Pulmonary complications of bone marrow transplantation

Early detection of pulmonary complications can improve outcomes for patients with hematological malignancy (HM). For detecting lung injuries, lung ultrasound (LUS) images have been found to be of greater sensitivity than radiographic images. Our group performed a pilot study of LUS imaging to enhance early detection of pulmonary complications in HM patients. This prospective single-center feasibility study evaluated LUS for detecting pulmonary complications in 18 HM patients enrolled while hospitalized for a hematopoietic cell transplant (HCT) (concurrent-HCT group) or re-hospitalized for complications (post-HCT group). Serial LUS exams were performed and assigned a score from 0 to 5 based on pleural line, B-line, consolidation and pleural effusion features. Correlations between patients’ clinical characteristics and LUS features were analyzed. Comparisons between the LUS and radiographic images were evaluated. In the concurrent-HCT patients (79 LUS exams), non-significant fluctuating findings were commonly identified, but one-third of the patients presented pathologic findings (LUS scores ≥ 3). In the post-HCT patients (29 LUS exams), LUS images revealed severe pathologic findings (LUS score = 5) in every patient and, compared with radiographic images, were more sensitive for detecting pleural effusions (p < 0.05). LUS can be routinely performed on hospitalized HM patients, allowing point-of-care early detection of pulmonary complications.

Pulmonary complications after hematopoietic cell transplantation (HCT) can lead to significant morbidity and mortality. Limited evaluation of the true incidence of these complications in children and subsequent outcomes of these complications have not been evaluated recently. In April 2018, the National Heart, Lung, and Blood Institute; the Eunice Kennedy Shriver National Institute of Child Health and Human Development; and the National Cancer Institute cosponsored a meeting of experts to describe the status of pulmonary complications in children after HCT, identify critical gaps in knowledge, and explore avenues for research to advance care and optimize outcomes. The Center for International Blood and Marrow Transplant Research was used to evaluate the cumulative incidence of pulmonary complications in children and their respective survival. Of the 5022 children included in this analysis who received allogeneic HCT from 2010 to 2016, 606 developed pulmonary complications within the first year after HCT. Pneumonitis occurred in 388 patients, 125 patients developed pulmonary hemorrhage, and 200 patients had lung graft-versus-host disease (GVHD). For those developing pulmonary complications within 1 year, overall survival 100 days after diagnosis of pulmonary complications was 49% (95% confidence interval [CI], 43% to 54%) for patients with pneumonitis, 23% (95% CI, 16% to 31%) in patients with pulmonary hemorrhage, and 87% (95% CI, 81% to 91%) in patients with pulmonary GVHD. This study demonstrates the approximate incidence of these complications, as well as their significant effects on survival, and can serve as a baseline for future research.

Despite clinical advances, late onset pulmonary complications in adult recipients of allogenic stem cell transplantation are a major cause of morbidity and mortality. Reported incidence and risk factors in the literature vary broadly and are partly contradictory. Identification of pretransplant factors associated with major complications would be helpful to define individual treatment strategies and early initiation of preventive measures.

To evaluate incidence and risk factors of late onset noninfectious pulmonary complications, with special regard to small airways disease (SAD) and bronchiolitis obliterans syndrome (BOS), indicating graft-versus-host disease, following myeloablative versus nonmyeloablative allogenic stem cell transplantation.

We reviewed the clinical records and assessed the course of lung function and pulmonary complications in adults who underwent allogenic stem cell transplantation for hematological malignancies between 1999 and 2015 using nonmyeloablative (n = 179) or myeloablative (n = 130) conditioning at the Division of Hematology of the Medical University of Graz. All patients underwent body plethysmography pulmonary function test (PFT), diffusion capacity for carbon monoxide, and arterial blood gas analysis before and repeatedly after transplant. SAD was defined as maximal expiratory flow at 50% and 25% of forced vital capacity <70% predicted.

Ventilatory disorders and gas transfer abnormalities were common before and after allogenic stem cell transplantation, independent of conditioning regimen. SAD was common in the nonmyeloablative (34%) and myeloablative (29%) groups. The 100-day post-transplant mortality was significantly associated with reduced pretransplant total lung capacity <80%. Mortality 100 days post-transplant was significantly associated with pretransplant SAD and a pretransplant smoking history. In this subset, a smoking history was independently associated with increased mortality, with a 5-year mortality of 45% compared with 26% in never-smokers. Pretransplant SAD was not predictive for the later development of BOS.

Smoking history, pretransplant restrictive PFT, and pre-existing SAD are important risk factors for death following allogenic stem cell transplantation. However, pretransplant SAD is not a predictor of long-term complications, including BOS.

The use of antithymocyte globulin (ATG) in hematopoietic stem cell transplantation (HSCT) conditioning regimens has reduced the incidence of graft-versus-host disease, particularly in its chronic form. The impact of this approach on the prevention of lung dysfunction has not been well characterized, however. We performed a retrospective analysis of pulmonary function in patients who underwent HSCT after conditioning with oral busulfan followed by either cyclophosphamide or fludarabine with or without the addition of ATG. A total of 393 patients were included; 75 patients received ATG, and 318 did not. No differences between the 2 groups were seen in the mean percentage of the predicted values for forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC), total lung capacity, and lung CO diffusing capacity at 80 days or 1 year after transplantation. However, the mean value of FEV₁/FVC ratio at 1 year was higher in the patients who received ATG. The difference in mean change in pulmonary function parameters from baseline to 1 year post-HSCT was statistically nonsignificant for all parameters except FEV₁/FVC ratio, which demonstrated less decline in the ATG group. The risk of developing severe airflow obstruction or a restrictive pattern was similar in the 2 treatment groups at 1 year post-HSCT. Incorporation of ATG into the HSCT conditioning regimen provided protection against a decline in FEV₁/FVC ratio but did not decrease the risk of other pulmonary events that we evaluated within the first year after HSCT. Further evaluations in larger numbers of patients are needed to better clarify the role of ATG in the development of delayed pulmonary complications.

We aimed to compare chest low-dose computed tomography (LDCT) with chest radiography (CXR) in the assessment of febrile acute myeloid leukaemia neutropenic patients.

A prospective non-randomized study was carried out between 30 May, 2003 and 3 June, 2004 in consecutive neutropenic patients who required imaging of the thorax and were treated for acute myeloid leukaemia. Each patient had a baseline 2-view chest radiograph followed by LDCT. Both the CXR and the LDCT studies were blindly and independently reviewed by two chest radiologists.

Forty patients were enrolled: 24 male and 16 female, mean age 53.5 years (range 18–83) and an average neutrophil count of 0.78 × 10⁹/L. Patients had CXR within a mean of 40 min from the LDCT. Overall, 31 (77.5%) of 40 CXR were abnormal, whereas LDCT detected abnormalities in 38 (95%) of 40 patients. LDCT demonstrated three times the number of lung nodules as CXR and twice as many ground-glass opacities. Lung consolidation was detected similarly using both techniques, but LDCT demonstrated more extensive and multi-focal consolidation. The majority of nodules detected only on LDCT were subcentimetre in diameter. The additional information provided by LDCT led to an alteration in the clinical management of 11 (27.5%) of 40 patients.

LDCT is a useful tool in the initial investigation of suspected pulmonary complication in neutropenic patients. This is supported by the additional information it provides to the CXR with reduced radiation when compared to conventional CT.