title: Serial chitotriosidase measurements in sarcoidosis--two to five year follow-up study.
abstract: BACKGROUND
  Chitotriosidase (CTO) is a human chitinolytic enzyme secreted by activated macrophages and polymorphonuclear neutrophils. Albeit not specific for sarcoidosis, it is increased in over 90% of patients with active disease. The aims of this study were to correlate CTO measurements with clinical assessment of sarcoidosis and to test CTO as a marker of sarcoidosis relapse.
  
  
  METHODS
  95 patients were followed-up for 24-60 months. Serial CTO measurements were performed every 3-6 months and correlated to clinical symptoms, lung function (FVC and DLco) and chest X-ray. In 38 patients clinical outcome status (COS) at 5 years was determined.
  
  
  RESULTS
  Initial CTO levels were significantly higher in patients with impaired FVC/DLco (p = 0.011 for both) but there was no correlation with standard chest X-ray stages. Patients with Loefgren's syndrome had significantly lower initial and control CTO level compared to other patients (p = 0.011 and p = 0.001, respectively). At follow-up there was a positive correlation of CTO and deterioration of clinical symptoms (p < 0.001), chest X-ray (p < 0.001) and FVC/DLco (p = 0.012 and p = 0.086, respectively). Control CTO levels were significantly lower in no disease groups versus minimal or persistent disease group as defined by COS (p = 0.003 and p < 0.001, respectively). At relapse CTO increased for 100% or more from baseline value in 12/14 patients.
  
  
  CONCLUSIONS
  It was shown that CTO correlates with certain sarcoidosis phenotypes (Loefgren's syndrome, COS) and that serial measurements of CTO correlate with clinical symptoms, chest radiographs and lung function.
authors.affiliation: Department of Pulmonary Diseases, University Medical Centre Ljubljana, Zaloška 7, 1000 Ljubljana, Slovenia. Electronic address: matevz.harlander@gmail.com.
authors.forename: Matevž
authors.initials: M
authors.lastname: Harlander
authors.affiliation: Department of Pulmonary Diseases, University Medical Centre Ljubljana, Zaloška 7, 1000 Ljubljana, Slovenia.
authors.forename: Barbara
authors.initials: B
authors.lastname: Salobir
authors.affiliation: Laboratory Department, Children's Hospital, University Medical Center Ljubljana, Zaloška 7, 1000 Ljubljana, Slovenia.
authors.forename: Mirjana
authors.initials: M
authors.lastname: Zupančič
authors.affiliation: Institute of Radiology, University Medical Centre Ljubljana, Zaloška 7, 1000 Ljubljana, Slovenia.
authors.forename: Marija
authors.initials: M
authors.lastname: Dolenšek
authors.affiliation: Institute of Radiology, University Medical Centre Ljubljana, Zaloška 7, 1000 Ljubljana, Slovenia.
authors.forename: Tanja
authors.initials: T
authors.lastname: Bavčar Vodovnik
authors.affiliation: Department of Pulmonary Diseases, University Medical Centre Ljubljana, Zaloška 7, 1000 Ljubljana, Slovenia.
authors.forename: Marjeta
authors.initials: M
authors.lastname: Terčelj
mesh_terms: D000328:Adult; D000368:Aged; D000935:Antifungal Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D001800:Blood Specimen Collection / Q000379:methods; D004796:Clinical Enzyme Tests / Q000379:methods; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D005938:Glucocorticoids / Q000627:therapeutic use; D006596:Hexosaminidases / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011653:Pulmonary Diffusing Capacity / Q000502:physiology; D011859:Radiography; D012008:Recurrence; D012507:Sarcoidosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology; D014797:Vital Capacity / Q000502:physiology; D055815:Young Adult
chemical_list: D000935:Antifungal Agents; D015415:Biomarkers; D005938:Glucocorticoids; D006596:Hexosaminidases; C086400:chitotriosidase
keywords: Chitotriosidase; Follow-up; Sarcoidosis