematic review and meta-analysis

BACKGROUND

Bacteria colonizing the upper respiratory tract (URT) of young children play a key role in the pathogenesis of lower respiratory tract infection (LRTI).

OBJECTIVES

To systematically review the literature on the association between bacteria colonizing the URT and LRTI among young children.

DATA SOURCES

MEDLINE, Academic Search Premier, Africa-Wide Information and CINAHL, Scopus and Web of Science.

STUDY ELIGIBILITY CRITERIA

Studies published between 1923 and 2020, investigating URT bacteria from LRTI cases and controls.

PARTICIPANTS

Children under 5 years with and without acute LRTI.

METHODS

Three reviewers independently screened titles, abstracts and full texts. Meta-analysis was done using Mantel-Haenszel fixed- or random-effects models.

RESULTS

Most eligible studies (41/50) tested nasopharyngeal specimens when investigating URT bacteria. Most studies were of cross-sectional design (44/50). Twenty-four studies were performed in children in lower- or lower-middle-income countries (LMICs). There was higher prevalence of Haemophilus influenzae (pooled OR 1.60; 95% CI 1.23-2.07) and Klebsiella spp. (pooled OR 2.04; 95% CI 1.17-3.55) from URT specimens of cases versus controls. We observed a positive association between the detection of Streptococcus pneumoniae from URT specimens and LRTI after excluding studies where there was more antibiotic treatment prior to sampling in cases vs. controls (pooled OR 1.41; 95% CI 1.04-1.90). High density colonization with S. pneumoniae (>6.9 log10 copies/mL) was associated with an increased risk for LRTI. The associations between both Streptococcus and Haemophilus URT detection and LRTI were supported, at genus level, by 16S rRNA sequencing. Evidence for the role of Moraxella catarrhalis and Staphylococcus aureus was inconclusive.

CONCLUSIONS

Detection of H. influenzae or Klebsiella spp. in the URT was associated with LRTI, while evidence for association with S. pneumoniae was less conclusive. Longitudinal studies assessing URT microbial communities, together with environmental and host factors are needed to better understand pathogenesis of childhood LRTI.

BioFire® FilmArray® Pneumonia Panel for Severe Lower Respiratory Tract Infections: Subgroup Analysis of a Randomized Clinical Trial

INTRODUCTION

The epidemiology of severe lower respiratory tract infections (LRTI) is constantly changing. We aimed to describe it using the BioFire^® FilmArray^® Pneumonia plus (PNplus) Panel.

METHODS

In a sub-study of the PROGRESS trial, sputum samples of 90 patients with sepsis and LRTI were retrospectively studied. The primary endpoint was the comparative detection rate of pathogens between conventional microbiology and PNplus Panel; secondary endpoints were microbiology and the association with the inflammatory host response.

RESULTS

Fifty-six patients with community-acquired pneumonia without risk factors for multidrug-resistant (MDR) pathogens and another 34 patients with risk factors for MDR were studied; median pneumonia severity index (PSI) was 113 (88-135). PNplus detection rate was 72.2% compared to 10% by conventional microbiology (p < 0.001); Streptococcus pneumoniae was the most common pathogen. PSI and procalcitonin were greater among patients with bacterial pathogens than viral pathogens. Median procalcitonin was 0.49 ng/ml and 0.18 ng/ml among patients with ≥ 10⁵ and < 10⁵ copies/ml of detected bacteria, respectively (p = 0.004). Resistance reached 14.4%.

CONCLUSION

PNplus detects severe pneumonia pathogens at a greater rate than conventional microbiology. High levels of inflammation accompany bacterial detection.

TRIAL REGISTRATION

PROGRESS, ClinicalTrials.gov NCT03333304, 06/11/2017.

Bacterial profile and drug susceptibility among adult patients with community acquired lower respiratory tract infection at tertiary hospital, Southern Ethiopia

BACKGROUND

Lower respiratory tract infection is a global problem accounting over 50 million deaths annually. Here, we determined the bacterial profile and antimicrobial susceptibility pattern of lower respiratory tract infections among adult patients attending at Tertiary Hospital, Southern Ethiopia.

METHODS

A cross sectional study was conducted among adult patients with lower respiratory infection at the medical outpatient department of the Hospital. A sputum sample was collected and processed for bacterial culture and antimicrobial susceptibility test. Semi structured questionnaires were used to collect data. SPSS version 22 software was used for statistical analysis and a p value of < 0.05 was considered as statistically significant.

RESULTS

Out of 406 sputum samples of participants 136(33.5%) were culture positive for 142 bacterial isolates. Klebsiella pneumoniae 36(25.4%) was the predominant isolate followed by Pseudomonas species 25(17.6%). Gram-negative bacteria were sensitive to cefepime (86.0%) and ciprofloxacin (77.8%) antibiotics while gram-positive (76.5%) to clindamycin.

CONCLUSION

Community acquired lower respiratory tract Infection was highly prevalent in the study area and the isolates showed resistant to common antibiotics such as ampicillin, augmentin, ceftazidime and tetracycline. Therefore, culture and susceptibility test is vital for appropriate management of lower respiratory tract infection in the study area.

Elderly patients with concurrent hip fracture and lower respiratory tract infection: the pathogens and prognosis over different bedridden periods

BACKGROUND

Elderly patients who experience hip fractures often become bedridden and are at risk of developing lower respiratory tract infections. The current study was to investigate the etiology and bacterial drug resistance patterns of elderly patients with hip fractures and lower respiratory tract infections on prolonged bedridden time and to determine their prognosis.

METHODS

Patients diagnosed with hip fractures admitted from May 2015 to April 2017 were included. The basic characteristics including the patients' gender, age, fracture type, operation mode, bedridden duration, length of hospital stay, prognosis, past medical history, routine bloodwork, C-reactive protein (CRP), procalcitonin (PCT), blood biochemistry, blood gas analysis, glycosylated hemoglobin (HbA1C%), sputum smear, sputum culture, and anti-infection and related therapy were recorded. All patients were classified into three groups based on bed rest duration, including short-term (<1 month), mid-term (1-12 months), and long-term (> 12 months). The correlation between the bedridden time and the patients' basic characteristics, disease history, laboratory examination results, pathogen, anti-infection, and related therapy were evaluated. The risk factors related to the prognosis of the disease were investigated.

RESULTS

Prolonged bed rest in patients led to an increase in hospitalization time, mortality rates, and decreased serum albumin levels (P < 0.05). Sputum bacteriological culture results showed that, with bed rest prolongation, the proportion of Pseudomonas aeruginosa and fungal infections increased. Binomial logistic regression of pulmonary infection prognosis, glucocorticoid use during the anti-infective period, prolonged bedridden time, and serum albumin level showed that intravenous use of glucocorticoid during anti-infective treatment, bed rest > 1 year, and low serum albumin level were related to poor prognosis.

CONCLUSION

Elderly hip fracture patients with prolonged bedridden time had an increased chance of opportunistic pulmonary infection and decreased nutritional status. Glucocorticoids should be used cautiously.

[Analysis of systemic cytokine levels in silicosis complicated with pulmonary infection]

Objective: To investigate the changes of cytokine profile in elderly patients with silicosis and lower respiratory tract infection and its clinical significance. Methods: In Oclober 2019, a retrospective study was conducted to select 167 elderly patients with silicosis from Xuzhou Mining Group General Hospital as subjects, including 115 patients with silicosis and lower respiratory tract infection as infected group, including 41 patients with stage I silicosis, 38 patients with stage II silicosis and 36 patients with stage III silicosis. There were 52 cases of silicosis without lower respiratory tract infection as non-infected group, and 48 cases of healthy examination in our hospital were selected as control group. All the participants were tested for cytokines (IL-6, IL-10, IL-17A, TNF-α, IFN-γ) and statistically analyzed the relevant experimental data. Results: The levels of IL-6, IL-10, IL-17A, TNF-α and IFN-γ in the infected group after treatment were significantly lower than those before treatment (P<0.05) . The levels of IL-6, IL-10, IL-17A, TNF-α and IFN-γ before and after treatment in the infected group were higher than those in the non-infected group and the control group (P<0.05) . The levels of IL-10, IL-17A, TNF-α and IFN-γ in the infected group were higher than those in the control group, and the difference were statistically significant (P<0.05) . The levels of IL-6, IL-10, IL-17A and IFN-γ in patients with stage III silicosis were higher than those in stage I silicosis in infected group (P<0.05) . The levels of IL-6 and IL-17A in the patients with stage Ⅲ silicosis were higher than those in the patients with stage II silicosis in infected group (P<0.05) . The level of IL-10 in patients with stage II silicosis was higher than that in stage I in infected group (P<0.05) . ROC curve analysis of the indicators for diagnosis of senile silicosis with lower respiratory tract infection and silicosis without lower respiratory tract infection found that IL-6 had the largest AUC (0.910) . And its specifuity and sensithcity were 85.2% and 98.1% respectivehy. Conclusion: The detection of cytokines such as IL-6 and IL-10 has better specificity and higher diagnostic efficiency in the early diagnosis and treatment of elderly patients with silicosis complicated with lower respiratory tract infection. It has good clinical application value and can provide important laboratory evidence for early treatment for clinicians.

Antibacterial Resistance in Lower Respiratory Tract Bacterial Pathogens: A Multicenter Analysis from Turkey

INTRODUCTION

This study aimed to evaluate the etiology of lower respiratory tract infections (LRTIs) and their antibiotic resistance.

METHODOLOGY

Bacterial culture results of LRT samples from 17 hospitals between 2016-2019 were included in the study. All isolates were identified and AST were performed by automated microbiology systems. AST was performed according to EUCAST.

RESULTS

Non-duplicate 30,051 (26,890 HA and 3156 CA) isolates detected as causative pathogen. LRTIs are caused by 85.1% Gram-negative bacterial pathogens and 14.9% Gram-positive. The most common isolates among HA pathogens were Acinetobacter spp. (27.4%), P.aeruginosa (22.2%), K.pneumoniae (17.9%); among CA pathogen S.pneumoniae (19.9%), P. aeruginosa (18.9%), H.influenzae (14.6%). ESBL rate was 62.5% in K.penumoniae; 53.1% in E.coli; 19.1% in Klebsiella spp; 13.9% in Enterobacter spp.; 8.6% in Proteus spp.; 6.3% in Citrobacter spp.; and 4.3% in Serratia spp. Resistance rates to carbapenems and colistin were 92.8% and 12.8% in A baumannii, 39.8% and 7.5% in P.aeruginosa, 47.3% and 18.5% in K.penumoniae. Among staphylococci, 27.3% of S. aureus and 82.4% of CoNS were methicillin resistant. 7.6% of E.faecium and 0.9% of E.faecalis were vancomycin resistant.  Linezolid resistant S. aureus, CoNS, E.faecalis and E.faecium rates were 0.3%, 2.9%, 0.0% and 4.6%. Inducible clindamycin resistant rate was 17.2% in S. aureus 38.2% in CoNS. Non-susceptible S.pneumoniae isolate rate to penicillin was 37.0%. 6.5% of S.maltophilia and 4.4% of B.cepacia isolates were resistant to trimethoprim/sulfamethoxazole.

CONCLUSIONS

Antibiotic resistance was mainly observed among A.baumannii and K.pneumoniae and continuous surveillance of antimicrobial resistance patterns in the management of LRTIs is important.

Respiratory Complications in Children and Adolescents with Human Immunodeficiency Virus

Respiratory complications comprise a large proportion of the burden of mortality and morbidity in children with human immunodeficiency virus (HIV). HIV-associated lower respiratory tract infection (LRTI) has declined in incidence with early diagnosis and use of antiretroviral therapy (ART) but is widespread in areas with limited access to ART. HIV-exposed uninfected infants have a higher risk of LRTI early in life than unexposed infants. Pulmonary tuberculosis (PTB) presenting as acute or chronic disease is common in highly TB endemic areas. Chronic lung disease is common; preceding LRTI, PTB or late initiation of ART are risk factors.

Bordetella pertussis is a common pathogen in infants hospitalized for acute lower respiratory tract infection during the winter season

INTRODUCTION

There is some evidence that Bordetella pertussis (B. pertussis) can co-infect with viral respiratory infections in young infants.

METHODS

B. pertussis infection was studied by culture, polymerase chain reaction (PCR), and loop-mediated isothermal amplification (LAMP) from nasopharyngeal swabs (NPSs) in 49 infants < 12 months of age, who were admitted for lower respiratory tract infections during the winter season. Seven other possible viral pathogens were documented by antigen detection or PCR in NPSs. The clinical feature of infants with mixed infection of B. pertussis and respiratory viruses were examined.

RESULTS

Overall, B. pertussis infection was found in 10 (20.4%) cases, nine were less than 6 months of age and seven were unvaccinated. Viral etiology was found in 41 (84%) cases and pertussis-viral co-infection was present in eight patients, five of whom had mixed infection with respiratory syncytial virus. Only the presence of staccato coughing, cyanosis, and lymphocytosis were significantly different in B. pertussis-positive cases compared with B. pertussis-negative cases. Of the 10 pertussis cases, only the culture-positive cases showed the typical symptoms and laboratory findings of pertussis in addition to virus-associated respiratory symptoms with severe hospital course, whereas cases identified as DNA-positive lacked the characteristics of pertussis and their clinical severities were the same as B. pertussis-negative cases.

CONCLUSION

In the absence of typical paroxysmal cough and lymphocytosis, we should carefully consider diagnosis of pertussis in young children hospitalized for presumed viral respiratory illness according to local epidemiological surveillance.

Multicentric evaluation of BioFire FilmArray Pneumonia Panel for rapid bacteriological documentation of pneumonia

OBJECTIVES

To evaluate performances of the rapid multiplex PCR assay BioFire FilmArray Pneumonia Panel (FA-PP) for detection of bacterial pathogens and antibiotic resistance genes in sputum, endotracheal aspirate (ETA) and bronchoalveolar lavage (BAL) specimens.

METHODS

This prospective observational study was conducted in 11 French university hospitals (July to December 2018) and assessed performance of FA-PP by comparison with routine conventional methods.

RESULTS

A total of 515 respiratory specimens were studied, including 58 sputa, 217 ETA and 240 BAL. The FA-PP detected at least one pathogen in 384 specimens, yielding an overall positivity rate of 74.6% (384/515). Of them, 353 (68.5%) specimens were positive for typical bacteria while eight atypical bacteria and 42 resistance genes were found. While identifying most bacterial pathogens isolated by culture (374/396, 94.4%), the FA-PP detected 294 additional species in 37.7% (194/515) of specimens. The FA-PP demonstrated positive percentage agreement and negative percentage agreement values of 94.4% (95% CI 91.7%-96.5%) and 96.0% (95% CI 95.5%-96.4%), respectively, when compared with culture. Of FA-PP false-negative results, 67.6% (46/68) corresponded to bacterial species not included in the panel. At the same semi-quantification level (in DNA copies/mL for FA-PP versus in CFU/mL for culture), the concordance rate was 43.4% (142/327) for culture-positive specimens with FA-PP reporting higher semi-quantification of ≥1 log₁₀ in 48.6% (159/327) of cases. Interestingly, 90.1% of detected bacteria with ≥10⁶ DNA copies/mL grew significantly in culture.

CONCLUSIONS

FA-PP is a simple and rapid molecular test that could complement routine conventional methods for improvement of diagnosis accuracy of pneumonia.

Lactate dehydrogenase isoenzymes in patients with acute exacerbation of chronic obstructive pulmonary disease: An exploratory cross-sectional study

We aimed to evaluate differences in serum lactate dehydrogenase (LDH) isoenzymes between patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and other lower respiratory tract infections (LRTIs). Based on self-reported COPD diagnosis, 71 participants were divided into AECOPD (n = 38, 29 males, mean age 70.5 years) and LRTI (n = 33, 12 males, mean age 70.4 years) groups. Information on demographics, comorbidities, and COPD severity markers, as well as arterial blood gases and laboratory data were collected, while serum LDH electrophoresis was performed to examine the LDH isoenzymes. Adjusting for sex, age, comorbidities, degree of hypoxemia, inflammation markers, muscle and myocardial enzymes, and total serum LDH, the mean differences (95 % confidence intervals) in the ratios of serum LDH isoenzymes to total serum LDH between groups (LDHx_AECOPD - LDHx_LRTI) were statistically significant for LDH1 [4.9 (1.4 to 8.3)], LDH2 [3.0 (0.1 to 5.8)], LDH3 [-4.3 (-6.3 to -2.3)], and LDH4 [-3.2 (-4.9 to -1.5)]. A sum of LDH3 and LDH4 ratios below 29 % had the highest discriminative ability to classify a subject in the AECOPD group (AUC 0.841, sensitivity 76 %, specificity 87 %). Aerobic metabolic adaptive mechanisms in respiratory muscles during AECOPD could explain the above differences.

Thoracic imaging of coronavirus disease 2019 (COVID-19) in children: a series of 91 cases

BACKGROUND

Pulmonary infection with SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus 2; COVID-19) has rapidly spread worldwide to become a global pandemic.

OBJECTIVE

To collect paediatric COVID-19 cases worldwide and to summarize both clinical and imaging findings in children who tested positive on polymerase chain reaction testing for SARS-CoV-2.

MATERIALS AND METHODS

Data were collected by completion of a standardised case report form submitted to the office of the European Society of Paediatric Radiology from March 12 to April 8, 2020. Chest imaging findings in children younger than 18 years old who tested positive on polymerase chain reaction testing for SARS-CoV-2 were included. Representative imaging studies were evaluated by multiple senior paediatric radiologists from this group with expertise in paediatric chest imaging.

RESULTS

Ninety-one children were included (49 males; median age: 6.1 years, interquartile range: 1.0 to 13.0 years, range: 9 days-17 years). Most had mild symptoms, mostly fever and cough, and one-third had coexisting medical conditions. Eleven percent of children presented with severe symptoms and required intensive unit care. Chest radiographs were available in 89% of patients and 10% of them were normal. Abnormal chest radiographs showed mainly perihilar bronchial wall thickening (58%) and/or airspace consolidation (35%). Computed tomography (CT) scans were available in 26% of cases, with the most common abnormality being ground glass opacities (88%) and/or airspace consolidation (58%). Tree in bud opacities were seen in 6 of 24 CTs (25%). Lung ultrasound and chest magnetic resonance imaging were rarely utilized.

CONCLUSION

It seems unnecessary to perform chest imaging in children to diagnose COVID-19. Chest radiography can be used in symptomatic children to assess airway infection or pneumonia. CT should be reserved for when there is clinical concern to assess for possible complications, especially in children with coexisting medical conditions.