Pretransplant pulmonary function predicts cytomegalovirus-associated interstitial pneumonia following bone marrow transplantation

Recovery of Pulmonary Function after Allogeneic Hematopoietic Cell Transplantation in Children is Associated with Improved Survival

Abnormal pulmonary function is prevalent in survivors of allogeneic hematopoietic cell transplantation (HCT). Post-transplantation recovery of pulmonary function, and its effect on survival, in children are not known. This retrospective cohort study of 308 children followed for 10 years after HCT at a single institution included 2 groups of patients. Group 1 comprised 188 patients with 3 or more pulmonary function test (PFT) results, of which at least 1 was abnormal, and group 2 comprised 120 patients with 3 or more PFTs, all of which were normal. Pulmonary function normalized post-transplantation in 51 patients (27%) in group 1. Obstructive lung disease, restrictive lung disease, mixed lung disease, and normal pattern were seen in 43%, 25%, 5%, and 27% of patients, respectively, at a median of 5 years (range, 0.5 to 11.9 years) post-transplantation. Lung volumes recovered better than spirometric indices. Pulmonary complications were seen in 80 patients (43%) in group 1. Patients who recovered pulmonary function had better overall survival (P = .006), which did not differ significantly from that in patients in group 2 with normal lung function post-transplantation (P = .80). After adjusting for duration of follow-up, pulmonary complications (P = .01), and lower pretransplantation forced vital capacity z-scores (P = .01) were associated with poor recovery. T cell depletion (P < .001), lower pretransplantation forced expired volume in 1 second z-scores (P = .006), and chronic graft-versus-host disease (P < .001) increased the risk for pulmonary complications. Nonrecovery of lung function with pulmonary complications (P = .03), acute graft-versus-host disease (P = .004), and mechanical ventilation (P < .001) were risk factors for nonrelapse mortality. Normalization of pulmonary function is possible in long-term survivors of allogeneic HCT. Strategies to decrease the risk of pulmonary complications may improve outcomes.

Pre-hematopoietic stem cell transplant lung function and pulmonary complications in children

RATIONALE

Pulmonary complications are a significant cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation.

OBJECTIVES

The relationship between pretransplant pulmonary function tests (PFTs) and development of post-transplant pulmonary complications in children was studied.

METHODS

This is a retrospective single institution cohort study of 410 patients who underwent pretransplant PFT and were monitored to 10 years posttransplant.

MEASUREMENTS AND MAIN RESULTS

Pulmonary complications were observed in 174 (42%) patients. Children with pulmonary complications had significantly lower forced expiratory flow at 25-75% of vital capacity (P = 0.02) derived using conventional predicted equations for age, and the Global Lung Initiative-2012 predicted equations (P = 0.01). T-cell depletion (P = 0.001), acute grade 3-4 graft-versus-host disease (P = 0.008), and chronic graft-versus-host disease (P = 0.01) increased risk for pulmonary complications. Patients who had pulmonary complications had a 2.8-fold increased risk of mortality (P < 0.0001). The cumulative incidence of death due to pulmonary complications was significantly higher in children who had low lung volumes, FRC less than 50% (P = 0.005), TLC less than 50% (P = 0.0002), residual volume less than 50% (P = 0.007), and T-cell depletion (P = 0.01). Lower FEV1 (P = 0.0005), FVC (P = 0.0005), TLC (P  <  0.0001), residual volume less than 50% (P = 0.01), and restrictive lung disease (P = 0.01) predicted worse overall survival.

CONCLUSIONS

Abnormal pretransplant PFT significantly increased risk after transplant. These patients may benefit from modified transplant strategies to reduce morbidity and mortality.

Pulmonary function testing prior to reduced intensity conditioning allogeneic stem cell transplantation in an unselected patient cohort predicts posttransplantation pulmonary complications and outcome

Pretransplant pulmonary function tests (PFTs) have been checked mostly in myeloablative allogeneic stem cell transplantation (Allo-SCT). Their value in the setting of reduced intensity conditioning Allo-SCT (Allo-RIC) has been less explored. We retrospectively evaluated the predictive value of PFTs on posttransplant pulmonary complications (PPC) and outcomes in 195 consecutive Allo-RIC patients, based on fludarabine plus busulphan or melphalan. PFT parameters included forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1/FVC ratio, total lung capacity (TLC), residual volume, and diffusion capacity for carbon monoxide (DLCo) corrected for the hemoglobin levels. Pretransplant PFTs abnormalities were observed in 130 patients (66%). The most frequent abnormalities were abnormal DLCO (n = 83, 44%), followed by FEV1/FVC (n = 75, 38%) and FVC (n = 47, 24%). The abnormalities were severe in 25 (13%) patients, moderate in 65 (33%) and mild in 40 patients (21%). Multivariate analysis showed that TLC was significantly associated with PPC, nonrelapse mortality and overall survival (OS), (HR 4.2, 95% CI. 2-8.5; HR 3.8, 95% CI. 1.7-8.5; HR 2.3, 95% CI. 1.3-4.1, respectively, P = 0.01), while abnormal FVC had a negative impact on PPC and OS (HR 1.8, 95% CI. 0.98-3.6, P = 0.06 and HR 1.7, 95% CI. 1.1-2.6, P = 0.008). This study emphasizes the valuable role of PFTs in identifying patients at risk for PPC, NRM, and lower OS in the Allo-RIC setting.

Comorbidities and hematopoietic cell transplantation outcomes

Conventional allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment option for various hematological diseases due, in part to high-dose conditioning and, in part, to graft-versus-tumor effects. Reduced-intensity or non-myeloablative conditioning regimens have relied mostly on graft-versus-tumor effects for disease control, and their advent has allowed relatively older and medically infirm patients to be offered allo-HCT. However, both HCT modalities have been associated with organ toxicities and graft-versus-host disease, resulting in substantial non-relapse mortality. It has become increasingly important to optimize pre-transplant risk assessment in order to improve HCT decision making and clinical trial assignments. Single-organ comorbidity involving liver, lung, heart, or kidney before HCT has been traditionally found to cause organ toxicity after HCT. Recent efforts have resulted in the advent of a weighted scoring system that could sensitively capture multiple-organ comorbidities prior to HCT. The HCT-comorbidity index (HCT-CI) has provided better prediction of HCT-related morbidity and mortality than other non-HCT-specific indices. Subsequent studies, with the exception of a few studies with modest numbers of patients, have confirmed the prognostic importance of the HCT-CI. Further, the HCT-CI has been consolidated with various disease-specific and patient-specific risk factors to refine assignments of patients to the appropriate HCT setting. Ongoing studies are addressing prospective validation of the HCT-CI, furthering our understanding of biological aging, and enhancing the applicability of the HCT-CI comorbidity coding. Future knowledge of the impacts of multiple comorbidities on post-HCT toxicities might guide new prophylactic and therapeutic interventions to lessen the procedure's mortality.

Influence of pretransplantation restrictive lung disease on allogeneic hematopoietic cell transplantation outcomes

We conducted a 15-year retrospective cohort study to determine the prevalence of restrictive lung disease before allogeneic hematopoietic cell transplantation (HCT), and to assess whether this was a risk factor for poor outcomes. A total of 2545 patients were eligible for the analysis. Restrictive lung disease was defined as a total lung capacity (TLC) < 80% of predicted normal. Chest x-rays and /or computed tomography (CT) scans were reviewed for all restricted patients to determine whether lung parenchymal abnormalities were unlikely or highly likely to cause restriction. Multivariate Cox proportional hazard and sensitivity analyses were performed to assess the relationship between restriction and early respiratory failure and nonrelapse mortality. Restrictive lung disease was present in 194 subjects (7.6%) before HCT. Among these cases, radiographically apparent abnormalities were unlikely to be the cause of the restriction in 149 subjects (77%). In unadjusted and adjusted analyses, the presence of pulmonary restriction was significantly associated with a 2-fold increase in risk for early respiratory failure and nonrelapse mortality, suggesting that these outcomes occurring in the absence of radiographically apparent abnormalities may be related to respiratory muscle weakness. These findings suggest that pulmonary restriction should be considered a risk factor for poor outcomes after transplantation.

Carbon monoxide diffusion capacity: how low can you go for hematopoietic cell transplantation eligibility?

Current guidelines suggest that patients with a pretransplantation diffusion capacity of the lung for carbon monoxide (DLCO) < or = 60% are not ideal candidates for hematopoietic cell transplantation (HCT); however, recent studies suggest this criterion may exclude patients who will benefit from the procedure. We conducted a study of all adult patients who underwent autologous or allogeneic HCT between 1990 and 2005, and had a DLCO < 60%, of predicted normal, to examine whether there is a lower limit for the DLCO threshold in the context of respiratory failure and nonrelapse mortality risk (NRM), and whether a comprehensive risk scoring system, such as the Pretransplant Assessment of Mortality (PAM) risk score, can more effectively risk stratify these patients with a very low pretransplantation DLCO. We found that among patients with a DLCO < or = 60% the risk of respiratory failure or NRM was not significantly different; however, the PAM score effectively risk-stratified these patients for NRM risk. There was a stepwise relationship between PAM score category and NRM risk; the highest PAM score category was associated with a 4.38-fold increase in risk (P < .001). These findings suggest that the pretransplantation DLCO should not be considered the sole eligibility criteria for allogeneic HCT.

Manifestations of human cytomegalovirus infection: proposed mechanisms of acute and chronic disease

Infections with human cytomegalovirus (HCMV) are a major cause of morbidity and mortality in humans with acquired or developmental deficits in innate and adaptive immunity. In the normal immunocompetent host, symptoms rarely accompany acute infections, although prolonged virus shedding is frequent. Virus persistence is established in all infected individuals and appears to be maintained by both a chronic productive infections as well as latency with restricted viral gene expression. The contributions of the each of these mechanisms to the persistence of this virus in the individual is unknown but frequent virus shedding into the saliva and genitourinary tract likely accounts for the near universal incidence of infection in most populations in the world. The pathogenesis of disease associated with acute HCMV infection is most readily attributable to lytic virus replication and end organ damage either secondary to virus replication and cell death or from host immunological responses that target virus-infected cells. Antiviral agents limit the severity of disease associated with acute HCMV infections, suggesting a requirement for virus replication in clinical syndromes associated with acute infection. End organ disease secondary to unchecked virus replication can be observed in infants infected in utero, allograft recipients receiving potent immunosuppressive agents, and patients with HIV infections that exhibit a loss of adaptive immune function. In contrast, diseases associated with chronic or persistent infections appear in normal individuals and in the allografts of the transplant recipient. The manifestations of these infections appear related to chronic inflammation, but it is unclear if poorly controlled virus replication is necessary for the different phenotypic expressions of disease that are reported in these patients. Although the relationship between HCMV infection and chronic allograft rejection is well known, the mechanisms that account for the role of this virus in graft loss are not well understood. However, the capacity of this virus to persist in the midst of intense inflammation suggests that its persistence could serve as a trigger for the induction of host-vs-graft responses or alternatively host responses to HCMV could contribute to the inflammatory milieu characteristic of chronic allograft rejection.

Diffusion capacity predicts long-term survival after allogeneic bone marrow transplantation for acute lymphoblastic leukemia

BACKGROUND

The aim of this study was to evaluate changes in pulmonary function measures as predictors of outcome in acute lymphoblastic leukemia (ALL) patients after myeloablative allogeneic bone marrow transplantation (BMT).

METHODS

Forced expiratory volume in 1 second (FEV1) and diffusion capacity for carbon monoxide (DLCO) were evaluated before and after allogeneic BMT every 3 months in 32 patients who survived for at least 100 days. General case histories were also examined.

RESULTS

Univariate analysis revealed that decreased post-BMT DLCO was associated with increased overall and event-free survival (p < 0.05). While a pre-BMT FEV1 of < 70% was associated with significantly decreased overall survival (p < 0.05), multiple regression analysis indicated that patients without cytomegalovirus (CMV) infection, having limited chronic graft-versus-host disease (GVHD) and with markedly decreased DLCO had better overall survival (p < 0.05). After adjusting for age, gender, chronic GVHD, and CMV infection, patients with decreased DLCO exhibited enhanced overall survival. Two-year survival and event-free survival rates were significantly higher in patients with decreased DLCO.

CONCLUSION

We conclude that DLCO may be a good long-term predictor of outcome in patients with ALL following BMT.

Hematopoietic cell transplantation specific comorbidity index as an outcome predictor for patients with acute myeloid leukemia in first remission: combined FHCRC and MDACC experiences

A new hematopoietic cell transplantation-specific comorbidity index (HCT-CI) was effective in predicting outcomes among patients with hematologic malignancies who underwent HCT at Fred Hutchinson Cancer Research Center (FHCRC). Here, we compared the performance of the HCT-CI to 2 other indices and then tested its capacity to predict outcomes among 2 cohorts of patients diagnosed with a single disease entity, acute myeloid leukemia in first complete remission, who underwent transplantation at either FHCRC or M. D. Anderson Cancer Center (MDACC). FHCRC patients less frequently had unfavorable cytogenetics (15% versus 36%) and HCT-CI scores of 3 or more (21% versus 58%) compared with MDACC patients. We found that the HCT-CI had higher sensitivity and outcome predictability compared with the other indices among both cohorts. HCT-CI scores of 0, 1 to 2, and 3 or more predicted comparable nonrelapse mortality (NRM) among FHCRC and MDACC patients. In multivariate models, HCT-CI scores were associated with the highest hazard ratios (HRS) for NRM and survival among each cohort. The 2-year survival rates among FHCRC and MDACC patients were 71% versus 56%, respectively. After adjustment for risk factors, including HCT-CI scores, no difference in survival was detected (HR: 0.98, P = .94). The HCT-CI is a sensitive and informative tool for comparing trial results at different institutions. Inclusion of comorbidity data in HCT trials provides valuable, independent information.

Chronic lung disease after hematopoietic stem cell transplantation

Tens of thousands of patients undergo hematopoietic stem cell transplantation (HSCT) each year, mainly for hematologic disorders. In addition to the underlying diseases, the chemotherapy and radiation therapy that HSCT recipients receive can result in damage to multiple organ systems. Pulmonary complications develop in 30% to 60% of HSCT recipients. With the widespread use of prophylaxis for certain infections, the spectrum of pulmonary complications after HSCT has shifted from more infectious to noninfectious complications. This article reviews some of the noninfectious, chronic pulmonary complications.

Factors predicting success or failure associated with common types of transplants

The ability to predict clinical outcomes is essential to accurate medical decision analysis. Many accepted bone marrow transplant related prognostic variables are derived from data that is over 20-years old and may or may not be applicable to current medical practice. This report reviews both older data concerning bone marrow transplantation prognostic factors as well as more current reports. In addition to pretransplant variables, this review examines easily measured post-transplant variables that may affect prognosis, as well as data concerning the cellular component of the infused graft in both allogeneic and autologous transplantation.

Pulmonary complications following hematopoietic stem cell transplantation: diagnostic approaches

Pulmonary complications are a significant cause of morbidity and mortality in hematopoietic stem cell transplant recipients. Pulmonary infiltrates in such patients pose a major challenge for clinicians because of the wide differential diagnosis of infectious and noninfectious conditions. It is rare for the diagnosis to be made by chest radiograph, and commonly these patients will need further invasive and noninvasive studies to confirm the etiology of the pulmonary infiltrates. This review describes the role of the different diagnostic tools available to reach a diagnosis in a timely manner in this patient population.

Pretransplant lung function, respiratory failure, and mortality after stem cell transplantation

RATIONALE

The role of pulmonary function before stem cell transplant as a potential risk factor for the development of early post-transplant respiratory failure and mortality is controversial.

METHODS

We conducted a retrospective analysis of the pretransplant pulmonary function of 2,852 patients who received their transplant between 1990 and 2001.

MEASUREMENTS

Pretransplant FEV(1), FVC, total lung capacity (TLC), diffusing capacity of carbon monoxide (DL(CO)), and the alveolar-arterial oxygen tension difference P(A-a)O(2) were measured and assessed for association with development of early respiratory failure and mortality in Cox proportional hazard logistic models.

MAIN RESULTS

In multivariate analyses, progressive decrease of all lung function parameters was associated with a stepwise increase in risk of developing early respiratory failure and mortality when assessed in independent models. On the basis of a significant correlation between FEV(1) and FVC (r = 0.81), FEV(1) and TLC (r = 0.61), and FVC and TLC (r = 0.80), and a lack of correlation between FEV(1) and DL(CO), we developed a pretransplant lung function score based on pretransplant FEV(1) and DL(CO) to determine the extent of pulmonary compromise before transplant. Multivariate analysis indicated that higher pretransplant lung function scores are associated with a significant increased risk for developing early respiratory failure (category II hazard ratio [HR], 1.4; category III HR, 2.2; category IV HR, 3.1; p < 0.001) and death (category II HR, 1.2; category III HR, 2.2; category IV HR, 2.7; p < 0.005).

CONCLUSIONS

These results suggest that not only does compromised pretransplant lung function contribute to the risk for development of early respiratory failure and mortality but this risk may be estimated before transplant by grading the extent of FEV(1) and DL(CO) compromise.

Pulmonary complications of solid organ and hematopoietic stem cell transplantation

The ability to successfully transplant solid organs and hematopoietic stem cells represents one of the landmark medical achievements of the twentieth century. Solid organ transplantation has emerged as the standard of care for select patients with severe vital organ dysfunction and hematopoietic stem cell transplantation has become an important treatment option for patients with a wide spectrum of nonmalignant and malignant hematologic disorders, genetic disorders, and solid tumors. Although advances in surgical techniques, immunosuppressive management, and prophylaxis and treatment of infectious diseases have made long-term survival an achievable goal, transplant recipients remain at high risk for developing a myriad of serious and often life-threatening complications. Paramount among these are pulmonary complications, which arise as a consequence of the immunosuppressed status of the recipient as well as from such factors as the initial surgical insult of organ transplantation, the chemotherapy and radiation conditioning regimens that precede hematopoietic stem cell transplantation, and alloimmune mechanisms mediating host-versus-graft and graft-versus-host responses. As the population of transplant recipients continues to grow and as their care progressively shifts from the university hospital to the community setting, knowledge of the pulmonary complications of transplantation is increasingly germane to the contemporary practice of pulmonary medicine.

Prognostic importance of the platelet count 100 days post allogeneic bone marrow transplant

We assessed the prognostic importance of the platelet count 100 days post transplant of 107 consecutive patients receiving ablative allogeneic bone marrow transplant (BMT) between 7/96 and 12/00 who survived at least 100 days. Diagnoses included AML (n=36), chronic myelogenous leukemia (n=27), NHL (n=14), ALL (n=16), MDS (n=9), aplastic anemia (n=3), and one Hodgkin's disease and myelofibrosis each. In total, 64% were in remission or in chronic phase or had aplastic anemia (good risk), and 36% had active disease at the time of transplant (bad risk). In all, 70% were matched sibling transplants and 30% were matched unrelated donor transplants. The mean follow-up for the patients remaining alive is 48 months. Survival was powerfully influenced by the 100-day platelet count: 4-year survival was 19% for patients with a platelet count <30 x 10(9)/l; 41% for patients with a platelet count of 30-50; and 72% for those with a platelet count >50 (P<0.001; log-rank test). In a multivariable analysis, the most powerful risk factors for mortality after allogeneic BMT were low 100-day platelet count (P<0.001) and bad risk disease (P=0.009). We conclude that the platelet count 100 days post transplant is a powerful predictor of overall survival.

Are predictive factors clinically useful in bone marrow transplantation?

Variables that accurately predict the clinical outcome of any procedure, including bone marrow transplantation (BMT), are of paramount importance when assessing the risks and benefits of the procedure. This review of the world's literature of variables affecting overall outcome after myeloablative BMT critically appraises the value of many bone marrow transplant dogmas. There is a relative paucity of data supporting many commonly used transplant practices, including having an upper age limit for eligibility criteria, and absolute requirements for cardiac and pulmonary function pre transplant. In contrast, recently published literature suggests that several parameters occurring soon after a BMT has been performed may accurately predict transplant outcome. Ultimately, given the rapidly evolving nature of BMT, renewed clinical research of variables predictive of transplant outcome is needed.

Alveolar macrophage activity and the pulmonary complications of haematopoietic stem cell transplantation

BACKGROUND

The success of haematopoietic (bone marrow or peripheral blood) stem cell transplantation (SCT) is compromised by pulmonary complications. We hypothesised that a proinflammatory alveolar microenvironment, reflected in alveolar macrophage (AM) cytokine production, would predispose to such complications.

METHODS

AM were isolated from adult SCT recipients by bronchoalveolar lavage before SCT (n=32) and during post-transplant pancytopenia (n=23). Concentrations of tumour necrosis factor (TNF)alpha, granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin (IL)-1 beta, IL-6, and IL-8 in 24 hour AM culture medium were measured by enzyme linked immunosorbent assay and compared with both the occurrence of post-SCT lung disease and with subjects' previous respiratory histories.

RESULTS

Eleven subjects developed lung disease within 6 months of SCT. These subjects had higher median pre-transplant AM TNFalpha (8 (IQR 1-8) v 2 (1-5) ng/10(6)AM, p=0.01, median difference (D) = 3, 95% CI 0.1 to 7), GM-CSF (5 (0.7-8) v 0.2 (0.1-0.8), p=0.006, D = 4, 95% CI 0.5 to 7), and IL-6 (0.5 (0.1-1) v 0.1 (0.02-0.3), p=0.049, D = 0.3, 95% CI 0.0002 to 1) production than remaining subjects; IL-1 beta and IL-8 did not differ. During pancytopenia high AM GM-CSF production again predicted later lung disease (1 (0.7-9) v 0.1 (0.06-0.3), p=0.01, D = 1, 95% CI 0.1 to 6). A history of recent chest disease was associated with high AM TNFalpha and GM-CSF production and with post-SCT lung disease. Pre-SCT lung function was unrelated to post-SCT lung disease.

CONCLUSIONS

Recent respiratory disease and persistent proinflammatory AM behaviour detectable before transplantation are associated with lung disease following SCT. These associations may prove useful in pre-transplant risk assessment.

Bronchiolitis obliterans and other late onset non-infectious pulmonary complications in hematopoietic stem cell transplantation

Pulmonary complications develop in 30-60% of hematopoietic stem cell transplants (HSCT). The main, late onset, non-infectious complications include Bronchiolitis obliterans (BO), Bronchiolitis obliterans organizing pneumonia (BOOP), and idiopathic pneumonia syndrome (IPS). BO and BOOP occur almost exclusively in allogeneic HSCT, and have 61% and 21% mortality rates, respectively. BOOP responds favorably to corticosteroids. IPS has less than 15% 1-year survival.

Critical care of the hematopoietic stem cell patient

Hematopoietic stem cell transplantation is evolving into a treatment modality with expanding indications and volume and with excellent outcomes, although it carries significant risk for morbidity and mortality affecting most major organ systems and often requires ICU care. With continuing improvements in supportive care and specific therapy of complications following HCT including the open-lung strategy of mechanical ventilation, use of nitric oxide, less toxic myeloablative regimens, newer classes of antibiotics, and improved immunosuppression strategies, it is hoped that mortality in this setting will continue to decline in coming years.