title: Decreased exhaled nitric oxide in sickle cell disease: relationship with chronic lung involvement.
abstract: A deficiency in airway nitric oxide (NO) could contribute to pulmonary vaso-occlusion in sickle cell disease (SCD). We measured the fractional expired concentration of NO (FE(NO)) by chemiluminescence during a slow vital capacity maneuver against a positive pressure of 16 cm H(2)O at an expiratory flow rate of 50 mL/sec in 44 stable ambulatory adults with SCD and 30 healthy controls. A history of acute chest syndrome was present in 29 patients, and 22 complained of dyspnea. Mean +/- SD FE(NO) was significantly reduced in the SCD group compared with controls (14.8 +/- 8.4 vs. 24.9 +/- 13.5 ppb, P < 0.001). SCD patients with dyspnea had lower FE(NO) than those without dyspnea (10.1 +/- 5.7 vs. 19.6 +/- 8 ppb, P < 0.001) and those with a history of ACS had lower values than those no episodes of ACS (13.0 +/- 8.3 vs. 18.4 +/- 7.6 ppb, P < 0.05). There was a weak correlation between FE(NO) and percent-predicted DLCO (r = 0.4, P = 0.02) among the SCD patients. We conclude that exhaled NO is reduced in adults with SCD, and this may play a role in the pathogenesis of acute chest syndrome and chronic sickle cell lung disease.
authors.affiliation: Division of Pulmonary, Critical Care and Sleep Medicine, Wayne State University School of Medicine, Detroit, Michigan, USA. rgirgis@jhmi.edu
authors.forename: Reda E
authors.initials: RE
authors.lastname: Girgis
authors.forename: Mohammed A
authors.initials: MA
authors.lastname: Qureshi
authors.forename: Judith
authors.initials: J
authors.lastname: Abrams
authors.forename: Paul
authors.initials: P
authors.lastname: Swerdlow
mesh_terms: D000328:Adult; D000755:Anemia, Sickle Cell / Q000150:complications* / Q000378:metabolism*; D001944:Breath Tests; D002908:Chronic Disease; D004417:Dyspnea / Q000150:complications / Q000378:metabolism; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D006918:Hydroxyurea / Q000627:therapeutic use; D008163:Luminescent Measurements; D008171:Lung Diseases / Q000209:etiology* / Q000378:metabolism; D008297:Male; D009569:Nitric Oxide / Q000032:analysis* / Q000378:metabolism
chemical_list: D006454:Hemoglobins; D009569:Nitric Oxide; D006918:Hydroxyurea