Long-term pulmonary function testing in pediatric bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation

Detection of Bronchiolitis Obliterans Syndrome after Pediatric Hematopoietic Stem Cell Transplantation: An Official American Thoracic Society Clinical Practice Guideline

Background: Many children undergo allogeneic hematopoietic stem cell transplantation (HSCT) for the treatment of malignant and nonmalignant conditions. Unfortunately, pulmonary complications occur frequently post-HSCT, with bronchiolitis obliterans syndrome (BOS) being the most common noninfectious pulmonary complication. Current international guidelines contain conflicting recommendations regarding post-HSCT surveillance for BOS, and a recent NIH workshop highlighted the need for a standardized approach to post-HSCT monitoring. As such, this guideline provides an evidence-based approach to detection of post-HSCT BOS in children. Methods: A multinational, multidisciplinary panel of experts identified six questions regarding surveillance for, and evaluation of, post-HSCT BOS in children. A systematic review of the literature was undertaken to answer each question. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate the quality of evidence and the strength of recommendations. Results: The panel members considered the strength of each recommendation and evaluated the benefits and risks of applying the intervention. In formulating the recommendations, the panel considered patient and caregiver values, the cost of care, and feasibility. Recommendations addressing the role of screening pulmonary function testing and diagnostic tests in children with suspected post-HSCT BOS were made. Following a Delphi process, new diagnostic criteria for pediatric post-HSCT BOS were also proposed. Conclusions: This document provides an evidence-based approach to the detection of post-HSCT BOS in children while also highlighting considerations for the implementation of each recommendation. Further, the document describes important areas for future research.

Late-onset pulmonary complications following allogeneic hematopoietic cell transplantation in pediatric patients: a prospective multicenter study

The primary objective of our multicenter prospective study was to describe the incidence of late-onset non-infectious pulmonary complications (LONIPCs) in children undergoing hematopoietic cell transplantation (HCT) using sensitive criteria for pulmonary function test (PFT) abnormalities including the non-specific pattern of airflow obstruction. Secondary objectives were to assess the factors associated with LONIPC occurrence and the sensitivity of the 2014 NIH-Consensus Criteria of bronchiolitis obliterans syndrome (BOS). PFT and clinical assessment were performed prior to HCT and at 6, 12, 24, and 36 months post-HCT. LONIPC diagnosis was validated by an Adjudication Committee. The study comprised 292 children from 12 centers. Thirty-two individuals (11%, 95% CI: 8-15%) experienced 35 LONIPCs: 25 BOS, 4 interstitial lung diseases, 4 organizing pneumonia and 2 pulmonary veno-occlusive diseases. PFT abnormalities were obstructive defects (FEV1/FVC z-score < -1.645; n = 12), restrictive defects (TLC < 80% predicted, FEV1 and FVC z-scores < -1.645; n = 7) and non-specific pattern (FEV1 and FVC z-score< -1.645, FEV1/FVC z-score > -1.645, and TLC > 80% predicted; n = 8). HCT for malignant disease was the only factor associated with LONIPC (P = 0.04). The 2014 NIH-Consensus Criteria would only diagnose 8/25 participants (32%) as having BOS. In conclusion, 11% of children experienced a LONIPC in a prospective design. Clinical Trials.gov identifier (NCT number): NCT02032381.

Correlation analysis between serum total IgE and FeNO and idiosyncratic reaction in bronchiolitis

OBJECTIVE

This article focused on the correlation between the changes of serum total Immunoglobulin E (IgE) and Fractional exhaled Nitric Oxide (FeNO) and idiosyncratic reactions in children with bronchiolitis.

METHODS

One hundred children with bronchiolitis and fifty healthy children were enrolled. Serum total IgE and FeNO were assessed, and the diagnostic value for bronchiolitis and the correlation with the severity of bronchiolitis were analyzed. Bronchiolitis children were divided into idiosyncratic + bronchiolitis and non-idiosyncratic + bronchiolitis groups, the relationship between serum total IgE and FeNO and idiosyncratic reaction was determined, and the diagnostic value of serum total IgE and FeNO for idiosyncratic bronchiolitis was examined.

RESULTS

FeNO in bronchiolitis children was lower than that in healthy children but there was no significant difference in serum total IgE levels between the two populations. Serum total IgE increased while FeNO decreased with the aggravation of bronchiolitis in bronchiolitis children. The serum total IgE was positively correlated while FeNO was negatively correlated with the severity of bronchiolitis. Serum total IgE was higher in children with idiosyncratic bronchiolitis, but serum total IgE and FeNO were not the risk factors for idiosyncratic bronchiolitis; Area Under the Curve (AUC) of serum total IgE and FeNO for the diagnosis of idiosyncratic bronchiolitis was less than 0.7.

CONCLUSION

Serum total IgE and FeNO in children with bronchiolitis are related to disease severity and idiosyncratic reaction. FeNO has a diagnostic value for bronchiolitis, but not for idiosyncratic bronchiolitis.

ERS/EBMT clinical practice guidelines on treatment of pulmonary chronic graft-versus-host disease in adults

Chronic graft-versus-host disease (cGvHD) is a common complication after allogeneic haematopoietic stem cell transplantation, characterised by a broad disease spectrum that can affect virtually any organ. Although pulmonary cGvHD is a less common manifestation, it is of great concern due to its severity and poor prognosis. Optimal management of patients with pulmonary cGvHD is complicated and no standardised approach is available. The purpose of this joint European Respiratory Society (ERS) and European Society for Blood and Marrow Transplantation task force was to develop evidence-based recommendations regarding the treatment of pulmonary cGvHD phenotype bronchiolitis obliterans syndrome in adults. A multidisciplinary group representing specialists in haematology, respiratory medicine and methodology, as well as patient advocates, formulated eight PICO (patient, intervention, comparison, outcome) and two narrative questions. Following the ERS standardised methodology, we conducted systematic reviews to address these questions and used the Grading of Recommendations Assessment, Development and Evaluation approach to develop recommendations. The resulting guideline addresses common therapeutic options (inhalation therapy, fluticasone-azithromycin-montelukast, imatinib, ibrutinib, ruxolitinib, belumosudil, extracorporeal photopheresis and lung transplantation), as well as other aspects of general management, such as lung functional and radiological follow-up and pulmonary rehabilitation, for adults with pulmonary cGvHD phenotype bronchiolitis obliterans syndrome. These recommendations include important advancements that could be incorporated in the management of adults with pulmonary cGvHD, primarily aimed at improving and standardising treatment and improving outcomes.

Multiple breath washout and oscillometry after allogenic HSCT: a scoping review

Pulmonary chronic graft-versus-host disease (cGVHD) is a substantial cause of pulmonary morbidity and mortality post-haematopoietic stem cell transplantation (HSCT). Current spirometry-based monitoring strategies have significant limitations. Understanding the utility of novel peripheral airway function tests - multiple breath washout (MBW) and oscillometry - is critical in efforts to improve detection, facilitate earlier intervention and improve outcomes. In this scoping review, we identified 17 studies investigating MBW or oscillometry, or both, after allogenic HSCT. Despite small study numbers limiting the ability to draw firm conclusions, several themes were evident. Detectable peripheral airway abnormality in MBW occurred in a substantial proportion prior to HSCT. MBW indices post-HSCT were more frequently abnormal than spirometry when reporting group data and among those with extrapulmonary cGVHD and pulmonary cGVHD. Changes in MBW indices over time may be more indicative of pulmonary complications than absolute values at any given time point. Oscillometry indices were often normal at baseline, but more frequently abnormal in those who developed pulmonary cGVHD. Pooling currently available individual participant data across these studies may improve our ability to formally compare their respective sensitivity and specificity at specific time points and assess the trajectory of MBW and oscillometry indices over time.

Bronchiolitis obliterans syndrome after lung or haematopoietic stem cell transplantation: current management and future directions

Bronchiolitis obliterans syndrome (BOS) may develop after either lung or haematopoietic stem cell transplantation (HSCT), with similarities in histopathological features and clinical manifestations. However, there are differences in the contributory factors and clinical trajectories between the two conditions. BOS after HSCT occurs due to systemic graft-versus-host-disease (GVHD), whereas BOS after lung transplantation is limited to the lung allograft. BOS diagnosis after HSCT is more challenging, as the lung function decline may occur due to extrapulmonary GVHD, causing sclerosis or inflammation in the fascia or muscles of the respiratory girdle. Treatment is generally empirical with no established effective therapies. This review provides rare insights and commonalities of both conditions, that are not well elaborated elsewhere in contemporary literature, and highlights the importance of cross disciplinary learning from experts in other transplant modalities. Treatment algorithms for each condition are presented, based on the published literature and consensus clinical opinion. Immunosuppression should be optimised, and other conditions or contributory factors treated where possible. When initial treatment fails, the ultimate therapeutic option is lung transplantation (or re-transplantation in the case of BOS after lung transplantation) in carefully selected candidates. Novel therapies under investigation include aerosolised liposomal cyclosporine, Janus kinase inhibitors, antifibrotic therapies, and (in patients with BOS after lung transplantation) B-cell–directed therapies. Effective novel treatments that have a tangible impact on survival and thereby avoid the need for lung transplantation or re-transplantation are urgently required.

Artificial Intelligence Algorithm-Based High-Resolution Computed Tomography Image in the Treatment of Children with Bronchiolitis Obliterans by Traditional Chinese Medicine Method of Resolving Phlegm and Removing Blood Stasis

This research was aimed to explore the application of high-resolution computed tomography (HRCT) based on intelligent iterative reconstruction technique in the early diagnosis and treatment of bronchiolitis obliterans (BO) in children and to explore the efficacy of traditional Chinese medicine (TCM) in resolving phlegm and removing blood stasis. Sixty pediatric patients with BO were selected as the study subjects and diagnosed by HRCT scanning, and the scanned images were processed by iterative reconstruction technique. The patients were treated with TCM therapy of resolving phlegm and removing blood stasis alone (group A), HRCT-guided TCM therapy of resolving phlegm and removing blood stasis (group B), and iterative reconstruction HRCT-guided TCM therapy of resolving phlegm and removing blood stasis (group C). The results showed that the lung HRCT image after iterative reconstruction was closer to the original image than that after filtered back projection reconstruction, and the edge of the image after filtered back projection reconstruction was more blurred and the noise was higher. The image obtained by iterative reconstruction technique was smoother and clearer, and the image stability after iterative reconstruction was higher. The treatment results showed that the proportion of moderate and severe obstruction in group C was 5.18%, which was significantly lower than that in group A (18.75%) and group B (11.29%), and group B was significantly lower than that in group A (18.75%) (P < 0.05). The proportion of clinical effect in group C after treatment was 70.18%, significantly higher than that in group A (55.5%) and group B (63.34%), and that in group B was significantly higher than that in group A (55.5%) (P < 0.05). In summary, the lung HRCT after iterative reconstruction can more clearly and intuitively show the lesion site, which has a key role in guiding the early diagnosis and treatment planning of BO; the HRCT image based on iterative reconstruction technique combined with TCM treatment of removing blood stasis and resolving phlegm has a better therapeutic effect on children, with a high application value.

Long-Term Health Effects of Curative Therapies on Heart, Lungs, and Kidneys for Individuals with Sickle Cell Disease Compared to Those with Hematologic Malignancies

The goal of curing children and adults with sickle cell disease (SCD) is to maximize benefits and minimize intermediate and long-term adverse outcomes so that individuals can live an average life span with a high quality of life. While greater than 2000 individuals with SCD have been treated with curative therapy, systematic studies have not been performed to evaluate the long-term health effects of hematopoietic stem cell transplant (HSCT) in this population. Individuals with SCD suffer progressive heart, lung, and kidney disease prior to curative therapy. In adults, these sequalae are associated with earlier death. In comparison, individuals who undergo HSCT for cancer are heavily pretreated with chemotherapy, resulting in potential acute and chronic heart, lung, and kidney disease. The long-term health effects on the heart, lung, and kidney for children and adults undergoing HSCT for cancer have been extensively investigated. These studies provide the best available data to extrapolate the possible late health effects after curative therapy for SCD. Future research is needed to evaluate whether HSCT abates, stabilizes, or exacerbates heart, lung, kidney, and other diseases in children and adults with SCD receiving myeloablative and non-myeloablative conditioning regimens for curative therapy.

Pediatric pulmonology 2020 year in review: Rare and diffuse lung disease

Pediatric Pulmonology publishes original research, review articles, and case reports on topics related to a wide range of children's respiratory disorders. Here we review some of the most notable manuscripts published in 2020 in this journal on (1) children's interstitial lung disease (chILD), (2) congenital airway and lung anomalies, and (3) primary ciliary dyskinesia and other non-cystic fibrosis bronchiectasis. The articles reviewed are discussed in context with published works from other journals.

Prospective phase II trial of montelukast to treat bronchiolitis obliterans syndrome after hematopoietic cell transplant and investigation into BOS pathogenesis

BACKGROUND

Bronchiolitis obliterans syndrome (BOS) is a severe manifestation of chronic graft-versus-host disease (cGVHD) following hematopoietic cell transplantation (HCT). Montelukast interrupts cysteinyl leukotriene activity and may diminish the activation and homing of cells to bronchioles and subsequent fibrosis.

OBJECTIVE

We performed a prospective phase II trial to test whether montelukast altered lung decline for patients with BOS after HCT.

STUDY DESIGN

We performed a single arm, open-label, multi-institutional study with primary endpoints of: i) FEV1 stability or improvement (<15% decline) and ii) slope of FEV1<1 point decline after six months treatment. Secondary endpoints included symptom and functional response, and immune correlates investigating the role of leukotrienes in BOS progression.

RESULTS

25 patients enrolled with moderate to severe lung disease after three months of stable cGVHD therapy. Montelukast was well-tolerated and no patient required escalation of BOS-directed therapy. At the primary endpoint, all evaluable patients (n=23) met criteria for treatment success using FEV1% predicted, and all but one had stable or improved FEV1 slope. In those with >5% FEV1 improvement, clinically meaningful improvements were seen in the Lee scores of breathing, energy, and mood. Improvements in the Human Activity Profile and 6-minute-walk test were observed in those with <5% FEV1 decline. Overall survival was 87% at two-years. Immune correlates showed elevated leukotriene receptor levels on blood eosinophils and monocytes vs. healthy controls, elevated urine leukotrienes in 45% of cohort, and cysteinyl leukotriene receptors on bronchoalveolar lavage subsets and a predominance of Th2 T cells, all pre-treatment.

CONCLUSIONS

These data suggest that montelukast may safely halt progression of BOS after HCT and that leukotrienes may play a role in the biology of BOS.

Noninfectious complications of hematopoietic cell transplantation

Noninfectious lung diseases contribute to nonrelapse mortality. They constitute a spectrum of diseases that can affect the parenchyma, airways, or vascular pulmonary components and specifically exclude cardiac and renal causes. The differential diagnoses of these entities differ as a function of time after hematopoietic cell transplantation. Specific diagnosis, prognosis, and optimal treatment remain challenging, although progress has been made in recent decades.

The association of lung function changes with outcomes in children with bronchiolitis obliterans syndrome after hematopoietic stem cell transplantation

BACKGROUND

Bronchiolitis obliterans syndrome (BOS) is a life-threatening respiratory complication of allogeneic hematopoietic stem cell transplantation (HSCT). Although pulmonary function testing is crucial for monitoring BOS, little information exists on the association of these test results with outcomes in children with BOS.

OBJECTIVES

The purpose of this study was to determine the correlation between changes in lung function after BOS diagnosis and long-term outcomes.

METHODS

A total of 428 children underwent allogeneic HSCT from January 2006 to December 2017 at Asan Medical Center. Twenty-three (5.4%) were diagnosed with BOS after allogeneic HSCT, and their clinical data were reviewed. Twenty-one subjects underwent regular pulmonary function testing for 24 months after BOS diagnosis.

RESULTS

Among the 21 children with BOS, 8 died, 5 underwent lung transplantation (TPL), and 15 required oxygen (O₂ ) therapy. The FEV₁ % predicted (pred), FVC% pred, and FEF_25%-75% pred were 37.8 ± 12.7% (mean ± SD), 62.2 ± 16.2%, and 16.4 ± 9.6%, respectively, at the time of BOS diagnosis. Changes in the FEV₁ % pred were greater in the death and lung TPL groups (-24.8 ± 22.3%) than in the survival without lung TPL group (5.7 ± 21.8%) and greater in the O₂ therapy (-19.4 ± 23.4%) group than in the group without O₂ therapy (14.2 ± 20.0%) during the first 3 months after BOS diagnosis.

CONCLUSION

The change in FEV₁ during the first 3 months after BOS diagnosis correlated with outcomes including survival, lung TPL, and O₂ therapy. These results suggest that more active intervention in the first 3 months after BOS diagnosis may be needed to improve prognosis.

Follow-up on the therapeutic effects of a budesonide, azithromycin, montelukast, and acetylcysteine (BAMA) regimen in children with post-infectious bronchiolitis obliterans

Background

Post-infectious bronchiolitis obliterans (PIBO) is a rare, severe chronic lung disease without optimal treatment. Currently, treatment in children mainly relies on systemic corticosteroids, but long-term use of these drugs may lead to adverse reactions. This study aimed to evaluate the short-term efficacy of the budesonide, azithromycin, montelukast, and acetylcysteine (BAMA) regimen in paediatric PIBO patients and whether it can reduce systemic corticosteroid use.

Methods

This was a prospective study. From June 2017 to July 2020, patients diagnosed with PIBO at Yuying Children’s Hospital of Wenzhou Medical University were treated with the BAMA regimen for 3 months. Methylprednisolone was added only when the clinical manifestations did not improve or deteriorated. All patients were followed up every 2 to 4 weeks, and changes in clinical symptoms were recorded. Pulmonary function tests and high-resolution computed tomography (HRCT) were performed, and systemic corticosteroid use was recorded after the 3-month follow-up.

Results

A total of 75 patients with PIBO were included; overall, 54 patients completed the course of treatment. After treatment, the respiratory manifestations were improved in 37 patients (68.5%), but 4 patients (7.4%) showed decreased exercise tolerance, and 2 patients (3.7%) were readmitted to the hospital. Additionally, 17 (56.7%) of the 30 patients whose pulmonary function was re-examined showed improvement, and 28 (77.8%) of the 36 patients who underwent HRCT showed marked improvement. Importantly, 20 patients (54.1%) received systemic corticosteroids for 2 weeks or less, while 31.5% of patients used no corticosteroids.

Conclusions

The BAMA regimen effectively relieved clinical symptoms and signs of PIBO in children, improved pulmonary function and HRCT manifestations, and reduced the use of systemic corticosteroids.

Long-term course of bronchial inflammation and pulmonary function testing in children with postinfectious bronchiolitis obliterans

RATIONALE

Postinfectious bronchiolitis obliterans (PIBO) is a rare, chronic respiratory condition, which follows an acute insult due to a severe infection of the lower airways.

OBJECTIVES

The objective of this study was to investigate the long-term course of bronchial inflammation and pulmonary function testing in children with PIBO.

METHODS

Medical charts of 21 children with PIBO were analyzed retrospectively at the Children's University Hospital Frankfurt/Main Germany. Pulmonary function tests (PFTs) with an interval of at least 1 month were studied between 2002 and 2019. A total of 382 PFTs were analyzed retrospectively and per year, the two best PFTs, in total 217, were evaluated. Additionally, 56 sputum analysis were assessed and the sputum neutrophils were evaluated.

RESULTS

The evaluation of the 217 PFTs showed a decrease in FEV1 with a loss of 1.07% and a loss in z score of -0.075 per year. FEV1/FVC decreased by 1.44 per year. FVC remained stable, showing a nonsignificant increase by 0.006 in z score per year. However, FEV1 and FVC in L increased significantly with FEV1 0.032 L per cm and FVC 0.048 L/cm in height. Sputum neutrophils showed a significant increase of 2.12% per year.

CONCLUSION

Our results demonstrated that in patients with PIBO pulmonary function decreased significantly showing persistent obstruction over an average follow-up period of 8 years. However, persistent lung growth was revealed. In addition, pulmonary inflammation persisted clearly showing an increasing amount of neutrophils in induced sputum. Patients did not present with a general susceptibility to respiratory infections.