title: ACE levels may affect cystatin C measurements.
abstract: OBJECTIVE
  To assess the relationship between angiotensin-converting enzyme (ACE) levels and cystatin C in a patient with the presumed diagnosis of sarcoidosis.
  
  
  METHODS
  Case report with correlation analysis between ACE levels and cystatin C concentrations while considering gold-standard nuclear medicine glomerular filtration rate (GFR) methods for the measurement of renal function.
  
  
  RESULTS
  We observed a strong correlation between ACE levels and cystatin C concentration in 12-year old with the presumed diagnosis of sarcoidosis in the absence of renal pathology and abnormal renal function.
  
  
  CONCLUSIONS
  Elevated ACE levels may cause non-specific cystatin C elevation irrespective of GFR.
authors.affiliation: Department of Pediatrics, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada; Department of Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada; Department of Pathology and Laboratory Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N5A 5A5, Canada. Electronic address: guido.filler@lhsc.on.ca.
authors.forename: Guido
authors.initials: G
authors.lastname: Filler
authors.affiliation: Department of Pediatrics, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada; Department of Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada.
authors.forename: Roberta A
authors.initials: RA
authors.lastname: Berard
authors.affiliation: Department of Pediatrics, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada; Department of Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, N6A 5W9, Canada.
authors.forename: Shih-Han Susan
authors.initials: SH
authors.lastname: Huang
mesh_terms: D002648:Child; D055316:Cystatin C / Q000097:blood*; D006801:Humans; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*
chemical_list: D055316:Cystatin C; D007703:Peptidyl-Dipeptidase A
keywords: Angiotensin converting enzyme; Cystatin C; Glomerular filtration rate; Sarcoidosis