title: [Increased serum activity of angiotensin-converting enzyme (ACE): indication of sarcoidosis? A 'Bayesian' approach].
abstract: Two patients, a man aged 23 and a woman aged 42 years, complained of fatigue and arthralgia respectively. A particularly high serum activity of angiotensin-converting enzyme (ACE) was established during the diagnostic work-up, although sarcoidosis was considered to be unlikely. This led to a series of diagnostic procedures, some invasive, to confirm the diagnosis of sarcoidosis. The diagnosis was not made in either of these patients. The fatigue appeared to be self-limiting and the arthralgia was due to arthrosis. Eventually it was discovered that these patients had a familial elevation of serum ACE activity. The elevation of ACE levels has limited specificity for sarcoidosis (85%) and is therefore of no value in the diagnostic workup, if the a priori probability for sarcoidosis is low.
authors.affiliation: Universitair Medisch Centrum St. Radbound, afd. Algemene Interne Geneeskunde, Postbus 9101, 6500 HB Nijmegen. c.kramers@pharmtox.umcn.nl
authors.forename: C
authors.initials: C
authors.lastname: Kramers
authors.forename: J
authors.initials: J
authors.lastname: Deinum
mesh_terms: D000328:Adult; D018771:Arthralgia / Q000209:etiology; D001499:Bayes Theorem; D015415:Biomarkers / Q000097:blood; D003937:Diagnosis, Differential; D005221:Fatigue / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008661:Metabolism, Inborn Errors / Q000175:diagnosis / Q000201:enzymology*; D007703:Peptidyl-Dipeptidase A / Q000097:blood* / Q000235:genetics / Q000378:metabolism; D012507:Sarcoidosis / Q000175:diagnosis / Q000201:enzymology*; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D007703:Peptidyl-Dipeptidase A