title: Early pulmonary involvement in systemic sclerosis assessed by technetium-99m-DTPA clearance rate.
abstract: Systemic sclerosis (SS) is frequently associated with interstitial lung disease, but clinical symptoms and radiologic abnormalities may occur late in the course of the disease. This study investigated early pulmonary involvement by assessing the clearance rate of inhaled 99mTc-diethylenetriaminepentaacetic acid (DTPA).
  
  
  METHODS
  Sixteen patients with proved SS, no clinical pulmonary symptoms and normal chest radiogram were prospectively studied. The 99mTc-DTPA clearance rate was calculated as the time to half clearance (T1/2) and compared with values obtained in healthy nonsmokers.
  
  
  RESULTS
  Six patients showed abnormally increased clearance (T1/2 < 53 min). Rapid clearance was not correlated to SS disease duration or to abnormal pulmonary function tests. Five of six patients with abnormally increased clearance underwent high-resolution CT, which in all five demonstrated pathologic findings that were suggestive of early interstitial disease.
  
  
  CONCLUSIONS
  These findings indicate that in SS asymptomatic patients may frequently present with abnormal 99mTc-DTPA clearance; 99mTc-DTPA lung scintigraphy may allow early detection of subclinical pulmonary involvement in SS.
authors.affiliation: Department of Nuclear Medicine, S. Orsola-Malpighi Policlinic Hospital, Bologna, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Fanti
authors.forename: A
authors.initials: A
authors.lastname: De Fabritiis
authors.forename: D
authors.initials: D
authors.lastname: Aloisi
authors.forename: M
authors.initials: M
authors.lastname: Dondi
authors.forename: M
authors.initials: M
authors.lastname: Marengo
authors.forename: G
authors.initials: G
authors.lastname: Compagnone
authors.forename: F
authors.initials: F
authors.lastname: Fallani
authors.forename: A
authors.initials: A
authors.lastname: Cavalli
authors.forename: N
authors.initials: N
authors.lastname: Monetti
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D013902:Radiography, Thoracic; D011928:Raynaud Disease / Q000150:complications; D012595:Scleroderma, Systemic / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D012907:Smoking; D013147:Spirometry; D016284:Technetium Tc 99m Pentetate / Q000493:pharmacokinetics*; D014055:Tomography, Emission-Computed
chemical_list: D016284:Technetium Tc 99m Pentetate