title: The effect of reflux and bile acid aspiration on the lung allograft and its surfactant and innate immunity molecules SP-A and SP-D.
abstract: Gastro-esophageal reflux and related pulmonary bile acid aspiration were prospectively investigated as possible contributors to postlung transplant bronchiolitis obliterans syndrome (BOS). We also studied the impact of aspiration on pulmonary surfactant collectin proteins SP-A and SP-D and on surfactant phospholipids--all important components of innate immunity in the lung. Proximal and distal esophageal 24-h pH testing and broncho-alveolar lavage fluid (BALF) bile acid assays were performed prospectively at 3-month posttransplant in 50 patients. BALF was also assayed for SP-A, SP-D and phospholipids expressed as ratio to total lipids: phosphatidylcholine; dipalmitoylphosphatidylcholine; phosphatidylglycerol (PG); phosphatidylinositol; sphingomyelin (SM) and lysophosphatidylcholine. Actuarial freedom from BOS was assessed. Freedom from BOS was reduced in patients with abnormal (proximal and/or distal) esophageal pH findings or BALF bile acids (Log-rank Mantel-Cox p < 0.05). Abnormal pH findings were observed in 72% (8 of 11) of patients with bile acids detected within the BALF. BALF with high levels of bile acids also had significantly lower SP-A, SP-D, dipalmitoylphosphatidylcholine; PG and higher SM levels (Mann-Whitney, p < 0.05). Duodeno-gastro-esophageal reflux and consequent aspiration is a risk factor for the development of BOS postlung transplant. Bile acid aspiration is associated with impaired lung allograft innate immunity manifest by reduced surfactant collectins and altered phospholipids.
authors.affiliation: Toronto Lung Transplant Program, University of Toronto, Ontario, Canada.
authors.forename: F
authors.initials: F
authors.lastname: D'Ovidio
authors.forename: M
authors.initials: M
authors.lastname: Mura
authors.forename: R
authors.initials: R
authors.lastname: Ridsdale
authors.forename: H
authors.initials: H
authors.lastname: Takahashi
authors.forename: T K
authors.initials: TK
authors.lastname: Waddell
authors.forename: M
authors.initials: M
authors.lastname: Hutcheon
authors.forename: D
authors.initials: D
authors.lastname: Hadjiliadis
authors.forename: L G
authors.initials: LG
authors.lastname: Singer
authors.forename: A
authors.initials: A
authors.lastname: Pierre
authors.forename: C
authors.initials: C
authors.lastname: Chaparro
authors.forename: C
authors.initials: C
authors.lastname: Gutierrez
authors.forename: L
authors.initials: L
authors.lastname: Miller
authors.forename: G
authors.initials: G
authors.lastname: Darling
authors.forename: M
authors.initials: M
authors.lastname: Liu
authors.forename: M
authors.initials: M
authors.lastname: Post
authors.forename: S
authors.initials: S
authors.lastname: Keshavjee
mesh_terms: D001647:Bile Acids and Salts / Q000378:metabolism*; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D005500:Follow-Up Studies; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007113:Immunity, Innate / Q000276:immunology*; D016040:Lung Transplantation / Q000276:immunology*; D010715:Phosphatidylglycerols / Q000378:metabolism; D037662:Pulmonary Surfactant-Associated Protein A / Q000276:immunology*; D037663:Pulmonary Surfactant-Associated Protein D / Q000276:immunology*; D053120:Respiratory Aspiration / Q000503:physiopathology*; D013109:Sphingomyelins / Q000378:metabolism; D014184:Transplantation, Homologous / Q000276:immunology
chemical_list: D001647:Bile Acids and Salts; D010715:Phosphatidylglycerols; D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D013109:Sphingomyelins