Bronchiolitis Obliterans Syndrome After Allogeneic Hematopoietic Stem Cell Transplantation—An Increasingly Recognized Manifestation of Chronic Graft-versus-Host Disease

Abstract

Bronchiolitis obliterans syndrome (BOS) is a progressive, insidious, and often fatal lung allo-reaction that can occur following allogeneic hematopoietic stem cell transplantation (HCT) or allogeneic lung transplantation. Current estimates in the literature suggest that approximately 2–3% of all allogeneic HCT recipients and 6% of patients who develop chronic GVHD will develop this syndrome. However, based on newer data it is likely that the true incidence of BOS is higher. Unfortunately, the survival and treatment of patients with BOS after HCT has not improved over the last 20 years. Attempts at clinical trials have been hindered by the lack of uniform diagnostic criteria and inability to detect the syndrome at a reversible stage in its natural history. Recently, the NIH consensus project for criteria in chronic GVHD has made recommendations regarding the diagnosis of BOS and monitoring of lung disease among long term survivors. Although a rare and poorly understood manifestation of chronic GVHD, BOS occurs commonly after lung transplantation and is similar in pathology, clinical presentation, radiographic presentation, and presumed immunologic pathogenesis. This review describes the current understanding of the epidemiology and pathogenesis of BOS and presents information on evaluations and therapies for patients with BOS after HCT.

Chest health surveillance utility in the early detection of bronchiolitis obliterans syndrome in children after allo-SCT

“…1 It is characterized by luminal occlusion of the terminal and respiratory bronchioles caused by inflammatory and fibrous tissue formation. In severe cases, the airway develops circumferential scarring with complete obliteration of the lumen, leading to the clinical presentation of cough, shortness of breath or wheezing.…”

Optimal management of chronic graft‐versus‐host disease in children

“…Recommendations for work-up, in addition to PFTs, include high-resolution computer-assisted tomography scan of the chest (with inspiratory and expiratory windows), which would confirm air trapping and lung biopsy (if diagnosis still in question) showing granulation tissue, fibrosis and obliteration of the small airways. Finally, a thorough evaluation to rule out viral, bacterial, fungal and mycobacterial infections (including bronchoalveolar lavage) should be carried out depending on the level of suspicion (Chien et al, 2010).…”

Extracorporeal photopheresis as a new supportive therapy for bronchiolitis obliterans syndrome after allogeneic stem cell transplantation

“…7 This suggests that early diagnosis and new strategies are needed to improve outcomes. Furthermore, as BOS can occur at any time with different clinical course, early diagnosis in asymptomatic patients still remains a challenge.…”

“…4,5 Current treatment of BOS (macrolides, change or increase in immunosuppression-mainly steroids-and inhaled therapy 6 ) still remains unsatisfactory with high mortality rates. 7 Recently, extracorporeal photopheresis (ECP) has been reported as a promising option for treatment of BOS in two case series. 8,9 We report our preliminary experience on 13 chronic GvHD (cGvHD) patients with BOS refractory to standard treatment, treated with ECP in association to standard therapy.…”