PT - JOURNAL ARTICLE AU - N.R. Labiris AU - C. Nahmias AU - A.P. Freitag AU - M.L. Thompson AU - M.B. Dolovich TI - Uptake of <sup>18</sup>fluorodeoxyglucose in the cystic fibrosis lung: a measure of lung inflammation? AID - 10.1183/09031936.03.00065102 DP - 2003 May 01 TA - European Respiratory Journal PG - 848--854 VI - 21 IP - 5 4099 - http://erj.ersjournals.com/content/21/5/848.short 4100 - http://erj.ersjournals.com/content/21/5/848.full SO - Eur Respir J2003 May 01; 21 AB - Positron emission tomography is a three-dimensional imaging technique that measures physiological effects, including metabolism. 18Fluorodeoxyglucose has been extensively used as a tracer of cellular energy metabolism in the brain and in tumour detection. As neutrophils utilise glucose as an energy source during their respiratory burst, it was hypothesised that 18fluorodeoxyglucose uptake, by these cells, could be interpreted as a measure of neutrophil activation in cystic fibrosis (CF). Ten adult CF patients were given a bolus intravenous injection of 18fluorodeoxyglucose, followed by a 90-min dynamic mid-lung acquisition scan. Right-lung 18fluorodeoxyglucose uptake was assessed using a Patlak plot and values were converted to glucose utilisation. Three clinically inactive pulmonary sarcoidosis patients served as controls. From the 10 CF patients with baseline sputum neutrophils of 14×106 cells·mL−1 who were investigated, seven were found to have sputum at a normal or slightly depressed glucose utilisation rate (mean 1.33 µmol·g−1·h−1) compared with a mean of 2.82 µmol·g−1·h−1 for the sarcoidosis patients. In eight patients, receiving inhaled tobramycin therapy, no change in lung glucose utilisation or sputum neutrophil counts were found. Despite high-sputum neutrophil levels, lung glucose utilisation was not elevated in patients with cystic fibrosis. This study was funded by the Canadian Cystic Fibrosis Foundation (SPARX 2).