title: Small airways function declines after allogeneic haematopoietic stem cell transplantation.
abstract: Bronchiolitis obliterans (BO) following allogeneic haematopoietic stem cell transplantation (HSCT) affects peripheral airways. Detection of BO is presently delayed by the low sensitivity of spirometry. We examined the relationship between peripheral airway function and time since HSCT, and compared it with spirometry and clinical indices in 33 clinically stable allogeneic HSCT recipients. The following measurements were performed: lung function, exhaled nitric oxide, forced oscillatory respiratory system resistance and reactance, acinar (S(acin)) and conductive airways ventilation heterogeneity and lung clearance index (LCI) measured by multiple breath nitrogen washout. 22 patients underwent repeat visits from which short-term changes were examined. Median time post HSCT was 12 months. Eight patients were clinically diagnosed as having BO. In multivariate analysis, time since HSCT was predicted by S(acin) and forced expiratory volume in 1 s % predicted. 20 patients had abnormal S(acin) with normal spirometry, whereas none had airflow obstruction with normal S(acin). S(acin) and LCI were the only measures to change significantly between two visits, with both worsening. Change in S(acin) was the only parameter to correlate with change in chronic graft-versus-host disease grade. In conclusion, peripheral airways ventilation heterogeneity worsens with time after HSCT. S(acin) may be more sensitive than spirometry in detecting BO at an early stage, which needs confirmation in a prospective study.
authors.affiliation: The Woolcock Institute of Medical Research, University of Sydney, New South Wales, Australia. samir.lahzami@chuv.ch
authors.forename: S
authors.initials: S
authors.lastname: Lahzami
authors.forename: R E
authors.initials: RE
authors.lastname: Schoeffel
authors.forename: V
authors.initials: V
authors.lastname: Pechey
authors.forename: C
authors.initials: C
authors.lastname: Reid
authors.forename: M
authors.initials: M
authors.lastname: Greenwood
authors.forename: C M
authors.initials: CM
authors.lastname: Salome
authors.forename: N
authors.initials: N
authors.lastname: Berend
authors.forename: G G
authors.initials: GG
authors.lastname: King
mesh_terms: D000403:Airway Resistance; D001944:Breath Tests; D001989:Bronchiolitis Obliterans / Q000209:etiology*; D005260:Female; D005541:Forced Expiratory Volume; D006086:Graft vs Host Disease / Q000209:etiology / Q000503:physiopathology; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects*; D006801:Humans; D008171:Lung Diseases / Q000209:etiology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D012115:Residual Volume; D014109:Total Lung Capacity; D014184:Transplantation, Homologous; D014797:Vital Capacity
chemical_list: D009569:Nitric Oxide; D009584:Nitrogen