Randomized, double-blind, placebo-controlled trial of soluble tumor necrosis factor receptor: enbrel (etanercept) for the treatment of idiopathic pneumonia syndrome after allogeneic stem cell transplantation: blood and marrow transplant clinical trials network protocol

Efficacy of Ruxolitinib with corticosteroids in idiopathic pneumonia syndrome post-allogeneic hematopoietic stem cell transplantation: A single-center experience and systematic review

BACKGROUND

Idiopathic Pneumonia Syndrome (IPS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a life-threatening complication with high morbidity and mortality. IPS is thought to arise from damage caused by various inflammatory mediators. This study assesses the effectiveness of Ruxolitinib, a Janus Kinase (JAK) 1 and 2 inhibitor that blocks cytokine production, in combination with corticosteroids (CS) for managing IPS after allo-HSCT, compared to the conventional use of CS alone in a case series and a systematic review of previously published literature.

METHODS

The study includes a retrospective case series of three patients treated for IPS with Ruxolitinib and CS from the University of Kansas Medical Center and a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement 2020 guidelines. The systematic review encompassed seven studies involving 346 cases including three cases from the case series. Statistical analyses were conducted using SPSS v.25.

RESULTS

The case series included three patients with IPS after allo-HSCT who received ruxolitinib and CS with favorable results. All patients showed substantial improvement with no IPS-associated mortality. Two of the three patients in the case series were discharged on a 2 L nasal cannula, which was later discontinued during follow-up visits, while the third was discharged on room air. There was marked improvement observed on the computed tomography (CT) following the use of ruxolitinib. Of the total 346 cases included in the systematic review, the median age was 46.6 years (Range 5-72), and 62 % were males. The primary disorders were acute leukemia (52 %), chronic myeloid leukemia (12 %), myelodysplastic syndrome (11 %), Lymphoma (10 %), and others (21 %). Stem cell sources were peripheral blood (45 %), bone marrow (49 %), and cord blood (6 %). Donor types involved match unrelated (55 %), match related (36 %), and mismatched related (4.5 %). Most patients received myeloablative conditioning (81 %). Acute GVHD was observed in 47 %, and chronic GVHD in 38 %. The primary treatment was CS (96 %), with limited use of ruxolitinib (1 %) and etanercept (9.5 %). The mortality rate was 63.3 %, whereas in our case series with the use of ruxolitinib, it was zero.

CONCLUSION

The combination of Ruxolitinib and CS for treating IPS post-allo-HSCT suggested promising results in the case series, with favorable response and improved survival by blocking the cytokine production contributing to IPS. The significant mortality difference in the systematic review supports the need for innovative treatment approaches, highlighting the potential role of Ruxolitinib in CS-refractory cases. Despite the positive outcomes in the case series, the absence of randomized controlled trials emphasizes the necessity for further research.

Diffuse Alveolar Hemorrhage in Hematopoietic Cell Transplantation

Diffuse alveolar hemorrhage (DAH) is a morbid syndrome that occurs after autologous and allogeneic hematopoietic cell transplantation in children and adults. DAH manifests most often in the first few weeks following transplantation. It presents with pneumonia-like symptoms and acute respiratory failure, often requiring high levels of oxygen supplementation or mechanical ventilatory support. Hemoptysis is variably present. Chest radiographs typically feature widespread alveolar filling, sometimes with peripheral sparing and pleural effusions. The diagnosis is suspected when serial bronchoalveolar lavages return increasingly bloody fluid. DAH is differentiated from infectious causes of alveolar hemorrhage when extensive microbiological testing reveals no pulmonary pathogens. The cause is poorly understood, though preclinical and clinical studies implicate pretransplant conditioning regimens, particularly those using high doses of total-body-irradiation, acute graft-versus-host disease (GVHD), medications used to prevent GVHD, and other factors. Treatment consists of supportive care, systemic corticosteroids, platelet transfusions, and sometimes includes antifibrinolytic drugs and topical procoagulant factors. Therapeutic blockade of tumor necrosis factor-α showed promise in observational studies, but its benefit for DAH remains uncertain after small clinical trials. Even with these treatments, mortality from progression and relapse is high. Future investigational therapies could target the vascular endothelial cell biology theorized to contribute to alveolar bleeding and pathways that contribute to susceptibility, inflammation, cellular resilience, and tissue repair. This review will help clinicians navigate through the limited evidence to diagnose and treat DAH, counsel patients and families, and plan for future research.

Respiratory Failure Due to Idiopathic Pneumonia Syndrome in a Pediatric Patient After Recipient-derived Allogeneic Chimeric Antigen Receptor T-Cell Therapy

Idiopathic pneumonia syndrome (IPS) is a life-threatening complication of hematopoietic cell transplantation, but it is not clearly described following chimeric antigen receptor (CAR) T-cell therapy. We describe a child who developed IPS after receiving tisagenlecleucel for post-hematopoietic cell transplantation relapsed acute lymphoblastic leukemia and had a remarkable improvement after treatment with corticosteroids and etanercept. We discuss the implications of cytokine signaling in IPS and immunologic considerations of allogeneic CAR T cells. We anticipate that the incidence of IPS and other allogeneic phenomena will be observed more often as allogeneic CAR T cells are employed in more varied settings with more mismatched donors.

Pulmonary Specific Ancillary Treatment for Pediatric Acute Respiratory Distress Syndrome: From the Second Pediatric Acute Lung Injury Consensus Conference

OBJECTIVES

We conducted an updated review of the literature on pulmonary-specific ancillary therapies for pediatric acute respiratory distress syndrome (PARDS) to provide an update to the Pediatric Acute Lung Injury Consensus Conference recommendations and statements about clinical practice and research.

DATA SOURCES

MEDLINE (Ovid), Embase (Elsevier), and CINAHL Complete (EBSCOhost).

STUDY SELECTION

Searches were limited to children, PARDS or hypoxic respiratory failure and overlap with pulmonary-specific ancillary therapies.

DATA EXTRACTION

Title/abstract review, full-text review, and data extraction using a standardized data collection form.

DATA SYNTHESIS

The Grading of Recommendations Assessment, Development, and Evaluation approach was used to identify and summarize evidence and develop recommendations. Twenty-six studies were identified for full-text extraction. Four clinical recommendations were generated, related to use of inhaled nitric oxide, surfactant, prone positioning, and corticosteroids. Two good practice statements were generated on the use of routine endotracheal suctioning and installation of isotonic saline prior to endotracheal suctioning. Three research statements were generated related to: the use of open versus closed suctioning, specific methods of airway clearance, and various other ancillary therapies.

CONCLUSIONS

The evidence to support or refute any of the specific ancillary therapies in children with PARDS remains low. Further investigation, including a focus on specific subpopulations, is needed to better understand the role, if any, of these various ancillary therapies in PARDS.

Noninfectious Pulmonary Complications after Hematopoietic Stem Cell Transplantation

Pulmonary complications after hematopoietic stem cell transplantation (HSCT) are important sources of morbidity and mortality. Improvements in infection-related complications have made noninfectious pulmonary complications an increasingly significant driver of transplantation-related mortality. Broadly, these complications can be characterized as either early or late complications, with idiopathic pneumonia syndrome and bronchiolitis obliterans syndrome the most prevalent early and late complications, respectively. Outcomes with historical treatment consisting mainly of corticosteroids are often poor, highlighting the need for a deeper understanding of these complications' underlying disease biology to guide the adoption of novel therapies that are being increasingly used in the modern era.

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.

Incidence and predictors of idiopathic pneumonia syndrome in hematopoietic stem cell transplant patients: a nationwide registry study

Idiopathic pneumonia syndrome (IPS) is a rare but deadly complication of hematopoietic stem cell transplantation (HSCT). This study characterized the incidence and risk factors for IPS after HSCT in Taiwan. Data from January 2009 to February 2019 was collected from the Taiwan Society of BMT national registry. Forty-three (1.1%) of 3924 HSCT patients who developed IPS were identified. Incidence of IPS was lower in patients who received autologous HSCT than patients who received allogeneic HSCT (0.68% vs 1.44%, P = 0.022). Multivariate analysis showed that use of TBI and intravenous busulfan in the conditioning regimen were each independent predictor of IPS after HSCT. In addition, development of IPS was significantly associated with increased risk of death in the first 120 days post-HSCT (HR, 2.09; 95% CI, 1.08 to 4.05, P = 0.029) and 2 years post-HSCT (HR, 1.65; 95% CI, 1.07 to 2.542, P = 0.023), but not beyond 2 years post-HSCT. However, survival outcomes did not differ significantly between patients with IPS who received autologous versus allogeneic HSCT (P = 0.52). In conclusion, despite the relatively low incidence of post-HSCT IPS in Taiwan, mortality remains high. The results of this study will help to identify high-risk patients for early intervention and guide future therapeutic research.

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.

Role of the lectin pathway of complement in hematopoietic stem cell transplantation-associated endothelial injury and thrombotic microangiopathy

Hematopoietic stem cell transplantation-associated thrombotic microangiopathy (HSCT-TMA) is a life-threatening syndrome that occurs in adult and pediatric patients after hematopoietic stem cell transplantation. Nonspecific symptoms, heterogeneity within study populations, and variability among current diagnostic criteria contribute to misdiagnosis and underdiagnosis of this syndrome. Hematopoietic stem cell transplantation and associated risk factors precipitate endothelial injury, leading to HSCT-TMA and other endothelial injury syndromes such as hepatic veno-occlusive disease/sinusoidal obstruction syndrome, idiopathic pneumonia syndrome, diffuse alveolar hemorrhage, capillary leak syndrome, and graft-versus-host disease. Endothelial injury can trigger activation of the complement system, promoting inflammation and the development of endothelial injury syndromes, ultimately leading to organ damage and failure. In particular, the lectin pathway of complement is activated by damage-associated molecular patterns (DAMPs) on the surface of injured endothelial cells. Pattern-recognition molecules such as mannose-binding lectin (MBL), collectins, and ficolins—collectively termed lectins—bind to DAMPs on injured host cells, forming activation complexes with MBL-associated serine proteases 1, 2, and 3 (MASP-1, MASP-2, and MASP-3). Activation of the lectin pathway may also trigger the coagulation cascade via MASP-2 cleavage of prothrombin to thrombin. Together, activation of complement and the coagulation cascade lead to a procoagulant state that may result in development of HSCT-TMA. Several complement inhibitors targeting various complement pathways are in clinical trials for the treatment of HSCT-TMA. In this article, we review the role of the complement system in HSCT-TMA pathogenesis, with a focus on the lectin pathway.

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.

Successful ruxolitinib administration for a patient with steroid-refractory idiopathic pneumonia syndrome following hematopoietic stem cell transplantation: A case report and literature review

Idiopathic pneumonia syndrome (IPS) is an acute lung complication observed after the early posthematopoietic stem cell transplantation (HSCT) period. Ruxolitinib was effective for a patient with myelodysplastic syndrome who developed severe IPS after second HSCT. No severe adverse effects were observed. Ruxolitinib may be an alternative choice for HSCT-related IPS.

Pulmonary Complications After Pediatric Stem Cell Transplant

The number of disorders that benefit from hematopoietic stem cell transplantation (HSCT) has increased, causing the overall number of HSCT to increase accordingly. Disorders treated by HSCT include malignancy, benign hematologic disorders, bone marrow failure syndromes, and certain genetic diagnoses. Thus, understanding the complications, diagnostic workup of complications, and subsequent treatments has become increasingly important. One such category of complications includes the pulmonary system. While the overall incidence of pulmonary complications has decreased, the morbidity and mortality of these complications remain high. Therefore, having a clear differential diagnosis and diagnostic workup is imperative. Pulmonary complications can be subdivided by time of onset and whether the complication is infectious or non-infectious. While most infectious complications have clear diagnostic criteria and treatment courses, the non-infectious complications are more varied and not always well understood. This review article discusses pulmonary complications of HSCT recipients and outlines current knowledge, gaps in knowledge, and current treatment of each complication. This article includes some adult studies, as there is a significant paucity of pediatric data.

Pulmonary Complications of Pediatric Hematopoietic Cell Transplantation. A National Institutes of Health Workshop Summary

Approximately 2,500 pediatric hematopoietic cell transplants (HCTs), most of which are allogeneic, are performed annually in the United States for life-threatening malignant and nonmalignant conditions. Although HCT is undertaken with curative intent, post-HCT complications limit successful outcomes, with pulmonary dysfunction representing the leading cause of nonrelapse mortality. To better understand, predict, prevent, and/or treat pulmonary complications after HCT, a multidisciplinary group of 33 experts met in a 2-day National Institutes of Health Workshop to identify knowledge gaps and research strategies most likely to improve outcomes. This summary of Workshop deliberations outlines the consensus focus areas for future research.

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.

Critical Care of Hematopoietic Stem Cell Transplant Patients

Life-threatening complications are frequent after hematopoietic stem cell transplant (HSCT), and optimum critical care is essential to ensuring good outcomes. The immunologic consequences of HSCT result in a markedly different host response to critical illness. Infection is the most common cause of critical illness but noninfectious complications are frequent. Respiratory failure or sepsis are the typical presentations but the sequelae of HSCT can affect nearly any organ system. Pattern recognition can facilitate anticipation and early intervention in post-HSCT critical illness. HSCT critical care is a multidisciplinary endeavor. Continued investigation and focus on process improvement will continue to improve outcomes.

Acute Graft-versus-Host-Disease Other Than Typical Targets: Between Myths and Facts

Donor alloreactivity after allogeneic hematopoietic stem cell transplantation results in graft-versus-host reaction (GVHR) that may affect different organs. While skin, liver, and gastrointestinal tract are well-recognized targets of such alloreactivity early after transplant, commonly identified as acute graft-versus-host-disease (aGVHD), there is accumulating evidence from the literature that early GVHR may be directed also against other tissues. In particular, organs such as kidney, bone marrow, central nervous system, and lungs may be involved in patients experiencing aGVHD, but whether these sites represent targets or collateral damages of donor alloreactivity is matter of debate. This review summarizes the current knowledge, the potential applications, and the clinical relevance of GFHR in nontypical target organs during aGVHD. The objective of this article is to lay the basis for future efforts aiming at including these organs in grading and management of aGVHD.

Allogeneic reactivity-mediated endothelial cell complications after HSCT: a plea for consensual definitions

Endothelial cell (EC) activation has been suspected of triggering a group of rare and dismal complications that can occur after allogeneic hematopoietic stem cell transplantation (HSCT). Capillary leak syndrome, engraftment syndrome, transplant-associated microangiopathy, diffuse alveolar hemorrhage, and idiopathic pneumonia syndrome are the main nosological entities. Post-HSCT endotheliitis can be triggered by chemotherapy, infections, and calcineurin inhibitors, but allogeneic reactivity is claimed to be the common denominator. Endothelial damages are thought to activate several deleterious pathways (proapoptotic, procoagulant, proinflammatory) and can lead to multiorgan failure; however, clinical manifestations of each syndrome overlap, and their relationship with graft-versus-host disease could be minimal. The lack of well-defined diagnostic criteria does not allow for a clear-cut comparison in the current literature. Therapeutic efforts have been made to intercept the pathogenic mechanisms leading to EC dysfunction, but remission rates and survival remain mostly unsatisfactory. In this article, we have reviewed the incidence, clinical features, and treatment approaches of EC activation syndromes, and we plead for the development of internationally accepted standard definitions.

Endothelial cell function and endothelial-related disorders following haematopoietic cell transplantation

Use of haematopoietic cell transplantation (HCT) in the treatment of haematologic and neoplastic diseases may lead to life-threatening complications that cause substantial morbidity and mortality if untreated. In addition to patient- and disease-related factors, toxicity associated with HCT puts patients at risk for complications that share a similar pathophysiology involving endothelial cells (ECs). Normally, the endothelium plays a role in maintaining homeostasis, including regulation of coagulation, vascular tone, permeability and inflammatory processes. When activated, ECs acquire cellular features that may lead to phenotypic changes that induce procoagulant, pro-inflammatory and pro-apoptotic mediators leading to EC dysfunction and damage. Elevated levels of coagulation factors, cytokines and adhesion molecules are indicative of endothelial dysfunction, and endothelial damage may lead to clinical signs and symptoms of pathological post-HCT conditions, including veno-occlusive disease/sinusoidal obstruction syndrome, graft-versus-host disease, transplant-associated thrombotic microangiopathy and idiopathic pneumonia syndrome/diffuse alveolar haemorrhage. The endothelium represents a rational target for preventing and treating HCT complications arising from EC dysfunction and damage. Additionally, markers of endothelial damage may be useful in improving diagnosis of HCT-related complications and monitoring treatment effect. Continued research to effectively manage EC activation, injury and dysfunction may be important in improving patient outcomes after HCT.

Lung Transplant for Patient With Idiopathic Pneumonia Syndrome

Idiopathic pneumonia syndrome (IPS) is a serious complication after hematopoietic stem cell transplantation. Despite the high mortality rate with medical management, there have been no reported cases of lung transplants for patients with IPS. We report a case involving a 44-year-old woman who developed IPS 5 months after hematopoietic stem cell transplantation for myelodysplastic syndrome. Despite aggressive medical management, the patient required intubation and was administered extracorporeal membrane oxygenation while awaiting recovery. However, her condition continued to deteriorate, and she subsequently underwent a double lung transplant with uneventful recovery. With the high mortality of medically managed IPS, lung transplant could prove to be lifesaving.

ICU Complications of Hematopoietic Stem Cell Transplant, Including Graft vs Host Disease

Hematopoietic stem cell transplant (HSCT) is an essential treatment modality for many malignant and non-malignant hematologic diseases. Advances in HSCT techniques have dramatically decreased peri-transplant morbidity and mortality, but it remains a high-risk procedure, and a significant number of patients will require critical care during the transplant process. Complications of HSCT are both infectious and non-infectious, and the intensivist must be familiar with common infections, the management of neutropenic sepsis and septic shock, the management of respiratory failure in the immunocompromised host, and a plethora of HSCT-specific complications. Survival from critical illness after HSCT is improving, but the mortality rate remains unacceptably high. Continued research and optimization of critical care provision in this population should continue to improve outcomes.

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.

Hemophagocytic Lymphohistiocytosis and Other Culture Negative Sepsis-Like Syndromes in the ICU

There are many sepsis-like inflammatory syndromes that may be encountered by critical care practitioners. Clinically, these syndromes may imitate sepsis and are often identified after an extensive, but unrevealing evaluation for infection. In some instances, these syndromes are anticipated complications of advanced therapies for malignancy. It is vitally important to identify these disorders and treat them with specific chemotherapeutic or immunomodulating therapies. This chapter will focus on hemophagocytic lympho-histiocytosis (HLH), a rare disorder of pathologic immune system activation that presents as a sepsis-like illness in the critically ill. While treatment of HLH with chemotherapy and immunosuppression should be guided by an expert hematologist, the diagnosis is often made by the critical care medicine practitioner. We present a case illustrating the challenges of defining this syndrome in a patient with recurrent critical illness, and review the evidence underlying diagnostic and prognostic criteria for this protean syndrome. We also review several of the more common sepsis-like inflammatory syndromes that are encountered in the critical care unit along with their specific treatments.

Outcomes of Inpatient Administration of Restricted Antineoplastic Medications at a Large Academic Medical Institution

BACKGROUND

Restricting oncology and hematology medications to outpatient infusion centers may be considered when infrequent administration is required, a low risk of serious adverse effects exists, or when prompt amelioration of a condition is not expected. At the University of California, San Diego (UCSD), we created a new formulary status for medications designated "formulary, outpatient-restricted use only." This designation could optimize payer reimbursement, as well as improve patient comfort, by negating the need for inpatient admission. When the inpatient administration of a restricted medication is requested at UCSD, there ensues a loosely defined review process involving an informal conversation between the requesting prescriber and the oncology pharmacy and therapeutics (P&T) chair. Patient outcomes associated with this formulary status and informal request process are limited. The purpose of this study is to describe the use of formulary, outpatient-restricted oncology and hematology medications in the inpatient setting at a single-center, academic, and comprehensive cancer center.

METHODS

A retrospective chart review was conducted between January 1, 2015 and May 1, 2017. The primary outcome was to determine the percentage of formulary, outpatient-restricted oncology or hematology medications that were administered in the inpatient setting and continued to the outpatient setting. Secondary outcomes included overall survival, hospice enrollment, disease progression status, level of evidence supporting the medication usage, and cost.

RESULTS

Twenty-three patients and 24 outpatient-restricted medications met the inclusion criteria. Thirteen (54%) medications were continued upon discharge and eight (33%) were not continued in the outpatient setting. Five of those eight medications were discontinued as a result of patient death.

CONCLUSION

In this single-center study, approximately one-third of the outpatient-restricted medications were not continued upon discharge. The findings suggest that our informal approval process could result in the suboptimal use of formulary outpatient-restricted medications for oncology and hematology indications. A more formalized request process might lead to the more effective utilization of these medications.

Managing pulmonary complications in allogeneic hematopoietic stem cell transplantation

Introduction: Progress in allogeneic hematopoietic stem cell transplantation (HSCT) procedures has been associated with improved survival in HSCT recipients. However, they have also brought to light organ-specific complications, especially pulmonary complications. In this setting, pulmonary complications are consistently associated with poor outcomes, and improved management of these complications is required. Areas covered: We review the multiple infectious and noninfectious lung complications that occur both early and late after allogeneic HSCT. This includes the description of these complications, risk factors, diagnostic approach and outcome. A literature search was performed using PubMed-indexed journals. Expert commentary: Multiple lung complications after allogeneic HSCT can be diagnosed concomitantly and require a multidisciplinary approach. A specific clinical evaluation including a precise analysis of a lung CT scan is necessary. Management of these lung complications, especially the noninfectious ones, is impaired by the lack of prospective, randomized control trials, suggesting preventive strategies should be developed.

CALIPSO: A Randomized Controlled Trial of Calfactant for Acute Lung Injury in Pediatric Stem Cell and Oncology Patients

To assess if calfactant reduces mortality among children with leukemia/lymphoma or after hematopoietic cell transplantation (HCT) with pediatric acute respiratory distress syndrome (PARDS), we conducted a multicenter, randomized, placebo-controlled, double-blinded trial in 17 pediatric intensive care units (PICUs) of tertiary care children's hospitals. Patients ages 18 months to 25 years with leukemia/lymphoma or having undergone HCT who required invasive mechanical ventilation for bilateral lung disease with an oxygenation index (OI) > 10 and <37 were studied. Interventions used were intratracheal instillation of either calfactant or air placebo (1 or 2 doses). Forty-three subjects were enrolled between November 2010 and June 2015: 26 assigned to calfactant and 17 to placebo. There were no significant differences in the primary outcome, which was survival to PICU discharge (adjusted hazard ratio of mortality for calfactant versus placebo, 1.78; 95% confidence interval, .53 to 6.05; P = .35), OI, functional outcomes, or ventilator-free days, adjusting for risk strata and Pediatric Risk of Mortality (PRISM) score. Despite the risk-stratified randomization, more allogeneic HCT patients received calfactant (76% and 39%, respectively) due to low recruitment at various sites. This imbalance is important because independent of treatment arm and while adjusting for PRISM score, those with allogeneic HCT had a nonsignificant higher likelihood of death at PICU discharge (adjusted odds ratio, 3.02; 95% confidence interval, .76 to 12.06; P = .12). Overall, 86% of the patients who survived to PICU discharge also were successfully discharged from the hospital. These data do not support the use of calfactant among this high mortality group of pediatric leukemia/lymphoma and/or HCT patients with PARDS to increase survival. In spite of poor enrollment, allogeneic HCT patients with PARDS appeared to be characterized by higher mortality than even other high-risk immunosuppressed groups. Conducting research among these children is challenging but necessary, because survival to PICU discharge usually results in successful discharge to home.

Respiratory failure in the hematopoietic stem cell transplant recipient

The number of patients receiving hematopoietic stem cell transplantation (HSCT) is rapidly rising worldwide. Despite substantial improvements in peri-transplant care, pulmonary complications resulting in respiratory failure remain a major contributor to morbidity and mortality in the post-transplant period, and represent a major barrier to the overall success of HSCT. Infectious complications include pneumonia due to bacteria, viruses, and fungi, and most commonly occur during neutropenia in the early post-transplant period. Non-infectious complications include idiopathic pneumonia syndrome, peri-engraftment respiratory distress syndrome, diffuse alveolar hemorrhage, pulmonary veno-occlusive disease, delayed pulmonary toxicity syndrome, cryptogenic organizing pneumonia, bronchiolitis obliterans syndrome, and post-transplant lymphoproliferative disorder. These complications have distinct clinical features and risk factors, occur at differing times following transplant, and contribute to morbidity and mortality.

Diffuse alveolar hemorrhage is most often fatal and is affected by graft source, conditioning regimen toxicity, and engraftment kinetics

Diffuse alveolar hemorrhage after hematopoietic stem cell transplantation is a frequently fatal complication with no standard therapy. Although significant changes in supportive and intensive care measures for patients undergoing hematopoietic stem cell transplantation have been made over the past decades, the impact of these changes on the incidence and outcome of patients with diffuse alveolar hemorrhage has not been examined. We analyzed 1228 patients who underwent allogeneic hematopoietic stem cell transplantation between 2008-2015 at the University of Minnesota to study the incidence, risk factors, and outcomes of diffuse alveolar hemorrhage. Diffuse alveolar hemorrhage developed in 5% of allogeneic hematopoietic stem cell transplant recipients, at a median of 30 days (range +3 to +168 days) after transplantation. The incidence of diffuse alveolar hemorrhage was significantly greater in recipients of umbilical cord blood than peripheral blood or bone marrow grafts (HR: 2.08, 95% CI: 1.16-3.74; P=0.01). In multivariate analysis, delayed neutrophil engraftment or primary graft failure was a risk factor for diffuse alveolar hemorrhage following peripheral blood or bone marrow hematopoietic stem cell transplants (HR: 5.51, 95% CI: 1.26-24; P=0.02) and delayed platelet engraftment was associated with significantly increased diffuse alveolar hemorrhage in umbilical cord blood transplant recipients (HR: 6.96, 95% CI: 2.39-20.29; P<0.05). Myeloablative regimens including total body irradiation were also risk factors for diffuse alveolar hemorrhage (HR: 1.8, 95% CI: 1.03-3.13, P=0.05) in both peripheral blood or bone marrow and umbilical cord blood hematopoietic stem cell transplants (HR: 1.87, 95% CI: 0.95-3.71). Patients with diffuse alveolar hemorrhage had an inferior 6-month treatment-related mortality (HR: 6.09, 95% CI: 4.33-8.56, P<0.01) and 2-year overall survival (HR: 4.16, 95% CI: 3.06-5.64; P<0.01) using either graft source. The etiology of diffuse alveolar hemorrhage is multifactorial, involving lung injury influenced by high-dose total body irradiation, graft source, and delayed engraftment or graft failure. The survival of patients with diffuse alveolar hemorrhage after hematopoietic stem cell transplantation remains poor. Clinical interventions or experimental studies (e.g., cell expansion for umbilical cord blood transplants or thrombopoietin use) that modulate these risk factors may limit the incidence and improve the outcomes of diffuse alveolar hemorrhage.

Diagnostic and Prognostic Plasma Biomarkers for Idiopathic Pneumonia Syndrome after Hematopoietic Cell Transplantation

Idiopathic pneumonia syndrome (IPS) is a noninfectious pulmonary complication after hematopoietic cell transplantation (HCT) and is difficult to diagnose. In 41 patients with IPS, we evaluated 6 candidate proteins in plasma samples at day 7 post-HCT and at onset of IPS to identify potential diagnostic or prognostic biomarkers for IPS. Samples at similar times from 162 HCT recipients without documented infections and 37 HCT recipients with respiratory viral pneumonia served as controls. In multivariable models, a combination of Stimulation-2 (ST2; odds ratio [OR], 2.8; P < .001) and IL-6 (OR, 1.4; P = .025) was the best panel for distinguishing IPS at diagnosis from unaffected controls, whereas tumor necrosis factor receptor 1 (TNFR1; OR, 2.9; P = .002) was the best marker when comparing patients with IPS and viral pneumonia. The areas under the curve of the receiver operating characteristic (ROC) curves for discriminating between IPS and unaffected controls at day 7 post-HCT were .8 for ST2, .75 for IL-6, and .68 for TNFR1. Using estimated sensitivity and specificity values from cutoffs determined with the ROC analysis (cutoff level: ST2, 21 ng/mL; IL-6, 61 pg/mL; TNFR1, 3421 pg/mL), we calculated positive predictive values (PPV) for a range of estimated population prevalence values of IPS. Among the 3 markers, ST2 showed the highest PPV for IPS occurrence. Based on an assumed prevalence of 8%, a positive ST2 test increased likelihood of IPS to 50%. We conclude that a prospective validation study is warranted to determine whether a plasma biomarker panel can aid the noninvasive diagnosis and prognosis of IPS.

Etanercept and Corticosteroid Therapy for the Treatment of Late-Onset Idiopathic Pneumonia Syndrome

Idiopathic pneumonia syndrome (IPS) is a complication of allogeneic hematopoietic stem cell transplantation (HSCT) that typically occurs within the first 100 days after transplantation. Tumor necrosis factor α (TNF-α) has been shown to be a key mediator of IPS, and the TNF-α binding protein etanercept appeared to improve IPS outcomes in small retrospective and prospective studies. IPS also has been observed to occur later (>100 days) after HSCT; however, little is known about the disease course and whether a TNF-α-based therapeutic strategy is efficacious in these patients. To address this question, we performed a retrospective analysis of 23 patients who underwent HSCT between 2004 and 2016 at our institution who developed late-onset IPS and received treatment with etanercept and high-dose corticosteroids (CS). Ten of the 23 patients (43%) attained a complete clinical response to etanercept and CS. Responses were significantly more likely to occur in patients who did not require positive pressure ventilation at the time of diagnosis. Those who responded experienced a durable survival benefit, with a 2-year overall survival of 67%. In the 13 patients (57%) who did not respond to etanercept and CS, the median overall survival was only 13 days (range, 1 to 60 days). The difference in 2-year overall survival between responders and nonresponders was statistically significant (67% versus 0%; P < .001). These results indicate that late-onset IPS carries high mortality, but that treatment with etanercept and CS has activity and can result in long-term survival in some patients. Prompt diagnosis and early institution of therapy before the need for advanced respiratory support is critical for maximizing responses.

Infection with a respiratory virus before hematopoietic cell transplantation is associated with alloimmune-mediated lung syndromes

BACKGROUND

Alloimmune-mediated lung syndromes (allo-LSs) are life-threatening complications after hematopoietic cell transplantation (HCT). Respiratory virus (RV) has been suggested to play a role in the pathogenesis.

OBJECTIVE

We studied the relation between RV DNA/RNA detection in the upper/lower airways before HCT and the occurrence of allo-LSs.

METHODS

We retrospectively analyzed all HCT recipients between 2004 and 2014, in whom real-time PCR for RV was performed in nasopharyngeal aspirates (NPAs) and bronchoalveolar lavage (BAL) fluid before HCT. The main outcome of interest was the presence of an allo-LS, which was defined as idiopathic pneumonia syndrome or bronchiolitis obliterans syndrome. Other outcomes were overall survival and treatment-related mortality. We used Cox proportional hazard models, logistic regression models, and Fine-Gray competing risk regression for analyses.

RESULTS

One hundred seventy-nine children (median age, 6.8 years) were included. RVs were found in 61% (41% in BAL fluid/NPAs and 20% in NPAs only). Rhinovirus was the most frequently detected RV (42%). Allo-LSs occurred in 13%. RV positivity in BAL fluid was a predictor for allo-LSs (hazard ratio, 3.8; 95% CI, 1.4-10.7; P = .01), whereas RV positivity in NPAs only was not. No other predictors were found. Grade II to IV acute graft-versus-host disease related to steroid treatment shows a trend toward a protective effect (odds ratio, 0.16; 95% CI, 0.0-1.3; P = .08). Allo-LSs significantly increased treatment-related mortality (52% ± 10% in allo-LSs and 20% ± 4% in non-allo-LSs, P = .007).

CONCLUSIONS

These results show that pre-HCT BAL fluid RV positivity was a predictor for allo-LSs. Screening for RVs before HCT might identify patients at risk for allo-LSs. This could have implications for prevention and treatment and might subsequently influence the outcomes of HCT.

Risk Factors and Outcomes Related to Pediatric Intensive Care Unit Admission after Hematopoietic Stem Cell Transplantation: A Single-Center Experience

To describe incidence, causes, and outcomes related to pediatric intensive care unit (PICU) admission for patients undergoing hematopoietic stem cell transplantation (HSCT), we investigated the risk factors predisposing to PICU admission and prognostic factors in terms of patient survival. From October 1998 to April 2015, 496 children and young adults (0 to 23 years) underwent transplantation in the HSCT unit. Among them, 70 (14.1%) were admitted to PICU. The 3-year cumulative incidence of PICU admission was 14.3%. The main causes of PICU admission were respiratory failure (36%), multiple organ failure (16%), and septic shock (13%). The overall 90-day cumulative probability of survival after PICU admission was 34.3% (95% confidence interval, 24.8% to 47.4%). In multivariate analysis, risk factors predisposing to PICU admission were allogeneic HSCT (versus autologous HSCT, P = .030) and second or third HSCT (P = .018). Characteristics significantly associated with mortality were mismatched HSCT (P = .011), relapse of underlying disease before PICU admission (P < .001), acute respiratory distress syndrome at admission (P = .012), hepatic failure at admission (P = .021), and need for invasive ventilation during PICU course (P < .001). Our data indicate which patients have a high risk for PICU admission after HSCT and for dismal outcomes after PICU stay. These findings may provide support for the clinical decision-making process on the opportunity of PICU admission for severely compromised patients after HSCT.

The Blood and Marrow Transplant Clinical Trials Network: An Effective Infrastructure for Addressing Important Issues in Hematopoietic Cell Transplantation

Hematopoietic cell transplantation (HCT) is a rapidly evolving field with active preclinical and clinical development of new strategies for patient assessment, graft selection and manipulation, and pre- and post-transplantation drug and cell therapy. New strategies require evaluation in definitive clinical trials; however, HCT trials face unique challenges, including the relatively small number of transplantations performed at any single center, the diverse indications for HCT requiring dissimilar approaches, the complex nature of the intervention itself, the risk of multiple complications in the immediate post-transplantation period, and the risk of important, though infrequent, late effects. The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) was established by the US National Heart Lung and Blood Institute and the National Cancer Institute to meet these challenges. In its 15 years as a network, the BMT CTN has proven to be a successful infrastructure for planning, implementing, and completing such trials and for providing definitive answers to questions leading to improvements in the understanding and practice of HCT. It has opened 37 trials, about one-half phase 2 and one-half phase 3, enrolled more than 8000 patients, and published 57 papers addressing important issues in the treatment of patients with life-threatening malignant and nonmalignant blood disorders. This review describes the network's accomplishments, key components of its success, lessons learned over the past 15 years, and challenges for the future.

Decline in the Use of Surgical Biopsy for Diagnosis of Pulmonary Disease in Hematopoietic Cell Transplantation Recipients in an Era of Improved Diagnostics and Empirical Therapy

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Use of biopsy for diagnosis of post-HCT lung disease has declined significantly.

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Improved testing and increased azole use are associated with this decrease.

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Less invasive methods have improved diagnostics for respiratory pathogens.

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We outline an algorithm for appropriate use of lung biopsy in these patients.

Historically, diagnosis of enigmatic pulmonary disease after hematopoietic cell transplantation (HCT) required lung biopsy, but recent advancements in diagnosis and therapy for respiratory infections have changed how clinicians approach pulmonary abnormalities. We examined temporal trends in the use of lung biopsy after HCT. We retrospectively reviewed patients who underwent their first allogeneic HCT at the Fred Hutchinson Cancer Research Center between the years 1993 to 1997, 2003 to 2007, and 2013 to 2015 and subsequently underwent surgical lung biopsy for any reason. Lung biopsy between cohorts were analyzed using a Cox proportional hazards model with death and relapse considered competing risks. Of 1418 patients, 52 (3.7%) underwent 54 post-HCT surgical lung biopsies during 1993 to 1997 compared with 24 (2.1%) and 25 biopsies in the 2003 to 2007 cohort; 2 cases of surgical lung biopsies out of 786 HCT recipients occurred during the 2013 to 2015 cohort (.25%). The median time to biopsy post-HCT was 71.5 days (IQR, 31 to 89) for the early cohort and 97 days (IQR, 42 to 124) for the late cohort, for an overall biopsy incidence of .15 and .075 per 1000 patient days in the first year after HCT, respectively. Patients in the 2003 to 2007 cohort were less likely to undergo a lung biopsy (adjusted HR, .50; 95% CI, .29 to .83; P = .008) when compared with patients in the early cohort, but more patients in the early cohort underwent lung biopsy without antecedent bronchoscopy (25/54 [46%] versus 3/25 [12%], P = .005). Although infections were a more common finding at biopsy in the early cohort (35/1418 versus 8/1148, P < .001), the number of biopsies demonstrating noninfectious lesions was similar between the two cohorts (19/1418 versus 17/1148, P = .76). Fungal infections were the major infectious etiology in both cohorts (32/35 [91%] versus 5/8 [63%], P = .07), but there was a significant reduction in the number of Aspergillus species found at biopsy between the cohorts (30/54 versus 1/25, P < .001). A similar percentage underwent biopsy with therapeutic intent for invasive fungal disease in the 2 cohorts (8/54 [15%] versus 4/25 [16%]). Surgical evaluation of lung disease in HCT recipients significantly declined over a span of 2 decades. The decline from the years 1993 to 1997 compared with 2003 to 2007 was because of a reduction in the number of biopsies for post-transplant infections due to aspergillosis, which is temporally related to improved diagnostic testing by minimally invasive means and the increased use of empiric therapy with extended-spectrum azoles. This practice of primary nonsurgical diagnostic and treatment approaches to pulmonary disease post-HCT have continued, shown by low numbers of surgical biopsies over the last 3 years.

Severe infections in neutropenic patients

PURPOSE OF REVIEW

Severe infections in neutropenic patients can rapidly progress to septic shock and multiorgan failure with a high associated mortality. In this article we discuss current practice, emerging trends and controversies, including the prophylactic and empiric use of antimicrobial therapy, and advances in cellular and immunotherapy.

RECENT FINDINGS

Neutropenia is no longer a consistent factor predicting poor outcome in haematological patients admitted to the ICU. Severe infections in neutropenic patients are often polymicrobial, and pathogen resistance remains a challenge. Invasive fungal infection is still predictive of poor outcome. There has been a rapid expansion in the diagnostics and treatment modalities available for patients with invasive fungal infection. Use of growth factors, polyvalent immunoglobulin, and cellular therapy appear to be of value in certain groups of patients. There is a move away from the use of noninvasive ventilation and the use of high-flow nasal oxygen therapy is one of a number of novel respiratory support strategies that is yet to be evaluated in this patient population.

SUMMARY

Translation of current advances in antimicrobial, cellular and immunotherapy, and diagnostics to aid clinical management by the bedside is important in reducing morbidity and mortality for neutropenic patients with severe infection.

Proteome Profiling in Lung Injury after Hematopoietic Stem Cell Transplantation

Pulmonary complications due to infection and idiopathic pneumonia syndrome (IPS), a noninfectious lung injury in hematopoietic stem cell transplant (HSCT) recipients, are frequent causes of transplantation-related mortality and morbidity. Our objective was to characterize the global bronchoalveolar lavage fluid (BALF) protein expression of IPS to identify proteins and pathways that differentiate IPS from infectious lung injury after HSCT. We studied 30 BALF samples from patients who developed lung injury within 180 days of HSCT or cellular therapy transfusion (natural killer cell transfusion). Adult subjects were classified as having IPS or infectious lung injury by the criteria outlined in the 2011 American Thoracic Society statement. BALF was depleted of hemoglobin and 14 high-abundance proteins, treated with trypsin, and labeled with isobaric tagging for relative and absolute quantification (iTRAQ) 8-plex reagent for two-dimensional capillary liquid chromatography (LC) and data dependent peptide tandem mass spectrometry (MS) on an Orbitrap Velos system in higher-energy collision-induced dissociation activation mode. Protein identification employed a target-decoy strategy using ProteinPilot within Galaxy P. The relative protein abundance was determined with reference to a global internal standard consisting of pooled BALF from patients with respiratory failure and no history of HSCT. A variance weighted t-test controlling for a false discovery rate of ≤5% was used to identify proteins that showed differential expression between IPS and infectious lung injury. The biological relevance of these proteins was determined by using gene ontology enrichment analysis and Ingenuity Pathway Analysis. We characterized 12 IPS and 18 infectious lung injury BALF samples. In the 5 iTRAQ LC-MS/MS experiments 845, 735, 532, 615, and 594 proteins were identified for a total of 1125 unique proteins and 368 common proteins across all 5 LC-MS/MS experiments. When comparing IPS to infectious lung injury, 96 proteins were differentially expressed. Gene ontology enrichment analysis showed that these proteins participate in biological processes involved in the development of lung injury after HSCT. These include acute phase response signaling, complement system, coagulation system, liver X receptor (LXR)/retinoid X receptor (RXR), and farsenoid X receptor (FXR)/RXR modulation. We identified 2 canonical pathways modulated by TNF-α, FXR/RXR activation, and IL2 signaling in macrophages. The proteins also mapped to blood coagulation, fibrinolysis, and wound healing-processes that participate in organ repair. Cell movement was identified as significantly over-represented by proteins with differential expression between IPS and infection. In conclusion, the BALF protein expression in IPS differed significantly from infectious lung injury in HSCT recipients. These differences provide insights into mechanisms that are activated in lung injury in HSCT recipients and suggest potential therapeutic targets to augment lung repair.

Major Pulmonary Complications After Hematopoietic Stem Cell Transplant

Both autologous and allogeneic hematopoietic stem cell transplants are important therapeutic options for several benign and malignant disorders. Pulmonary complications, although they have become less frequent, remain a significant cause of morbidity and mortality after hematopoietic stem cell transplant. These complications range from bacterial, fungal, and viral pulmonary infections to noninfectious conditions such as diffuse alveolar hemorrhage and idiopathic pneumonia syndrome. Bronchiolitis obliterans syndrome is the primary chronic pulmonary complication, and treatment of this condition remains challenging. This report highlights the advances in the diagnosis and management of the major pulmonary complications after hematopoietic stem cell transplant. It also underscores the need for prospective and multicenter research to have a better understanding of the mechanisms behind these complications and to obtain more effective diagnostic tool and therapeutic options.

Fluticasone, Azithromycin, and Montelukast Treatment for New-Onset Bronchiolitis Obliterans Syndrome after Hematopoietic Cell Transplantation

Bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic cell transplantation (HCT) is associated with high mortality. We hypothesized that inhaled fluticasone, azithromycin, and montelukast (FAM) with a brief steroid pulse could avert progression of new-onset BOS. We tested this in a phase II, single-arm, open-label, multicenter study (NCT01307462). Thirty-six patients were enrolled within 6 months of BOS diagnosis. The primary endpoint was treatment failure, defined as 10% or greater forced expiratory volume in 1 second decline at 3 months. At 3 months, 6% (2 of 36, 95% confidence interval, 1% to 19%) had treatment failure (versus 40% in historical controls, P < .001). FAM was well tolerated. Steroid dose was reduced by 50% or more at 3 months in 48% of patients who could be evaluated (n = 27). Patient-reported outcomes at 3 months were statistically significantly improved for Short-Form 36 social functioning score and mental component score, Functional Assessment of Cancer Therapies emotional well-being, and Lee symptom scores in lung, skin, mouth, and the overall summary score compared to enrollment (n = 24). At 6 months, 36% had treatment failure (95% confidence interval, 21% to 54%, n = 13 of 36, with 6 documented failures, 7 missing pulmonary function tests). Overall survival was 97% (95% confidence interval, 84% to 100%) at 6 months. These data suggest that FAM was well tolerated and that treatment with FAM and steroid pulse may halt pulmonary decline in new-onset BOS in the majority of patients and permit reductions in systemic steroid exposure, which collectively may improve quality of life. However, additional treatments are needed for progressive BOS despite FAM.

A call to arms: a critical need for interventions to limit pulmonary toxicity in the stem cell transplantation patient population

Noninfectious pulmonary toxicity after allogeneic hematopoietic stem cell transplantation (allo-HSCT) causes significant morbidity and mortality. Main presentations are idiopathic pneumonia syndrome (IPS) in the acute setting and bronchiolitis obliterans syndrome (BOS) and cryptogenic organizing pneumonia (COP) at later time point. While COP responds well to corticosteroids, IPS and BOS often are treatment refractory. IPS, in most cases, is rapidly fatal, whereas BOS progresses over time, resulting in chronic respiratory failure, impaired quality of life, and eventually, death. Standard second-line treatments are currently lacking, and current approaches, such as augmented T cell-directed immunosuppression, B cell depletion, TNF blockade, extracorporeal photopheresis, and tyroskine kinase inhibitor therapy, are unsatisfactory with responses in only a subset of patients. Better understanding of underlying pathophysiology hopefully results in the identification of future targets for preventive and therapeutic strategies along with an emphasis on currently underutilized rehabilitative and supportive measures.

A Critical Care and Transplantation-Based Approach to Acute Respiratory Failure after Hematopoietic Stem Cell Transplantation in Children

Acute respiratory failure contributes significantly to nonrelapse mortality after allogeneic hematopoietic stem cell transplantation. Although there is a trend of improved survival over time, mortality remains unacceptably high. An understanding of the pathophysiology of early respiratory failure, opportunities for targeted therapy, assessment of the patient at risk, optimal use of noninvasive positive pressure ventilation, strategies to improve alveolar recruitment, appropriate fluid management, care of the patient with chronic lung disease, and importantly, a team approach between critical care and transplantation services may improve outcomes.

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Outcomes from acute respiratory failure after hematopoietic stem cell transplantation remain unacceptably high.

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The review focuses on strategies to improve these outcomes.

Idiopathic pneumonia syndrome after hematopoietic cell transplantation: evidence of occult infectious etiologies

Newer diagnostic methods may link more idiopathic pneumonia syndrome (IPS) cases to an infectious agent. Bronchoalveolar lavage (BAL) samples from 69 hematopoietic cell transplant (HCT) recipients with IPS diagnosed between 1992 and 2006 were tested for 28 pathogens (3 bacteria and 25 viruses) by quantitative polymerase chain reaction and for Aspergillus by galactomannan assay. Research BALs from 21 asymptomatic HCT patients served as controls. Among 69 HCT patients with IPS, 39 (56.5%) had a pathogen detected. The most frequent pathogens were human herpesvirus-6 (HHV-6) (N = 20 [29%]) followed by human rhinovirus (HRV), cytomegalovirus (CMV), and Aspergillus (N = 8 [12%] in each). HHV-6 and HRV were rarely detected in controls, whereas CMV and Aspergillus were occasionally detected with low pathogen load. Patients with pathogens had worse day-100 survival than those without (hazard ratio, 1.88; P = .03). Mortality in patients with only pathogens of "uncertain" significance in lung was similar to that in patients with pathogens of "established" significance. Metagenomic next-generation sequencing did not reveal additional significant pathogens. Our study demonstrated that approximately half of patients with IPS had pathogens detected in BAL, and pathogen detection was associated with increased mortality. Thus, an expanded infection detection panel can significantly increase the diagnostic precision for idiopathic pneumonia.

Lung parenchyma-derived IL-6 promotes IL-17A-dependent acute lung injury after allogeneic stem cell transplantation

Idiopathic pneumonia syndrome (IPS) is a relatively common, frequently fatal clinical entity, characterized by noninfectious acute lung inflammation following allogeneic stem cell transplantation (SCT), the mechanisms of which are unclear. In this study, we demonstrate that immune suppression with cyclosporin after SCT limits T-helper cell (Th) 1 differentiation and interferon-γ secretion by donor T cells, which is critical for inhibiting interleukin (IL)-6 generation from lung parenchyma during an alloimmune response. Thereafter, local IL-6 secretion induces donor alloantigen-specific Th17 cells to preferentially expand within the lung, and blockade of IL-17A or transplantation of grafts lacking the IL-17 receptor prevents disease. Studies using IL-6(-/-) recipients or IL-6 blockade demonstrate that IL-6 is the critical driver of donor Th17 differentiation within the lung. Importantly, IL-6 is also dysregulated in patients undergoing clinical SCT and is present at very high levels in the plasma of patients with IPS compared with SCT recipients without complications. Furthermore, at the time of diagnosis, plasma IL-6 levels were higher in a subset of IPS patients who were nonresponsive to steroids and anti-tumor necrosis factor therapy. In sum, pulmonary-derived IL-6 promotes IPS via the induction of Th17 differentiation, and strategies that target these cytokines represent logical therapeutic approaches for IPS.

TNF-receptor inhibitor therapy for the treatment of children with idiopathic pneumonia syndrome. A joint Pediatric Blood and Marrow Transplant Consortium and Children's Oncology Group Study (ASCT0521)

Idiopathic pneumonia syndrome (IPS) is an acute, noninfectious lung disorder associated with high morbidity and mortality after hematopoietic cell transplantation. Previous studies have suggested a role for TNFα in the pathogenesis of IPS. We report a multicenter phase II trial investigating a soluble TNF-binding protein, etanercept (Enbrel, Amgen, Thousand Oaks, CA), for the treatment of pediatric patients with IPS. Eligible patients were < 18 years old, within 120 days after transplantation, and with radiographic evidence of a diffuse pneumonitis. All patients underwent a pretherapy broncho-alveolor lavage (BAL) to establish the diagnosis of IPS. Systemic corticosteroids (2.0 mg/kg/day) plus etanercept (.4 mg/kg twice weekly × 8 doses) were administered. Response was defined as survival and discontinuation of supplemental oxygen support by day 28 of study. Thirty-nine patients (median age, 11 years; range, 1 to 17) were enrolled, with 11 of 39 patients nonevaluable because of identification of pathogens from their pretherapy BAL. In the remaining 28 patients, the median fraction of inspired oxygen at study entry was 45%, with 17 of 28 requiring mechanical ventilation. Complete responses were seen in 20 (71%) patients, with a median time to response of 10 days (range, 1 to 24). Response rates were higher for patients not requiring mechanical ventilation at study entry (100% versus 53%, P = .01). Overall survival at 28 days and 1 year after therapy were 89% (95% confidence interval [CI], 70% to 96%) and 63% (95% CI, 42% to 79%), respectively. Plasma levels of proinflammatory cytokines were significantly increased at onset of therapy, subsequently decreasing in responding patients. The addition of etanercept to high-dose corticosteroids was associated with high response rates and survival in children with IPS.