Outcome and treatment of late-onset noninfectious pulmonary complications after allogeneic haematopoietic SCT

Pulmonary complications post allogeneic haematopoietic stem cell transplant in children

Objectives

Haematopoietic stem cell transplant (HCT) is a cellular therapy that, whilst curative for a child's underlying disease, carries significant risk of mortality, including because of pulmonary complications. The aims of this study were to describe the burden of pulmonary complications post-HCT in a cohort of Australian children and identify risk factors for the development of these complications.

Methods

Patients were identified from the HCT databases at two paediatric transplant centres in Australia. Medical records were reviewed, and demographics, HCT characteristics and pulmonary complications documented. Relative risk ratio was used to identify risk factors for developing pulmonary complications prior to first transplant episode, and survival analysis performed to determine hazard ratio.

Results

In total, 243 children underwent transplant during the study period, and pulmonary complications occurred in 48% (117/243) of children. Infectious complications were more common (55%) than non-infective complications (18%) and 26% of patients developed both. Risk factors for the development of pulmonary complications included the following: diagnoses of MPAL (RR 2.16, P = 0.02), matched unrelated donor (RR1.34, P = 0.03), peripheral blood (RR 1.36, P = 0.028) or cord blood (RR 1.73, P = 0.012) as the stem cell source and pre-existing lung disease (RR1.72, P < 0.0001). Children with a post-HCT lung complication had a significantly increased risk of mortality compared with those who did not (HR 3.9, P < 0.0001).

Conclusion

This study demonstrates pulmonary complications continue to occur frequently in children post-HCT and contribute significantly to mortality. Highlighting the need for improved strategies to identify patients at risk pre-transplant and enhanced treatments for those who develop lung disease.

Long-term health outcomes of allogeneic hematopoietic stem cell transplantation

Background

Fifty years of hematopoietic cell transplantation (HCT) has ushered in an exciting era of cellular therapy and has led to enormous progress in improving the outcomes of patients with both malignant and non-malignant hematologic disease. As the survival of transplanted patients has increased, so has the recognition of long-term complications related to this therapy.

Purpose

The goal of this review is to highlight some of the most common long-term complications of HCT.

Data sources

To this end, we have conducted a review of the published literature on the long-term complications of HCT encompassing the past 50 years.

Study selection

We have endeavored to include long-term complications reported in research articles, case series and case reports, reviews, and abstracts. We have focused primarily on adult allogeneic HCT, but have included some data from studies of pediatric allogeneic HCT as well. We have also prioritized the literature published in the last 15 years.

Data extraction

Key data supporting the onset and prevalence of the most common long-term complications was extracted.

Limitations

While the list of long-term complications extracted and reported was comprehensive, it was not exhaustive.

Conclusions

We have endeavored to highlight some of the most common long-term complications of HCT, the recognition and management of which constitutes an important part of HCT survivorship care.

Association between early corticosteroid administration and long-term survival in non-infectious pulmonary complications after allogeneic hematopoietic stem cell transplantation

Non-infectious pulmonary complications (NIPCs) after allogeneic hematopoietic stem cell transplantation (HSCT) are associated with poor outcomes. It is important to maximize the effectiveness of primary treatment because secondary treatment has not been established. We analyzed data from 393 patients who underwent allogeneic HSCT during a 10-year period. Thirty-seven were diagnosed with NIPCs, which consisted of idiopathic pneumonia syndrome, bronchiolitis obliterans, and interstitial lung disease including cryptogenic organizing pneumonia. Among these, 18 died (Dead group) while 19 remained alive (Alive group) during the study period. The median time between NIPC diagnosis and first administration of ≥ 1 mg/kg/day corticosteroids (prednisolone dose equivalent) was significantly longer in the Dead group than the Alive group, at 9 days versus 4 days (p = 0.01). We further divided these cases into those who received prednisolone within seven days and after 8 days. We found that the ≤ 7 days group were more likely to survive after their NIPC diagnosis compared to the ≥ 8 days group (p = 0.06). Our analysis showed that early initiation of corticosteroid therapy is associated with long-term survival in NIPCs.

Sleep-related breathing disorder in non-infectious pulmonary complications after pediatric allogeneic stem cell transplantation

BACKGROUND

Chronic lung problems are a rare but serious complication of allogeneic hematopoietic stem cell transplantation (HSCT). We studied clinical phenotypes and polysomnography appearance of breathing abnormality in late onset non-infectious pulmonary complications (NIPS).

METHODS

We reviewed Finnish national reference database between the years 1999 and 2016. We identified 12 children with most severely decreased pulmonary function and performed polysomnography and 24 aged-matched controls out of 325 performed pediatric allogeneic HSCTs.

RESULTS

All patients with NIPS had severely decreased pulmonary function already at 6 months post HSCT with median FEV₁ value 42% (interquartile range (IQR) 30-52%) of predicted normal values. Seven children had obstructive and five children more restrictive lung function. Children with obstructive lung function showed laborious breathing (7/7), decreased oxygenation and ventilation-to-perfusion mismatch (6/7), or REM-sleep-related hypoventilation (4/7) on polysomnography. Children with restrictive lung function (5/12) did not show sleep-related breathing disorder.

CONCLUSIONS

Children going through allogeneic HSCT who develop severe chronic obstructive lung function are more likely to present with sleep-related hypoxia and hypoventilation than children with restrictive lung function.

IMPACT

Children with severe obstructive lung function and chronic lung graft-versus-host disease following hematopoietic stem cell transplantation are more likely to present with sleep-related mild hypoxia and hypoventilation than children with restrictive lung disease. To our knowledge there are no reports on sleep-related breathing disorders and ventilatory function measured by polysomnography in children with pulmonary complications after allogeneic HSCT. Polysomnography may add to the differential diagnostics between patients with BOS and other non-infectious pulmonary complications.

The economic burden of NIPC and BOS following allogeneic HSCT in patients with commercial insurance in the United States

Noninfectious pulmonary complications (NIPC) after allogeneic hematopoietic stem cell transplantation (alloHSCT), including bronchiolitis obliterans syndrome (BOS), cause significant morbidity and mortality, but their impact on health care resource utilization (HRU) and costs is unknown. This longitudinal retrospective study quantified the economic burden of NIPC and BOS in alloHSCT patients using commercial claims data from the IQVIA PharMetrics Plus database. Study patients were aged 0 to 64 years and underwent alloHSCT between 1 January 2006 and 30 September 2018, and were observable 12 months before and up to 5 years after index alloHSCT. NIPC patients were identified using International Classification of Disease (ICD) diagnosis codes. Outcomes were mean per patient HRU (inpatient admissions, outpatient office, hospital visits, and prescription medications) and costs paid by insurers in each post-transplant year. Among 2162 alloHSCT patients, 254 developed NIPCs, and 155 were propensity score (PS)-matched to non-NIPC patients. The year following transplantation, NIPC patients had significantly higher inpatient admission rates (3.8 ± 3.2 vs non-NIPC: 2.6 ± 2.4; P < .001) and higher total costs ($567 870 vs $412 400; P = .07), reflecting higher costs for inpatient admissions ($452 475 vs $300 202; P = .06). Among those observable for more years, costs remained higher for NIPC patients, reflecting significantly higher inpatient admission rates in the first 3 years following transplant. Subanalysis of patients with diagnoses likely reflective of BOS were consistent with these findings. AlloHSCT patients who developed NIPC had higher health care resource utilization and incurred higher costs compared with alloHSCT patients who did not develop NIPC following transplant.

Pulmonary Complications in Hematopoietic Stem Cell Transplant Recipients-A Clinician Primer

Hematopoietic stem cell transplants (HSCT) are becoming more widespread as a result of optimization of conditioning regimens and prevention of short-term complications with prophylactic antibiotics and antifungals. However, pulmonary complications post-HSCT remain a leading cause of morbidity and mortality and are a challenge to clinicians in both diagnosis and treatment. This comprehensive review provides a primer for non-pulmonary healthcare providers, synthesizing the current evidence behind common infectious and non-infectious post-transplant pulmonary complications based on time (peri-engraftment, early post-transplantation, and late post-transplantation). Utilizing the combination of timing of presentation, clinical symptoms, histopathology, and radiographic findings should increase rates of early diagnosis, treatment, and prognostication of these severe illness states.

Lung transplantation for late-onset non-infectious chronic pulmonary complications of allogenic hematopoietic stem cell transplant

Background

Late onset non-infectious pulmonary complications (LONIPCs) following allogenic hematopoietic stem cell transplantation (allo-HSCT) confer a significant mortality risk. Lung transplantation (LTx) has the potential to provide survival benefit but the impact of prior allo-HSCT on post-LTx outcomes is not well studied.

Methods

This retrospective, single-centre cohort study assessed the post-LTx outcomes of adults with LONIPCs of allo-HSCT. Outcomes of LTx for LONIPCs were compared to propensity-score matched LTx controls (n = 38, non-HSCT) and recipients of re-LTx (n = 70) for chronic lung allograft dysfunction (CLAD).

Results

Nineteen patients underwent DLTx for LONIPCs of allo-HSCT between 2003 and 2019. Post-LTx survival was 50% at 5-years. Survival to 1-year post-LTx was similar to matched controls (p = 0.473). Survival, conditional on 1-year survival, was lower in the allo-HSCT cohort (p = 0.034). An increased risk of death due to infection was identified in the allo-HSCT cohort compared to matched controls (p = 0.003). Compared to re-LTx recipients, the allo-HSCT cohort had superior survival to 1-year post-LTx (p = 0.034) but conditional 1-year survival was similar (p = 0.145).

Conclusion

This study identifies an increased risk of post-LTx mortality in recipients with previous allo-HSCT, associated with infection. It supports the hypothesis that allo-HSCT LTx recipients are relatively more immunosuppressed than patients undergoing LTx for other indications. Optimisation of post-LTx immunosuppressive and antimicrobial strategies to account for this finding should be considered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01699-8.

Late Noninfectious Pulmonary Complications in Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) is an established therapeutic modality for a number of malignant and nonmalignant conditions. Pulmonary complications following HSCT are associated with increased mortality and morbidity. These complications may be classified into infectious versus noninfectious, and early versus late based on the time of occurrence post-transplant. Thus, exclusion of infectious etiologies is the first step in the diagnoses of pulmonary complications. Late onset noninfectious pulmonary complications typically occur 3 months post-transplant. Bronchiolitis obliterans is the major contributor to late-onset pulmonary complications, and its clinical presentation, pathogenesis, and current therapeutic approaches are discussed. Idiopathic pneumonia syndrome is another important complication which usually occurs early, although its onset may be delayed. Organizing pneumonia is important to recognize due to its responsiveness to corticosteroids. Other late onset noninfectious pulmonary complications discussed here include pulmonary venoocclusive disease, pulmonary cytolytic thrombi, pleuroparenchymal fibroelastosis, thoracic air leak syndrome, and posttransplant lymphoproliferative disorders.

Diagnosis and treatment of bronchiolitis obliterans syndrome accessible universally

The incidence of bronchiolitis obliterans syndrome (BOS), a devastating manifestation of chronic graft-versus-host-disease, may rise globally due to steady increases in utilization of allogeneic hematopoietic cell transplantation (HCT). Though some advances have occurred in the past decade regarding understanding of the pathogenesis, diagnosis and treatment of BOS, the overall mortality and morbidity remain very high. We sought to determine the current diagnostic and therapeutic challenges, which can potentially hinder optimal management of BOS both in developed and developing countries. We performed a comprehensive systematic review of both modern diagnostic modalities and treatments and then assessed which of them would be universally accessible. The 2014 National Institutes of Health chronic GVHD criteria remains the gold standard tool for diagnosing BOS. Important elements of treatment involve early and accurate detection, as well as utilizing the treatment modalities with known (but variable efficacy) e.g. fluticasone-azithromycin-montelukast [FAM] combination, etanercept, extra-corporeal photopheresis [ECP], lung transplantation, and prompt treatment of complications including infections in sufferers of BOS. Our results indicate that optimum diagnostic tools are not readily available in some parts of the world for early detection, which include a lack of CT scanners, unavailability of pulmonary function testing tools, absence of sub-specialists, lack of certain effective treatments and late referral for lung transplant. We present a systematic review of current literature along with recommendations for available therapies to guide practitioners to optimize the long-term outcomes in HCT survivors regardless of access to experts and expensive therapies.

Noninfectious lung complications after allogeneic haematopoietic stem cell transplantation

Epidemiological data on late-onset noninfectious pulmonary complications (LONIPCs) following allogeneic haematopoietic stem cell transplantation (HSCT) are derived exclusively from retrospective studies and are conflicting. We aimed to evaluate prospectively the incidence, risk factors and outcomes for LONIPCs.All consecutive patients scheduled to receive allogeneic HSCT between 2006 and 2008 at a university teaching hospital in France were screened for inclusion in the study. Eligible patients were those surviving at day 100. Among 243 screened patients, 198 patients were included in the analysis. The median (interquartile range) follow-up was 72.3 (15.2-88.5) months. 55 LONIPCs were diagnosed in 43 patients. Bronchiolitis obliterans syndrome (n=22) and interstitial lung disease (n=12) were the most common LONIPCs. At 36 months after inclusion, the estimated cumulative incidence of LONIPCs was 19.8% (95% CI 14.2-25.3%). The estimated median survival after the diagnosis of LONIPCs was 78.5 months (95% CI 20.0-not reached). Based on a multivariate Cox model, a history of chest irradiation anytime prior to HSCT, a history of pneumonia within 100 days post-HSCT and a low mean forced expiratory flow at 25-75% of forced vital capacity at day 100 were associated with the development of LONIPCs.Our data provide clues to identify patients at high risk of developing LONIPCs. These patients should be targeted for close monitoring to provide earlier LONIPC treatment or prophylactic treatment.

Exploring the possibilities: airspace disease in the postallogeneic haematopoietic stem cell transplant period

A 50-year-old man with a history of myelodysplastic syndrome status postallogeneic haematopoietic stem cell transplantation (HSCT) in July 2013 presented in January 2014 with a 6-week history of worsening shortness of breath and dry cough. Chest imaging revealed scattered groundglass opacities in the upper lobes bilaterally and two areas of focal consolidation on the left side. Bronchoscopy with bronchoalveolar lavage grew methicillin-resistant Staphylococcus aureus and the patient was treated with a prolonged course of vancomycin without improvement in symptoms or oxygenation. Image-guided core biopsy of an area of consolidation revealed histological findings of acute fibrinous and organising pneumonia. The patient was diagnosed with what appeared to be a manifestation of chronic graft-versus-host disease of the lung and started on high-dose corticosteroids with resultant improvement in symptoms. The response was short-lived and the patient expired 2 months later.

An update on pulmonary complications of hematopoietic stem cell transplantation

The indications for hematopoietic stem cell transplantation (HSCT) continue to expand. However, the risk for pulmonary complications post-HSCT continues to be high. Early recognition and treatment of pulmonary complications may improve outcomes. This is an overview of diagnosis, manifestations, and treatment of the most common infectious and noninfectious pulmonary complications post-HSCT. Knowing the patient's timeframe post-HSCT (preengraftment, postengraftment, late), type of HSCT (allogeneic vs autologous), radiographic findings, and clinical presentation can help to differentiate between the many pulmonary complications. This article will also address pretransplantation evaluation and infectious and noninfectious complications in the patient post-HSCT. While mortality post-HSCT continues to improve, respiratory failure continues to be the leading cause of ICU admissions for patients who have undergone HSCT. Mechanical ventilation is a predictor of poor outcomes in these patients, and further research is needed regarding their critical care management, treatment options for noninfectious pulmonary complications, and mortality prediction models posttransplantation.

Pulmonary hypertension after hematopoietic stem cell transplantation

Pulmonary hypertension (PH) is a potentially fatal complication of hematopoietic stem cell transplantation (HSCT). Given its nonspecific clinical presentation, it is likely that this clinical entity is underdiagnosed after HSCT. Data describing the incidence, risk factors, and etiology of PH in HSCT recipients are minimal. Physicians caring for HSCT recipients should be aware of this severe post-transplant complication because timely diagnosis and treatment may allow improved clinical outcomes. We summarize the pathophysiology, clinical presentation, diagnosis, and management of PH in HSCT recipients.

Protective role of T-bet and Th1 cytokines in pulmonary graft-versus-host disease and peribronchiolar fibrosis

T-box expressed in T cells (T-bet) is a critical transcription factor for T helper (Th) 1 responses. Although Th1 cells are thought to contribute to certain alloimmune responses, their role in pulmonary graft-versus-host disease (GVHD) is uncertain. We have established a murine model of acute pulmonary GVHD after hematopoietic cell transplant (HCT) and inhaled LPS exposure. We tested the hypothesis that pulmonary GVHD can occur independent of Th1 cells using T-bet-deficient donors. B10.BR(H2(k)) mice underwent allogeneic (Allo) or syngeneic (Syn) HCT with cells from either C57Bl/6J(H2(b)) mice (Allo wild-type [WT] or SynWT) or C57Bl/6J mice lacking T-bet (AlloTbet(-/-) or SynTbet(-/-)). After HCT, mice were exposed daily to aerosolized LPS and subsequently bronchoalveolar lavage and lung tissue were analyzed for cytokines, lymphocytic inflammation, pathology, and fibrosis. Independent of LPS exposure, AlloTbet(-/-) mice developed pulmonary GVHD manifested by lymphocytic inflammation. Furthermore, AlloTbet(-/-) mice developed features of chronic pulmonary GVHD, including increased peribronchiolar fibrosis and collagen content. LPS exposure increased neutrophil recruitment and decreased static compliance in AlloTbet(-/-) mice as compared with LPS-exposed AlloWT mice or LPS-exposed SynTbet(-/-) mice. In addition, LPS-exposed AlloTbet(-/-) mice had increased pulmonary IL-17, IL-13, and Th17 cells, and diminished regulatory T cells compared with the other groups. Our results demonstrate that Th1 cytokines are dispensable in pulmonary GVHD. In the absence of T-bet, there is increased production of Th17 and Th2 cytokines that is associated with peribronchiolar fibrosis and is further enhanced by LPS. These results suggest that the interplay between local innate immunity and non-Th1 T cell subsets contribute to chronic pulmonary GVHD.

[Bronchiolitis obliterans postallogeneic stem cell transplantation: what is new?]

Bronchiolitis obliterans (BO) is a severe complication of hematopoietic stem cell transplantation (HSCT). It is considered as a respiratory manifestation of chronic graft-versus-host disease. It is quite similar to the bronchiolitis obliterans after lung transplantation. Classical therapy associates steroids and immunosuppressive drugs, however theses procedure showed a modest efficacy and have an important morbidity. Recent progresses in the physiopathology of BO post-HSCT allow to use new treatments: mTOR inhibitors, immunotherapy, extra-corporeal photochemotherapy, and bronchial anti-inflammatory effects of azithromycin, statins or antileucotriens. This review will focus on the use of these new therapies in BO post-HSCT.