title: Case report: extreme CgA elevation under PPI confounding assessment of adrenal mass.
abstract: Measurement of chromogranin A (CgA) level in blood can be used to monitor neuroendocrine tumours. However CgA level may also be elevated in several other endocrine and non-endocrine diseases. Here, we report on a patient with an incidental left-sided adrenal tumour and elevated CgA level. Adrenalectomy did not confirm clinically suspected diagnosis of pheochromocytoma. Postoperative follow-up was remarkable for a persistently elevated CgA level suspecting another neuroendocrine tumour which could not be detected despite extensive investigations. Finally, it was discovered that continuous proton-pump inhibitor administration for gastro-oesophageal reflux disease had caused a falsely elevated CgA level.
authors.affiliation: Abteilung Innere I, St.-Marien-Krankenhaus Berlin, Gallwitzallee 123 - 143, 12249 Berlin, Germany. wiedmann@marienkrankenhaus-berlin.de
authors.forename: M W
authors.initials: MW
authors.lastname: Wiedmann
authors.forename: J
authors.initials: J
authors.lastname: Mössner
authors.forename: M
authors.initials: M
authors.lastname: Stumvoll
authors.forename: D
authors.identifier: 0000-0003-0357-4192
authors.initials: D
authors.lastname: Führer
mesh_terms: D000311:Adrenal Glands / Q000187:drug effects* / Q000378:metabolism*; D053379:Chromogranin A / Q000097:blood*; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate / Q000187:drug effects; D008875:Middle Aged; D054328:Proton Pump Inhibitors / Q000008:administration & dosage*
chemical_list: D053379:Chromogranin A; D054328:Proton Pump Inhibitors