Bronchoscopy-guided antimicrobial therapy for cystic fibrosis.

BACKGROUND: Early diagnosis and treatment of lower respiratory tract infections is the mainstay of management of lung disease in cystic fibrosis (CF). When sputum samples are unavailable, diagnosis relies mainly on cultures from oropharyngeal specimens; however, there are concerns about whether this approach is sensitive enough to identify lower respiratory organisms. Bronchoscopy and related procedures such as bronchoalveolar lavage (BAL) are invasive but allow the collection of lower respiratory specimens from non-sputum producers. Cultures of bronchoscopic specimens provide a higher yield of organisms compared to those from oropharyngeal specimens. Regular use of bronchoscopy and related procedures may increase the accuracy of diagnosis of lower respiratory tract infections and improve the selection of antimicrobials, which may lead to clinical benefits. This is an update of a previous review that was first published in 2013 and was updated in 2016 and in 2018. OBJECTIVES: To evaluate the use of bronchoscopy-guided (also known as bronchoscopy-directed) antimicrobial therapy in the management of lung infection in adults and children with cystic fibrosis. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched three registries of ongoing studies and the reference lists of relevant articles and reviews. The date of the most recent searches was 1 November 2023. SELECTION CRITERIA: We included randomised controlled studies involving people of any age with CF that compared the outcomes of antimicrobial therapies guided by the results of bronchoscopy (and related procedures) versus those guided by any other type of sampling (e.g. cultures from sputum, throat swab and cough swab). DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed their risk of bias and extracted data. We contacted study investigators for further information when required. We assessed the certainty of the evidence using the GRADE criteria. MAIN RESULTS: We included two studies in this updated review. One study enrolled 170 infants under six months of age who had been diagnosed with CF through newborn screening. Participants were followed until they were five years old, and data were available for 157 children. The study compared outcomes for pulmonary exacerbations following treatment directed by BAL versus standard treatment based on clinical features and oropharyngeal cultures. The second study enrolled 30 children with CF aged between five and 18 years and randomised participants to receive treatment based on microbiological results of BAL triggered by an increase in lung clearance index (LCI) of at least one unit above baseline or to receive standard treatment based on microbiological results of oropharyngeal samples collected when participants were symptomatic. We judged both studies to have a low risk of bias across most domains, although the risk of bias for allocation concealment and selective reporting was unclear in the smaller study. In the larger study, the statistical power to detect a significant difference in the prevalence of Pseudomonas aeruginosa was low because Pseudomonas aeruginosa isolation in BAL samples at five years of age in both groups were much lower than the expected rate that was used for the power calculation. We graded the certainty of evidence for the key outcomes as low, other than for high-resolution computed tomography scoring and cost-of-care analysis, which we graded as moderate certainty. Both studies reported similar outcomes, but meta-analysis was not possible due to different ways of measuring the outcomes and different indications for the use of BAL. Whether antimicrobial therapy is directed by the use of BAL or standard care may make little or no difference in lung function z scores after two years (n = 29) as measured by the change from baseline in LCI and forced expiratory volume in one second (FEV1) (low-certainty evidence). At five years, the larger study found little or no difference between groups in absolute FEV1 z score or forced vital capacity (FVC) (low-certainty evidence). BAL-directed therapy probably makes little or no difference to any measure of chest scores assessed by computed tomography (CT) scan at either two or five years (different measures used in the two studies; moderate-certainty evidence). BAL-directed therapy may make little or no difference in nutritional parameters or in the number of positive isolates of P aeruginosa per participant per year, but may lead to more hospitalisations per year (1 study, 157 participants; low-certainty evidence). There is probably no difference in average cost of care per participant (either for hospitalisations or total costs) at five years between BAL-directed therapy and standard care (1 study, 157 participants; moderate-certainty evidence). We found no difference in health-related quality of life between BAL-directed therapy and standard care at either two or five years, and the larger study found no difference in the number of isolates of Pseudomonas aeruginosa per child per year. The eradication rate following one or two courses of eradication treatment and the number of pulmonary exacerbations were comparable in the two groups. Mild adverse events, when reported, were generally well tolerated. The most common adverse event reported was transient worsening of cough after 29% of procedures. Significant clinical deterioration was documented during or within 24 hours of BAL in 4.8% of procedures. AUTHORS' CONCLUSIONS: This review, limited to two well-designed randomised controlled studies, shows no evidence to support the routine use of BAL for the diagnosis and management of pulmonary infection in preschool children with CF compared to the standard practice of providing treatment based on results of oropharyngeal culture and clinical symptoms. No evidence is available for adults.

Impact of lumacaftor/ivacaftor on the bacterial and fungal respiratory pathogens in cystic fibrosis: a prospective multicenter cohort study in Sweden.

BACKGROUND: A significant decline in pulmonary exacerbation rates has been reported in CF patients homozygous for F508del treated with lumacaftor/ivacaftor. However, it is still unclear whether this reduction reflects a diminished microbiological burden. OBJECTIVES: The aim of this study was to determine the impact of lumacaftor/ivacaftor on the bacterial and fungal burden. DESIGN: The study is a prospective multicenter cohort study including 132 CF patients homozygous for F508del treated with lumacaftor/ivacaftor. METHODS: Clinical parameters as well as bacterial and fungal outcomes 1 year after initiation of lumacaftor/ivacaftor were compared to data from 2 years prior to initiation of the treatment. Changes in the slope of the outcomes before and after the onset of treatment were assessed. RESULTS: Lung function measured as ppFEV1 (p < 0.001), body mass index (BMI) in adults (p < 0.001), and BMI z-score in children (p = 0.007) were improved after initiation of lumacaftor/ivacaftor. In addition, the slope of the prevalence of Streptococcus pneumoniae (p = 0.007) and Stenotrophomonas maltophilia (p < 0.001) shifted from positive to negative, that is, became less prevalent, 1 year after treatment, while the slope for Candida albicans (p = 0.009), Penicillium spp (p = 0.026), and Scedosporium apiospermum (p < 0.001) shifted from negative to positive. CONCLUSION: The current study showed a significant improvement in clinical parameters and a reduction of some of CF respiratory microorganisms 1 year after starting with lumacaftor/ivacaftor. However, no significant changes were observed for Pseudomonas aeruginosa, Staphylococcus aureus, or Aspergillus fumigatus, key pathogens in the CF context.

Inhaled antibiotics: A promising drug delivery strategies for efficient treatment of lower respiratory tract infections (LRTIs) associated with antibiotic resistant biofilm-dwelling and intracellular bacterial pathogens.

Antibiotic-resistant bacteria associated with LRTIs are frequently associated with inefficient treatment outcomes. Antibiotic-resistant Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, and Staphylococcus aureus, infections are strongly associated with pulmonary exacerbations and require frequent hospital admissions, usually following failed management in the community. These bacteria are difficult to treat as they demonstrate multiple adaptational mechanisms including biofilm formation to resist antibiotic threats. Currently, many patients with the genetic disease cystic fibrosis (CF), non-CF bronchiectasis (NCFB) and chronic obstructive pulmonary disease (COPD) experience exacerbations of their lung disease and require high doses of systemically administered antibiotics to achieve meaningful clinical effects, but even with high systemic doses penetration of antibiotic into the site of infection within the lung is suboptimal. Pulmonary drug delivery technology that reliably deliver antibacterials directly into the infected cells of the lungs and penetrate bacterial biofilms to provide therapeutic doses with a greatly reduced risk of systemic adverse effects. Inhaled liposomal-packaged antibiotic with biofilm-dissolving drugs offer the opportunity for targeted, and highly effective antibacterial therapeutics in the lungs. Although the challenges with development of some inhaled antibiotics and their clinicals trials have been studied; however, only few inhaled products are available on market. This review addresses the current treatment challenges of antibiotic-resistant bacteria in the lung with some clinical outcomes and provides future directions with innovative ideas on new inhaled formulations and delivery technology that promise enhanced killing of antibiotic-resistant biofilm-dwelling bacteria.

Polyoxometalate exerts broad-spectrum activity against human respiratory viruses hampering viral entry.

Human respiratory viruses have an enormous impact on national health systems, societies, and economy due to the rapid airborne transmission and epidemic spread of such pathogens, while effective specific antiviral drugs to counteract infections are still lacking. Here, we identified two Keggin-type polyoxometalates (POMs), [TiW11CoO40]8- (TiW11Co) and [Ti2PW10O40]7- (Ti2PW10), endowed with broad-spectrum activity against enveloped and non-enveloped human respiratory viruses, i.e., coronavirus (HCoV-OC43), rhinovirus (HRV-A1), respiratory syncytial virus (RSV-A2), and adenovirus (AdV-5). Ti2PW10 showed highly favorable selectivity indexes against all tested viruses (SIs >700), and its antiviral potential was further investigated against human coronaviruses and rhinoviruses. This POM was found to inhibit replication of multiple HCoV and HRV strains, in different cell systems. Ti2PW10 did not affect virus binding or intracellular viral replication, but selectively inhibited the viral entry. Serial passaging of virus in presence of the POM revealed a high barrier to development of Ti2PW10-resistant variants of HRV-A1 or HCoV-OC43. Moreover, Ti2PW10 was able to inhibit HRV-A1 production in a 3D model of the human nasal epithelium and, importantly, the antiviral treatment did not determine cytotoxicity or tissue damage. A mucoadhesive thermosensitive in situ hydrogel formulation for nasal delivery was also developed for Ti2PW10. Overall, good biocompatibility on cell lines and human nasal epithelia, broad-spectrum activity, and absence of antiviral resistance development reveal the potential of Ti2PW10 as an antiviral candidate for the development of a treatment of acute respiratory viral diseases, warranting further studies to identify the specific target/s of the polyanion and assess its clinical potential.

Prognostic factors and prediction models for hospitalisation and all-cause mortality in adults presenting to primary care with a lower respiratory tract infection: a systematic review.

OBJECTIVE: To identify and synthesise relevant existing prognostic factors (PF) and prediction models (PM) for hospitalisation and all-cause mortality within 90 days in primary care patients with acute lower respiratory tract infections (LRTI). DESIGN: Systematic review. METHODS: Systematic searches of MEDLINE, Embase and the Cochrane Library were performed. All PF and PM studies on the risk of hospitalisation or all-cause mortality within 90 days in adult primary care LRTI patients were included. The risk of bias was assessed using the Quality in Prognostic Studies tool and Prediction Model Risk Of Bias Assessment Tool tools for PF and PM studies, respectively. The results of included PF and PM studies were descriptively summarised. RESULTS: Of 2799 unique records identified, 16 were included: 9 PF studies, 6 PM studies and 1 combination of both. The risk of bias was judged high for all studies, mainly due to limitations in the analysis domain. Based on reported multivariable associations in PF studies, increasing age, sex, current smoking, diabetes, a history of stroke, cancer or heart failure, previous hospitalisation, influenza vaccination (negative association), current use of systemic corticosteroids, recent antibiotic use, respiratory rate ≥25/min and diagnosis of pneumonia were identified as most promising candidate predictors. One newly developed PM was externally validated (c statistic 0.74, 95% CI 0.71 to 0.78) whereas the previously hospital-derived CRB-65 was externally validated in primary care in five studies (c statistic ranging from 0.72 (95% CI 0.63 to 0.81) to 0.79 (95% CI 0.65 to 0.92)). None of the PM studies reported measures of model calibration. CONCLUSIONS: Implementation of existing models for individualised risk prediction of 90-day hospitalisation or mortality in primary care LRTI patients in everyday practice is hampered by incomplete assessment of model performance. The identified candidate predictors provide useful information for clinicians and warrant consideration when developing or updating PMs using state-of-the-art development and validation techniques. PROSPERO REGISTRATION NUMBER: CRD42022341233.

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.

Emerging therapies and respiratory infections: Focus on the impact of immunosuppressants and immunotherapies.

Host defences to infection are based upon an integrated system of physical and biochemical barriers, innate and adaptive immunity. Weakness in any of these defensive elements leads to increased susceptibility to specific pathogens. Understanding how medical therapies disrupt host defences is key to the successful prevention, diagnosis and management of respiratory infection in the immunocompromised host.

Clinical evaluation of pediatric patients with recurrent respiratory papillomatosis.: A longitudinal study at a Saudi Arabian tertiary care center.

OBJECTIVES: To study the clinical evaluation of recurrent respiratory papillomatosis (RRP) patients and the factors associated with the improvement in the Derkay's score as a measure of disease severity. METHODS: A retrospective cohort that included all juvenile RRP patients who were admitted to King Abdulaziz University Hospital, Riyadh, Saudi Arabia, between September 2015 and June 2022 and underwent surgical debulking. RESULTS: A total of 16 patients were eligible to join our study. Among them, 7 patients were males. Hoarseness of voice was the most frequent symptom. The median period of the follow-up was 56 months. Complete remission was achieved in 31.3%. The univariate linear regression model revealed that the cidofovir-treated patients had a significant reduction in the change value of Derkay's score compared to those without treatment (regression coefficient= -5.83, 95% confidence interval [CI]: [-11.5 to -0.143], p=0.045). Also, the increased first Derkay's score decreased the change value and subsequently increased the improvement chance of the disease (regression coefficient= -0.424, 95% CI: [-0.764 to -0.083], p=0.018). However, in the multivariate regression model, both variables showed non-significant results. CONCLUSION: cidofovir treatment and higher Derkay's scores affected the disease improvement.

Inhaled dry powder liposomal azithromycin for treatment of chronic lower respiratory tract infection.

A dry powder inhaled liposomal azithromycin formulation was developed for the treatment of chronic respiratory diseases such as cystic fibrosis and bronchiectasis. Key properties including liposome size, charge and encapsulation efficiency powder size, shape, glass transition temperature (Tg), water content and in vitro respiratory deposition were determined. Antimicrobial activity against cystic fibrosis (CF) respiratory pathogens was determined by MIC, MBC and biofilm assays. Cytotoxicity and cellular uptake studies were performed using A549 cells. The average liposome size was 105 nm, charge was 55 mV and encapsulation efficiency was 75 %. The mean powder particle size d[v,50] of 4.54 µm and Mass Median Aerodynamic Diameter (MMAD) was 5.23 µm with a mean Tg of 76˚C and water content of 2.1 %. These excellent physicochemical characteristics were maintained over one year. Liposomal loaded azithromycin demonstrated enhanced activity against P. aeruginosa clinical isolates grown in biofilm. The formulation was rapidly delivered into bacterial cells with > 75 % uptake in 1 h. Rapid uptake into A549 cells via a cholesterol-dependent endocytosis pathway with no cytotoxic effects apparent. These data demonstrate that this formulation could offer benefits over current treatment regimens for people with chronic respiratory infection.

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.

Novel Approaches to Multidrug-Resistant Infections in Cystic Fibrosis.

Patients with cystic fibrosis (CF) often develop respiratory tract infections with pathogenic multidrug-resistant organisms (MDROs) such as methicillin-resistant Staphylococcus aureus, and a variety of gram-negative organisms that include Pseudomonas aeruginosa, Burkholderia sp., Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and nontuberculous mycobacteria (NTM). Despite the introduction of new therapies to address underlying cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction, MDRO infections remain a problem and novel antimicrobial interventions are still needed. Therapeutic approaches include improving the efficacy of existing drugs by adjusting the dose based on differences in CF patient pharmacokinetics/pharmacodynamics, the development of inhaled formulations to reduce systemic adverse events, and the use of newer beta-lactam/beta-lactamase combinations. Alternative innovative therapeutic approaches include the use of gallium and bacteriophages to treat MDRO pulmonary infections including those with extreme antibiotic resistance. However, additional clinical trials are required to determine the optimal dosing and efficacy of these different strategies and to identify patients with CF most likely to benefit from these new treatment options.

Prevalence and Clinical Impact of Respiratory Viral Infections from the STOP2 Study of Cystic Fibrosis Pulmonary Exacerbations.

Rationale: Rates of viral respiratory infection (VRI) are similar in people with cystic fibrosis (CF) and the general population; however, the associations between VRI and CF pulmonary exacerbations (PEx) require further elucidation.Objectives: To determine VRI prevalence during CF PEx and evaluate associations between VRI, clinical presentation, and treatment response.Methods: The STOP2 (Standardized Treatment of Pulmonary Exacerbations II) study was a multicenter randomized trial to evaluate different durations of intravenous antibiotic therapy for PEx. In this ancillary study, participant sputum samples from up to three study visits were tested for respiratory viruses using multiplex polymerase chain reactions. Baselines and treatment-associated changes in mean lung function (percent predicted forced expiratory volume in 1 s), respiratory symptoms (Chronic Respiratory Infection Symptom Score), weight, and C-reactive protein were compared as a function of virus detection. Odds of PEx retreatment within 30 days and future PEx hazard were modeled by logistic and Cox proportional hazards regression, respectively.Results: A total of 1,254 sputum samples from 621 study participants were analyzed. One or more respiratory viruses were detected in sputum samples from 245 participants (39.5%). Virus-positive participants were more likely to be receiving CF transmembrane conductance regulator modulator therapy (45% vs. 34%) and/or chronic azithromycin therapy (54% vs. 44%) and more likely to have received treatment for nontuberculous Mycobacterium infection in the preceding 2 years (7% vs. 3%). At study visit 1, virus-positive participants were more symptomatic (mean Chronic Respiratory Infection Symptom Score, 53.8 vs. 51.1), had evidence of greater systemic inflammation (log10 C-reactive protein concentration, 1.32 log10 mg/L vs. 1.23 log10 mg/L), and had a greater drop in percent predicted forced expiratory volume in 1 second from the prior 6-month baseline (5.8 vs. 3.6). Virus positivity was associated with reduced risk of future PEx (hazard ratio, 0.82; 95% confidence interval, 0.69-0.99; P = 0.034) and longer median time to next PEx (255 d vs. 172 d; P = 0.021) compared with virus negativity.Conclusions: More than one-third of STOP2 participants treated for a PEx had a positive test result for a respiratory virus with more symptomatic initial presentation compared with virus-negative participants, but favorable long-term outcomes. More refined phenotyping of PEx, taking VRIs into account, may aid in optimizing personalized management of PEx.Clinical trial registered with www.clinicaltrials.gov (NCT02781610).

Efficacy of Systemic Bevacizumab for Recurrent Respiratory Papillomatosis with Pulmonary Involvement.

OBJECTIVES: Pulmonary papillomatosis is a rare but severe manifestation of recurrent respiratory papillomatosis (RRP). Efficacy data of systemic bevacizumab for pulmonary RRP are limited. This study's objective was to characterize disease response of pulmonary RRP to systemic bevacizumab. METHODS: A retrospective review was performed to identify patients with pulmonary RRP seen at three medical institutions. Clinical symptoms, CT findings, and disease response were compared before and after initiation of systemic bevacizumab therapy. Disease response was categorized as complete response, partial response, stabilization, or progression for each subsite involved by papilloma. RESULTS: Of the 12 pulmonary RRP patients treated with systemic bevacizumab, 4 (33.3%) were male, and 11 (91.7%) were juvenile-onset RRP patients. All presented with laryngeal, tracheal, and pulmonary RRP. The median (range) age at first bevacizumab infusion was 48.1 (19.5-70.2) years. Progression to pulmonary malignancy was identified in 3 (25.0%) patients, 2 before initiation of and 1 after complete cessation of bevacizumab therapy. Clinical symptoms such as dyspnea (75.0% vs. 25.0%; p = 0.01) and dysphagia and/or odynophagia (33.3 vs. 0.0%; p = 0.03) were significantly decreased following bevacizumab therapy. Compared with pre-treatment baseline, 9 (75.0%) patients experienced a stable-to-partial response in the lungs to systemic bevacizumab, and 10 (83.3%) experienced partial-to-complete responses in the larynx and trachea. CONCLUSION: Systemic bevacizumab is effective in stabilizing progression in even the most severe cases of RRP, with both a dramatic reduction in laryngeal and tracheal disease as well as a stable-to-partial response of pulmonary involvement in a majority of patients. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:577-581, 2024.

Why do some Children Get Sick with Recurrent Respiratory Infections?

Respiratory tract infections (RTI) represent a frequent condition, particularly among preschool children, with an important burden on the affected children and their families. It has been estimated that recurrent RTIs affect up to 25% of children during the first 4 years of life. These infections are mainly caused by viruses and are generally self-limiting. Social and environmental factors have been studied in determining the incidence of recurrent RTIs and the mostly recognized are precocious day care attendance, tobacco exposure and pollution. Primary immune defects, local anatomical factors, and genetic disorders such as primary ciliary dyskinesia or cystic fibrosis, may be also involved in recurrent RTIs of a subgroup of children, typically characterized by more severe and chronic symptoms. However, there is increasing awareness that RTIs have a complex pathophysiology and that some underrecognized factors, including genetic susceptibility to infections, low levels of some micronutrients, and respiratory microbiota might shape the probability for the child to develop RTIs. The sum (i.e. the number) of these factors may help in explaining why some children get sick for RTIs whilst other not. In some children iatrogenic factors, including improper use of antibiotics and NSAIDS or glucocorticoids might also aggravate this condition, further weakening the host's immune response and the possibly of establishing a "vicious circle". The present review aims to focus on several possible factors involved in influencing RTIs and to propose a unifying hypothesis on pathophysiological mechanisms of unexplained recurrent RTIs in children.

Upper and/or Lower Respiratory Tract Infection Caused by Human Metapneumovirus After Allogeneic Hematopoietic Stem Cell Transplantation.

BACKGROUND: Human metapneumovirus (hMPV) epidemiology, clinical characteristics and risk factors for poor outcome after allogeneic stem cell transplantation (allo-HCT) remain a poorly investigated area. METHODS: This retrospective multicenter cohort study examined the epidemiology, clinical characteristics, and risk factors for poor outcomes associated with human metapneumovirus (hMPV) infections in recipients of allo-HCT. RESULTS: We included 428 allo-HCT recipients who developed 438 hMPV infection episodes between January 2012 and January 2019. Most recipients were adults (93%). hMPV infections were diagnosed at a median of 373 days after allo-HCT. The infections were categorized as upper respiratory tract disease (URTD) or lower respiratory tract disease (LRTD), with 60% and 40% of cases, respectively. Patients with hMPV LRTD experienced the infection earlier in the transplant course and had higher rates of lymphopenia, neutropenia, corticosteroid use, and ribavirin therapy. Multivariate analysis identified lymphopenia and corticosteroid use (>30 mg/d) as independent risk factors for LRTD occurrence. The overall mortality at day 30 after hMPV detection was 2% for URTD, 12% for possible LRTD, and 21% for proven LRTD. Lymphopenia was the only independent risk factor associated with day 30 mortality in LRTD cases. CONCLUSIONS: These findings highlight the significance of lymphopenia and corticosteroid use in the development and severity of hMPV infections after allo-HCT, with lymphopenia being a predictor of higher mortality in LRTD cases.

[Meta-analysis and trial sequential analysis of Chaihuang Granules in treatment of upper respiratory tract infection in children].

This study aimed to evaluate the efficacy and safety of Chaihuang Granules in the treatment of upper respiratory tract infection in children. The databases such as CNKI, Wanfang, VIP, SinoMed, Cochrane Library, PubMed, EMbase, Web of Science, Chinese Clinical Trial Registry, and ClinicalTrials.gov were searched for randomized controlled trial(RCT) of Chaihuang Granules for the treatment of upper respiratory tract infection in children, and supplemented by manual searching of gray literature. Two investigators independently screened the literature, extracted data, and assessed the methodological quality. Meta-analysis was performed using RevMan 5.4 software, trial sequential analysis was conducted using TSA 0.9.5.10 Beta software, and evidence quality evaluation was carried out using GRADE profiler 3.6.1 software. Eighteen RCTs involving 2 459 patients(1 262 in the treatment group and 1 197 in the control group) were included. Meta-analysis showed that compared with conventional therapy alone, Chaihuang Granules significantly improved the total effective rate(RR=1.18, 95%CI[1.15, 1.22], P<0.000 01), reduced the disappearance time of symptoms/signs(MD=-1.39, 95%CI[-1.66,-1.12], P<0.000 01), improved cytokine levels(MD=-2.40, 95%CI[-3.80,-1.00], P=0.000 8), improved humoral immune levels(MD=0.75, 95%CI[0.60, 0.90], P<0.000 01), and reduced the recurrence rate(MD=-2.11, 95%CI[-2.98,-1.25], P<0.000 01). However, the incidence of adverse reactions was not increased(RR=0.94, 95%CI[0.59, 1.49], P=0.78). Subgroup analysis showed that:(1) both Chaihuang Granules used alone(RR=1.19, 95%CI[1.11, 1.27], P<0.000 01) and in combination with other therapies(RR=1.18, 95%CI[1.14, 1.22], P<0.000 01) effectively improved the total effective rate.(2) In terms of symptoms/signs disappearance time, Chaihuang Granules effectively reduced the duration of fever(MD=-1.18, 95%CI[-1.78,-0.58], P=0.000 1), cough with sputum(MD=-1.82, 95%CI[-2.38,-1.25], P<0.000 01), cough(MD=-1.31, 95%CI[-1.89,-0.74], P<0.000 01), sore throat(MD=-1.57, 95%CI[-2.25,-0.89], P<0.000 01), and lung rales(MD=-1.49, 95%CI[-2.06,-0.92], P<0.000 01).(3) Regarding cytokine levels, Chaihuang Gra-nules effectively improved the levels of interleukin(IL)-2(MD=-0.94, 95%CI[-1.16,-0.72], P<0.000 01), IL-6(MD=-4.71, 95%CI[-6.39,-3.03], P<0.000 01), and tumor necrosis factor-α(TNF-α)(MD=-2.07, 95%CI[-2.43,-1.71], P<0.000 01).(4) In terms of cellular immune levels, Chaihuang Granules effectively improved the levels of CD3~+(MD=4.11, 95%CI[1.53, 6.69], P=0.002), CD4~+(MD=4.21, 95%CI[1.69, 6.73], P=0.001), CD8~+(MD=-2.65, 95%CI[-3.93,-1.37], P<0.000 1), and CD4~+/CD8~+(MD=0.25, 95%CI[0.14, 0.37], P<0.000 1).(5) In terms of humoral immune levels, Chaihuang Granules effectively improved the levels of IgA(MD=0.44, 95%CI[0.23, 0.64], P<0.000 1), IgM(MD=0.31, 95%CI[0.15, 0.46], P=0.000 1), and IgG(MD=2.02, 95%CI[1.60, 2.43], P<0.000 01). Trial sequential analysis showed that the cumulative Z-curve of the total effective rate crossed the boundary value, further confirming its clinical efficacy. The GRADE evidence quality evaluation showed that the evidence quality of the above outcome indicators was low or very low, and the recommendation strength was weak. Compared to conventional therapy alone, Chaihuang Granules can effectively improve the total effective rate of treatment, alle-viate symptoms and signs of upper respiratory tract infection in children, improve inflammatory conditions, enhance immune function, and reduce the recurrence rate. Due to the limited quality of the included studies, high-quality RCT is still needed to provide evidence support for the above conclusions.

Utility of Respiratory Pathogen Panels in the Outpatient Oncology Setting.

Oncology patients presenting for outpatient evaluation of a respiratory tract infection (RTI) are often tested for a variety of viruses with a respiratory pathogen panel (RPP) in addition to influenza and SARS-CoV-2. This triad of testing is expensive and uncomfortable because it requires 2 nasal swabs. Little evidence supports the use of an RPP in outpatient settings, but it is routinely ordered. This retrospective chart review analyzed 183 RPPs performed at Jefferson between April 2020 and November 2021 in outpatient oncology patients presenting with RTI. Data collected included patient demographics, symptoms, and exam findings at time of RPP, additional testing completed, results of RPP, antibiotic and antiviral use before and after RPP results, and patient outcomes 30 days after RPP. Descriptive statistics were calculated. Of the 183 RPPs analyzed, 16.9% (31) were positive for at least 1 respiratory virus. Fifty-two patients (28.4%) started antibiotics before results of the RPP. Of those, 2 patients (3.8%) had a change in antibiotic plan after RPP results returned. Zero patients were started on antiviral medication before results of the RPP. One patient started antiviral treatment after RPP results returned. In total, only 3 patients (1.6%) had an RPP-driven change in medication management. This study suggests limited utility in use of RPPs for oncology patients presenting to the office with RTI symptoms. Targeted testing with a single nasal swab for influenza, RSV, and SARS-CoV-2 may be more clinically relevant. The authors hope to use these data to implement a quality improvement initiative to reduce RPP utilization in this population.

The potential clinical value of pairing procalcitonin and lung ultrasonography to guide antibiotic therapy in patients with community-acquired pneumonia: a narrative review.

INTRODUCTION: Lower respiratory tract infections (LRTIs) are among the most frequent infections and are prone to inappropriate antibiotic treatments. This results from a limited accuracy of diagnostic tools in identifying bacterial pneumonia. Lung ultrasound (LUS) has excellent sensitivity and specificity in diagnosing pneumonia. Additionally, elevated procalcitonin (PCT) levels correlate with an increased likelihood of bacterial infection. LUS and PCT appear to be complementary in identifying patients with bacterial pneumonia who are likely to benefit from antibiotics. AREAS COVERED: This narrative review aims to summarize the current evidence for LUS to diagnose pneumonia, for PCT to guide antibiotic therapy and the clinical value of pairing both tools. EXPERT OPINION: LUS has excellent diagnostic accuracy for pneumonia in different settings, regardless of the examiner's experience. PCT guidance safely reduces antibiotic prescription in LRTIs. The combination of both tools has demonstrated an enhanced accuracy in the diagnosis of pneumonia, including CAP in the ED and VAP in the ICU, but randomized controlled studies need to validate the clinical impact of a combined approach.

[Use of antibiotics, in a pediatric hospital, for respiratory infection and diarrheal disease]. / Uso de antibióticos, en hospital pediátrico, para infección respiratoria y enfermedad diarreica.

Background: The World Health Organization (WHO) reports an increasing unjustified use of antibiotics in the treatment of Acute Respiratory Infections (ARI) and Acute Diarrheal Diseases (ADD) in children under five years of age. This has generated problems such as polypharmacy and the inappropriate use of antibiotics; characterized by incorrect dosage, use in viral infections, prescription inconsistent with clinical guidelines. Objective: To analyze the prescription of antibiotics, their diagnostic-therapeutic congruence, as well as the correct filling of the medical prescription, in a tertiary level hospital in Mexico. Material and methods: Observational, descriptive cross-sectional study. The electronic medical prescriptions made during the period January-December 2017 with a clinical diagnosis of ARI and EDA were analyzed. Results: Of a total of 21,446 boys and girls under five years of age, 10,233 prescriptions were issued for the treatment of ARI and ADD diagnoses. 80% of the prescriptions complied with the items indicated in the electronic file. Conclusions: The prescription of antibiotics showed a prudent use of antibiotics both in the management of acute diarrheal diseases and in the management of acute respiratory diseases. Diagnostic-therapeutic congruence was found in most of the cases in the prescriptions analyzed.

Introducción: la Organización Mundial de Salud (OMS) reporta un creciente uso injustificado de antibióticos en el tratamiento de las infecciones respiratorias agudas (IRA) y las enfermedades diarreicas agudas (EDA) en menores de cinco años de edad. Lo anterior ha generado problemas como la polifarmacia y el uso inapropiado de antibióticos, caracterizado por dosis incorrectas, uso en infecciones virales y prescripción incongruente con las directrices clínicas. Objetivo: analizar la prescripción de antibióticos, su congruencia diagnóstico-terapéutica, así como el correcto llenado de la receta médica, en un hospital de tercer nivel de México. Material y métodos: estudio transversal observacional, descriptivo. Se analizó las recetas médicas electrónicas realizadas durante el periodo enero-diciembre de 2017 con diagnóstico clínico de IRA y EDA. Resultados: de un total de 21,446 niños y niñas menores de cinco años se otorgaron 10, 233 recetas para el tratamiento de los diagnósticos de IRA y EDA. El 80% de las recetas cumplieron con de los rubros indicados en el expediente electrónico. Conclusiones: la prescripción de antibióticos mostró un uso prudente de antibióticos tanto en el manejo de las enferdades diarreicas agudas como en el manejo de las enfermedades respiratorias agudas. Se encontró, en la mayoría de los casos, congruencia diagnóstico-terapéutica en las prescripciones analizadas.