Integrative genetics-metabolomics analysis of infant bronchiolitis-childhood asthma link: A multicenter prospective study

Background

Infants with bronchiolitis are at high risk for developing childhood asthma. While genome-wide association studies suggest common genetic susceptibilities between these conditions, the mechanisms underlying the link remain unclear.

Objective

Through integrated genetics-metabolomics analysis in this high-risk population, we sought to identify genetically driven metabolites associated with asthma development and genetic loci associated with both these metabolites and asthma susceptibility.

Methods

In a multicenter prospective cohort study of infants hospitalized for bronchiolitis, we profiled the nasopharyngeal metabolome and genotyped the whole genome at hospitalization. We identified asthma-related metabolites from 283 measured compounds and conducted metabolite quantitative trait loci (mtQTL) analyses. We further examined the mtQTL associations by testing shared genetic loci for metabolites and asthma using colocalization analysis and the concordance between the loci and known asthma-susceptibility genes.

Results

In 744 infants hospitalized with bronchiolitis, 28 metabolites (e.g., docosapentaenoate [DPA], 1,2-dioleoyl-sn-glycero-3-phosphoglycerol, sphingomyelin) were associated with asthma risk. A total of 349 loci were associated with these metabolites-161 for non-Hispanic white, 120 for non-Hispanic black, and 68 for Hispanics. Of these, there was evidence for 30 shared loci between 16 metabolites and asthma risk (colocalization posterior probability ≥0.5). The significant SNPs within loci were aligned with known asthma-susceptibility genes (e.g., ADORA1, MUC16).

Conclusion

The integrated genetics-metabolomics analysis identified genetically driven metabolites during infancy that are associated with asthma development and genetic loci associated with both these metabolites and asthma susceptibility. Identifying these metabolites and genetic loci should advance research into the functional mechanisms of the infant bronchiolitis-childhood asthma link.

OUP accepted manuscript

Background

Death certificate data can improve our understanding of the mortality burden associated with respiratory syncytial virus (RSV) and influenza.

Methods

We used International Classification of Diseases, Tenth Revision codes listed on death certificates to characterize deaths from 1999 to 2018 as RSV, influenza, and unspecified bronchiolitis. We described the distribution of each cause of death by age, sex, race/ethnicity, place of death, and contributing causes of death.

Results

Over the 20-year study period, RSV, bronchiolitis, and influenza were listed as the underlying causes of death on 932, 1046, and 52 293 death certificates, respectively. Children <1 year of age accounted for 39% of RSV and bronchiolitis deaths, while 72% of influenza deaths were in adults ≥65 years. Children <1 year were more likely to die outside of the hospital from RSV, bronchiolitis, or influenza compared to all causes (P < .01), and black infants had the highest mortality rate for all 3 causes. Most infants dying from RSV did not have a high-risk condition listed on the death certificate. Death certificates captured 20%–60% of estimated excess RSV-attributable mortality in infants and <1% in seniors.

Conclusions

Thorough reporting on death certificates is an important public health goal, especially as new therapeutics become available. Infants had higher odds of dying out of hospital from respiratory pathogens compared to other causes, and race/ethnicity alone did not explain this disparity.

[Spontaneous remission of follicular bronchiolitis with nonspecific interstitial pneumonia: A case report and literature review]

A 41-year-old female patient was admitted in Department of Respiratory and Critical Care Medicine, Peking University Third Hospital because of having cough for a year. Multiple subpleural ground grass and solid nodules could be seen on her CT scan. Four months before admission, she began to experience dry mouth and eyes, blurred vision, finger joints pain, muscle pain and weakness in both lower limbs and weight loss. At the time of admission, the patient's vital signs were normal, no skin rash was seen, breath sounds in both lungs were clear, no rales or wheeze, no deformities in her hands, no redness, swelling, or tenderness in the joints. There was no edema in both lower limbs. Some lab examinations were performed. Tumor markers including squamous cell carcinoma (SCC) antigen, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), Cyfra21-1, pro-gastrin-releasing peptide (proGRP), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) were all normal. The antinuclear antibody, rheumatoid factor, antineutrophil cytoplasmic antibody, anti-dsDNA antibody, anti-Sm antibody, anti-SSA/SSB antibody, anti-ribonucleoprotein (RNP) antibody, anti-Jo-1 antibody, anti-SCL-70 antibody and anti-ribosomal antibody were all negative. The blood IgG level was normal. The blood fungal β-1.3-D glucose, aspergillus galactomannan antigen, sputum bacterial and fungal culture, and sputum smear test for acid-fast staining were all negative. Lung function was normal. Bronchoscopy showed the airways and mucosa were normal. To clarify the diagnosis, she underwent thoracoscopic lung biopsy, the histopathology revealed follicular bronchiolitis (FB) with nonspecific interstitial pneumonia (NSIP). She did not receive any treatment and after 7 months, the lung opacities were spontaneously resolved. After 7 years of follow-up, the opacities in her lung did not relapse. To improve the understanding of FB, a literature research was performed with "follicular bronchiolitis" as the key word in Wanfang, PubMed and Ovid Database. The time interval was from January 2000 to December 2018. Relative articles were retrieved and clinical treatments and prognosis of FB were analyzed. Eighteen articles concerning FB with complete records were included in the literature review. A total of 51 adult patients with FB were reported, including 18 primary FB and 33 secondary FB, and autoimmune disease was the most common underlying cause. Forty-one (80.4%) patients were prescribed with corticosteroids and/or immunosuppressive agents, 6 (11.8%) patients were treated with anti-infective, 5 (9.8%) patients did not receive any treatment. The longest follow-up period was 107 months. Among the 5 patients without any treatment, 1 patients died of metastatic melanoma, the lung opacities were unchanged in 1 patient and getting severe in 3 patients. In conclusion, FB is a rare disease, the treatment and prognosis are controversial. Corticosteroid and immunosuppressive agents could be effective. This case report suggests the possibility of spontaneous remission of FB.

[Spontaneous remission of follicular bronchiolitis with nonspecific interstitial pneumonia: A case report and literature review]

A 41-year-old female patient was admitted in Department of Respiratory and Critical Care Medicine, Peking University Third Hospital because of having cough for a year. Multiple subpleural ground grass and solid nodules could be seen on her CT scan. Four months before admission, she began to experience dry mouth and eyes, blurred vision, finger joints pain, muscle pain and weakness in both lower limbs and weight loss. At the time of admission, the patient's vital signs were normal, no skin rash was seen, breath sounds in both lungs were clear, no rales or wheeze, no deformities in her hands, no redness, swelling, or tenderness in the joints. There was no edema in both lower limbs. Some lab examinations were performed. Tumor markers including squamous cell carcinoma (SCC) antigen, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), Cyfra21-1, pro-gastrin-releasing peptide (proGRP), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) were all normal. The antinuclear antibody, rheumatoid factor, antineutrophil cytoplasmic antibody, anti-dsDNA antibody, anti-Sm antibody, anti-SSA/SSB antibody, anti-ribonucleoprotein (RNP) antibody, anti-Jo-1 antibody, anti-SCL-70 antibody and anti-ribosomal antibody were all negative. The blood IgG level was normal. The blood fungal β-1.3-D glucose, aspergillus galactomannan antigen, sputum bacterial and fungal culture, and sputum smear test for acid-fast staining were all negative. Lung function was normal. Bronchoscopy showed the airways and mucosa were normal. To clarify the diagnosis, she underwent thoracoscopic lung biopsy, the histopathology revealed follicular bronchiolitis (FB) with nonspecific interstitial pneumonia (NSIP). She did not receive any treatment and after 7 months, the lung opacities were spontaneously resolved. After 7 years of follow-up, the opacities in her lung did not relapse. To improve the understanding of FB, a literature research was performed with "follicular bronchiolitis" as the key word in Wanfang, PubMed and Ovid Database. The time interval was from January 2000 to December 2018. Relative articles were retrieved and clinical treatments and prognosis of FB were analyzed. Eighteen articles concerning FB with complete records were included in the literature review. A total of 51 adult patients with FB were reported, including 18 primary FB and 33 secondary FB, and autoimmune disease was the most common underlying cause. Forty-one (80.4%) patients were prescribed with corticosteroids and/or immunosuppressive agents, 6 (11.8%) patients were treated with anti-infective, 5 (9.8%) patients did not receive any treatment. The longest follow-up period was 107 months. Among the 5 patients without any treatment, 1 patients died of metastatic melanoma, the lung opacities were unchanged in 1 patient and getting severe in 3 patients. In conclusion, FB is a rare disease, the treatment and prognosis are controversial. Corticosteroid and immunosuppressive agents could be effective. This case report suggests the possibility of spontaneous remission of FB.

Bronchiectasis in severe asthma and asthmatic components in bronchiectasis

Asthma and bronchiectasis are different diseases; however, differentiating them can be difficult because they share several symptomatic and physiological similarities. Approximately 20% of patients with bronchiectasis have eosinophilic inflammation, 34% show wheezing, and 7-46% have comorbid asthma, although comorbidity with severe asthma may be limited as shown in 3.3% of cases of bronchiectasis. Meanwhile, 25-68% of patients with severe asthma have comorbid bronchiectasis, and at least two phenotypes are present in the accompanying bronchiectasis: eosinophilic bronchiectasis and chronic infectious bronchiolitis/bronchiectasis. Recent studies show that type-2-targeted biologics are effective for eosinophilic bronchiectasis and theoretically effective for some of the remaining cases when used before oral corticosteroids. Further studies are needed to identify treatment strategies for severe asthma with comorbid bronchiectasis and vice versa.

Rhinovirus induced bronchiolitis and ARDS in pregnancy: a case report

A 25-year-old woman in her 30th week of pregnancy presented with a 3-day history of fevers, productive cough and dyspnoea. On presentation she was tachypnoeic, tachycardic and hypoxic. Auscultation of the chest revealed widespread wheeze and crepitations at the right mid-zone. Despite initial treatment with intravenous antibiotics, nebulised bronchodilators and oral corticosteroids, the patient continued to deteriorate and required transfer to intensive care. Serial chest radiographs showed increasing bilateral alveolar densities consistent with acute respiratory distress syndrome (ARDS). The only positive investigation was a nasopharyngeal swab which revealed rhinovirus RNA. With supportive management, the patient made a full recovery and went on to deliver a healthy infant at 36 weeks gestation. This case explores human rhinoviruses-induced ARDS and highlights the clinical and diagnostic challenges posed by pregnancy in the critically unwell patient.

Successful treatment of smouldering Human T cell Leukemia Virus Type1 associated bronchiolitis and alveolar abnormalities with amplified natural killer therapy

In amplified natural killer (ANK) cell immunotherapy, NK cells are extracted from the patient's blood, cultured for enhancing its anticancer effects and amplified before they are returned to the body. Here, we administered ANK therapy to an 81-year-old female patient diagnosed with smouldering human T cell leukaemia virus-associated bronchioloalveolar disorder. After eight sessions of twice-weekly NK cell infusion, the bilateral diffuse granular shadows on a CT scan and the overall respiratory function improved markedly. Later, the patient received outpatient treatment without serious side effects. Thus, ANK therapy may be safe for elderly patients owing to its infrequent side effects.

Hemorrhaging from an Intramedullary Cavernous Malformation Diagnosed Due to Recurrent Pneumonia and Diffuse Aspiration Bronchiolitis

While aspiration pneumonia constitutes the majority of pneumonia cases in the elderly, it remains highly underdiagnosed. We experienced a case of recurrent pneumonia and chronic cough that was later diagnosed as aspiration pneumonia and diffuse aspiration bronchiolitis (DAB) due to recurrent hemorrhaging from an intramedullary cavernous malformation. The patient was finally diagnosed when life-threatening respiratory depression caused emergency attention. This is the first report of hemorrhaging from an intramedullary cavernous malformation diagnosed due to aspiration pneumonia and DAB. These findings highlight the importance of considering aspiration in cases with recurrent pneumonia or chronic cough. The underlying cause may be a life-threatening condition.

Occupational respiratory and skin diseases among workers exposed to metalworking fluids

PURPOSE OF REVIEW

To examine respiratory and skin diseases that occur among workers exposed to metalworking fluids (MWFs) used during machining processes.

RECENT FINDINGS

Five cases of a severe and previously unrecognized lung disease characterized by B-cell bronchiolitis and alveolar ductitis with emphysema (BADE) were identified among workers at a machining facility that used MWFs, although MWF exposure could not be confirmed as the etiology. In the United Kingdom, MWF is now the predominant cause of occupational hypersensitivity pneumonitis (HP). Under continuous conditions associated with respiratory disease outbreaks, over a working lifetime of 45 years, workers exposed to MWF at 0.1 mg/m3 are estimated to have a 45.3% risk of acquiring HP or occupational asthma under outbreak conditions and a 3.0% risk assuming outbreak conditions exist in 5% of MWF environments. In addition to respiratory outcomes, skin diseases such as allergic and irritant contact dermatitis persist as frequent causes of occupational disease following MWF exposure.

SUMMARY

Healthcare providers need to consider MWF exposure as a potential cause for work-related respiratory and skin diseases. Additional work is necessary to more definitively characterize any potential association between MWF exposures and BADE. Medical surveillance should be implemented for workers regularly exposed to MWF.

Readmissions Following Hospitalization for Infection in Children With or Without Medical Complexity

OBJECTIVE

To describe the prevalence and characteristics of infection-related readmissions in children and to identify opportunities for readmission reduction and estimate associated cost savings.

STUDY DESIGN

Retrospective analysis of 380,067 nationally representative index hospitalizations for children using the 2014 Nationwide Readmissions Database. We compared 30-day, all-cause unplanned readmissions and costs across 22 infection categories. We used the Inpatient Essentials database to measure hospital-level readmission rates and to establish readmission benchmarks for individual infections. We then estimated the number of readmissions avoided and costs saved if hospitals achieved the 10th percentile of hospitals' readmission rates (ie, readmission benchmark). All analyses were stratified by the presence/absence of a complex chronic condition (CCC).

RESULTS

The overall 30-day readmission rate was 4.9%. Readmission rates varied substantially across infections and by presence/absence of a CCC (CCC: range, 0%-21.6%; no CCC: range, 1.5%-8.6%). Approximately 42.6% of readmissions (n = 3,576) for children with a CCC and 54.7% of readmissions (n = 5,507) for children without a CCC could have been potentially avoided if hospitals achieved infection-specific benchmark readmission rates, which could result in an estimated savings of $70.8 million and $44.5 million, respectively. Bronchiolitis, pneumonia, and upper respiratory tract infections were among infections with the greatest number of potentially avoidable readmissions and cost savings for children with and without a CCC.

CONCLUSION

Readmissions following hospitalizations for infection in children vary significantly by infection type. To improve hospital resource use for infections, future preventative measures may prioritize children with complex chronic conditions and those with specific diagnoses (eg, respiratory illnesses).

Immediate Effects and Safety of High-Frequency Chest Wall Compression Compared to Airway Clearance Techniques in Non-Hospitalized Infants With Acute Viral Bronchiolitis

BACKGROUND

No studies have investigated the use and safety of high-frequency chest wall compression (HFCWC) for non-hospitalized infants with acute viral bronchiolitis (AVB). The aim of the present study was to evaluate the immediate effects and safety of HFCWC as compared to airway clearance techniques in children with AVB.

METHODS

In this randomized clinical trial in non-hospitalized infants (0-12 months old) with mild to moderate AVB, children were randomized into 2 groups: airway clearance techniques (20 min of prolonged slow expiration and provoked cough) or HFCWC (15 min). A single session was performed and children were evaluated at baseline and at 10 min and 20 min after treatments. Outcomes measures were the Wang severity score, [Formula: see text], sputum wet-weight, and the presence of adverse events.

RESULTS

A total of 91 infant subjects, mean age 7.9 ± 2.6 months, were included. Significant (P = .004) between-group differences were found in the Wang score, which was 0.28 points lower in the airway clearance techniques group. There was a greater increase of infants classified as normal and a greater decrease of those classified as mild according to the Wang score when airway clearance techniques were used compared to the use of HFCWC (P = .009). The sputum wet-weight was lower in subjects treated with the airway clearance techniques (P < .001). Although [Formula: see text]improved in both groups, no differences were found between them. There was also no difference for adverse events, and the majority of children did not present any adverse events after 20 min.

CONCLUSIONS

The use of HFCWC induced similar clinical effects as airway clearance techniques and was safe for non-hospitalized infants with AVB. Both techniques reduced respiratory symptoms and acutely improved [Formula: see text]. (ClinicalTrials.gov: NCT03835936.).

The importance of viral load in the severity of acute bronchiolitis in hospitalized infants

OBJECTIVE

The relationship between viral load and the clinical evolution of bronchiolitis is controversial. Therefore, we aimed to analyze viral loads in infants hospitalized for bronchiolitis.

METHODS

We tested for the presence of human respiratory syncytial virus (HRSV) or human rhinovirus (HRV) using quantitative molecular tests of nasopharyngeal secretions and recorded severity outcomes.

RESULTS

We included 70 infants [49 (70%) HRSV, 9 (13%) HRV and 12 (17%) HRSV+HRV]. There were no differences among the groups according to the outcomes analyzed individually. Clinical scores showed greater severity in the isolated HRSV infection group. A higher isolated HRSV viral load was associated with more prolonged ventilatory support, oxygen therapy, and hospitalization days, even after adjustment for the age and period of nasopharyngeal secretion collection. In the co-infection groups, there was a longer duration of oxygen therapy when the HRSV viral load was predominant. Isolated HRV infection and co-infection with a predominance of HRV were not associated with severity.

CONCLUSION

Higher HRSV viral load in isolated infections and the predominance of HRSV in co-infections, independent of viral load, were associated with greater severity. These results contribute to the development of therapeutic and prophylactic approaches and a greater understanding of the pathophysiology of bronchiolitis.

Typical RSV cough: myth or reality? A diagnostic accuracy study

Respiratory syncytial virus (RSV) is well known for causing a potentially severe course of bronchiolitis in infants. Many paediatric healthcare workers claim to be able to diagnose RSV based on cough sound, which was evaluated in this study. Parents of children < 1 year old admitted to the paediatric ward because of airway complaints were asked to record cough sounds of their child. In all children, MLPA analysis-a variation of PCR analysis-on nasopharyngeal swab was performed (golden standard). Sixteen cough fragments representing 4 different viral pathogens were selected and presented to paediatric healthcare workers. Thirty-two paediatric nurses, 16 residents and 16 senior staff members were asked to classify the audio files and state whether the cough was due to RSV infection or not. Senior staff, nurses and residents correctly identified RSV with a sensitivity of 76.2%, 73.1% and 51.3% respectively. Correct exclusion of RSV cases was performed with a specificity of 60.8%, 60.2% and 65.3% respectively. Sensitivity ranged from 0 to 100% between colleagues; no one correctly identified all negatives. Residents had significantly lower rates of sensitivity than senior staff and nurses. This was strongly related to work experience, in which more than 3.5 years of work experience was related to the best result.Conclusion: Senior staff and nurses were better in making a cough-based diagnosis of RSV compared to residents. Both groups were able to detect the same proportion of true RSV patients based on cough sounds compared to bedside tests but could not validly distinguish RSV from other pathogens based on cough sounds. What is Known: • Many paediatric healthcare workers claim to be capable of diagnosing RSV in infants based on cough sound • Up to now, no studies investigating the recognisability of RSV based on cough sound are published What is New: • Senior staff and paediatric nurses performed better than various other bedside tests in diagnosing RSV but could not replace MLPA analysis • Residents need at least 3.5 years of work experience to be able to make a RSV diagnosis based on cough sound.

Temporal and climate characteristics of respiratory syncytial virus bronchiolitis in neonates and children in Sousse, Tunisia, during a 13-year surveillance

This study established the correlation between respiratory syncytial virus (RSV) bronchiolitis and climate factors in the area of Sousse, Tunisia, during 13 years (2003-2015), from neonates and children <= 5 years old and hospitalized in Farhat Hached University-Hospital of Sousse. The meteorological data of Sousse including temperature, rainfall, and humidity were obtained. RSV detection was carried out with the direct immunofluorescence assay. The impact of climate factors on viral circulation was statistically analyzed. From 2003 to 2015, the total rate of RSV bronchiolitis accounted for 34.5% and peaked in 2007 and 2013. RSV infection was higher in male cases and pediatric environment (p<0.001) and was detected in 47.3% of hospitalizations in intensive care units. The epidemic of this pathogen started in October and peaked in January (41.6%). When the infectivity of RSV was at its maximum, the monthly average rainfall was high (31 mm) and the monthly average temperature and the monthly average humidity were at their minimum (11 °C and 66%, respectively). RSV activity was negatively correlated with temperature (r = - 0.78, p = 0.003) and humidity (r = - 0.62, p = 0.03). Regression analysis showed that the monthly average temperature fits into a linear model (R² = 61%, p < 0.01). No correlation between RSV activity and rainfall was observed (p = 0.48). The meteorological predictions of RSV outbreaks with specific Tunisian climate parameters will help in determining the optimal timing of appropriate preventive strategies. In the area of Sousse, preventive measures should be enhanced since October especially, when the temperature is around 11 °C and humidity is above 60%.

[HYPERTONIC SALINE FOR HOSPITALIZED INFANTS WITH ACUTE BRONCHIOLITIS IN ISRAEL IN 2018]

INTRODUCTION

Inhalations of hypertonic saline is a known therapy for infants diagnosed with acute bronchiolitis. Recent meta-analysis has shown that it can reduce the length of hospitalization and decrease the chances of admission.

AIMS

To assess the extent of use of hypertonic saline inhalations in the pediatric wards in Israel in 2018.

METHODS

During October 2018 a detailed questionnaire was emailed to all the managers of pediatric wards in Israel. The questions related to treatments given to infants with acute bronchiolitis in pediatric wards and emergency departments in 2018. All results underwent statistical analysis.

RESULTS

A total of 22/28 (78%) of all pediatric wards managers completed the questionnaire; 17/22 (77%) routinely use hypertonic saline in their wards. In 15 out of the 17 wards the hypertonic saline is also provided at their emergency department. In 12 wards (70%) the saline is provided together with a bronchodilator, in 4 (24%) with inhaled steroids, and in 2 (12%) with adrenaline.

CONCLUSIONS

In most pediatric wards and their emergency departments in Israel, hypertonic saline with bronchodilators is routinely used to treat infants with acute bronchiolitis.

Vaccination Status and Resource Use During Hospital Visits for Respiratory Illnesses

OBJECTIVES

To evaluate variation in resource use for children with acute respiratory tract illness (ARTI) by vaccination status.

METHODS

We conducted a retrospective cohort study of children 0 to 16 years of age at 5 children's hospitals with 1 of 4 ARTI diagnoses (pneumonia, croup, asthma, and bronchiolitis) between July 2014 and June 2016. The predictor variable was provider-documented up-to-date (UTD) vaccination status (yes or no). Outcomes were receipt of each of the following tests or treatments (yes or no): complete blood cell count, blood cultures, C-reactive protein (CRP) level testing, viral testing, influenza testing, pertussis testing, chest radiographs, neck radiographs, antibiotics, and corticosteroids. We generated multivariable logistic regression models to examine the associations between our predictor and outcomes.

RESULTS

Of the 2302 participants included in analysis, 568 (25%) were diagnosed with pneumonia, 343 (15%) were diagnosed with croup, 653 (28%) were diagnosed with asthma, and 738 (32%) were diagnosed with bronchiolitis. Most (92%) vaccination statuses were documented as UTD. Across conditions, children whose vaccination status was documented as not UTD had higher adjusted odds of receiving a complete blood cell count, blood culture, CRP level testing, and influenza testing (P < .001). Children with pneumonia whose vaccination status was documented as not UTD had higher adjusted odds of receiving CRP level testing and influenza testing (P < .001). Children with croup whose vaccination status was documented as not UTD had higher adjusted odds of receiving blood cultures (P < .001).

CONCLUSIONS

Children with ARTI whose vaccination status was documented as not UTD had higher odds of undergoing laboratory testing compared with children whose vaccination status was documented as UTD.