title: Early pathologic findings of bronchiolitis obliterans after allogeneic hematopoietic stem cell transplantation: a proposal from a case.
abstract: Bronchiolitis obliterans (BO) is one of the serious, noninfectious pulmonary complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Early diagnosis of BO is usually difficult because patients are often asymptomatic at an initial stage of the disease and pathologic findings are available mostly at the late stages. Therefore, the diagnosis of the disease is based on the pulmonary function test using the National Institute of Health consensus criteria. Here, we report a case of slowly progressive BO. A biopsy specimen at an early stage demonstrated alveolar destruction with lymphocyte infiltration in bronchial walls and mild narrowing of bronchioles without fibrosis, those were strongly indicative of initial pathologic changes of BO. Definitive BO followed, which was proven by both clinical course and autopsy. While alloreactive lymphocytes associated with chronic graft-versus-host disease are believed to initiate BO, we present a rare case that directly implies such a scenario.
authors.affiliation: Department of Hematology, Faculty of Medicine and Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tenoudai Tsukuba, Ibaraki 305-8575, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Nakamoto-Matsubara
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Nishikii
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamada
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ito
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: Naoki
authors.initials: N
authors.lastname: Kurita
authors.forename: Naoshi
authors.initials: N
authors.lastname: Obara
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Okoshi
authors.forename: Kazumi
authors.initials: K
authors.lastname: Suzukawa
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Yokoyama
authors.forename: Mamiko
authors.initials: M
authors.lastname: Sakata-Yanagimoto
authors.forename: Masayuki
authors.initials: M
authors.lastname: Noguchi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Chiba