{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T16:21:28Z","timestamp":1773418888047,"version":"3.50.1"},"reference-count":13,"publisher":"The Endocrine Society","issue":"3","license":[{"start":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T00:00:00Z","timestamp":1773360000000},"content-version":"vor","delay-in-days":18,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,2,23]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Although hemoglobin A1c (HbA1c) is widely used to assess long-term glycemia, its reliability declines in conditions that alter red blood cell turnover or hemoglobin glycation. Pancreatic structural diseases, including pancreatic neuroendocrine tumors (pNETs) and intraductal papillary mucinous neoplasms (IPMNs), may further affect glucose regulation through impaired endocrine function. Systemic inflammation and specific hematologic conditions can also create discordant glycemic markers, complicating diagnosis, and management. We report a 59-year-old woman with autoimmune disease who presented with fatigue and fluctuating glucose levels. Her HbA1c remained within normal limits; however, continuous glucose monitoring (CGM) and an oral glucose tolerance test (OGTT) demonstrated marked hyperglycemia. Imaging revealed pancreatic lesions concerning for a pNET in the setting of known IPMNs. Laboratory evaluation was notable for elevated ferritin and clonal hematopoiesis of indeterminate potential (CHIP). Additional studies, including hemoglobin, albumin, renal and hepatic function, and hemoglobin electrophoresis, were normal, ruling out anemia and hemoglobinopathies. Her glycemic discordance likely reflects impaired insulin secretion due to pancreatic pathology combined with inflammation driven alterations in erythrocyte lifespan associated with CHIP. This case underscores the limitations of HbA1c in complex metabolic or inflammatory states and highlights the value of CGM and OGTT when A1c does not align with clinical findings.<\/jats:p>","DOI":"10.1210\/jcemcr\/luag037","type":"journal-article","created":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T12:42:00Z","timestamp":1770468120000},"source":"Crossref","is-referenced-by-count":0,"title":["Normal glycosylated hemoglobin masking glucose dysregulation in a patient with pancreatic and hematologic disease"],"prefix":"10.1210","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-6441-2488","authenticated-orcid":false,"given":"Jean Carlos","family":"Ramos Cardona","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, HCA Florida Orange Park Hospital , Orange Park, FL 32073 ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacqueline","family":"Rodriguez Gilmore","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, HCA Florida Orange Park Hospital , Orange Park, FL 32073 ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tathana","family":"Rivera Hernandez","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, HCA Florida Orange Park Hospital , Orange Park, FL 32073 ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Suzanne","family":"Quinn Martinez","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, HCA Florida Orange Park Hospital , Orange Park, FL 32073 ,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"80","published-online":{"date-parts":[[2026,3,13]]},"reference":[{"key":"2026031309545201000_luag037-B1","author":"American Diabetes Association"},{"issue":"10","key":"2026031309545201000_luag037-B2","doi-asserted-by":"crossref","first-page":"e151","DOI":"10.2337\/dci23-0036","article-title":"Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes Mellitus","volume":"46","author":"Sacks","year":"2023","journal-title":"Diabetes Care"},{"issue":"4","key":"2026031309545201000_luag037-B3","doi-asserted-by":"crossref","first-page":"528","DOI":"10.4103\/2230-8210.98004","article-title":"Drugs affecting HbA1c levels","volume":"16","author":"Unnikrishnan","year":"2012","journal-title":"Indian J Endocrinol Metab"},{"issue":"11","key":"2026031309545201000_luag037-B4","doi-asserted-by":"crossref","first-page":"2589","DOI":"10.2337\/dci21-0043","article-title":"The management of type 1 diabetes in adults. A consensus report by the American diabetes association (ADA) and the European association for the study of diabetes (EASD)","volume":"44","author":"Holt","year":"2021","journal-title":"Diabetes Care"},{"issue":"11","key":"2026031309545201000_luag037-B5","doi-asserted-by":"crossref","first-page":"1978","DOI":"10.2337\/dc23-0805","article-title":"Clonal hematopoiesis of indeterminate potential (CHIP) and incident type 2 diabetes risk","volume":"46","author":"Tobias","year":"2023","journal-title":"Diabetes Care"},{"key":"2026031309545201000_luag037-B6","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/j.yjmcc.2021.07.004","article-title":"Clonal hematopoiesis of indeterminate potential (CHIP): linking somatic mutations, hematopoiesis, chronic inflammation and cardiovascular disease","volume":"161","author":"Marnell","year":"2021","journal-title":"J Mol Cell Cardiol"},{"issue":"2","key":"2026031309545201000_luag037-B7","doi-asserted-by":"crossref","first-page":"267","DOI":"10.2337\/dc23-1276","article-title":"Assessment of glycemic control by continuous glucose monitoring, hemoglobin A1c, fructosamine, and glycated albumin in patients with end-stage kidney disease and burnt-out diabetes","volume":"47","author":"Kaminski","year":"2024","journal-title":"Diabetes Care"},{"issue":"2","key":"2026031309545201000_luag037-B8","doi-asserted-by":"crossref","first-page":"191","DOI":"10.3390\/gastroent14020015","article-title":"Glycemic abnormalities in pancreatic cystic lesions\u2014a single-center retrospective analysis","volume":"14","author":"Balaban","year":"2023","journal-title":"Gastroenterol Insights"},{"issue":"3","key":"2026031309545201000_luag037-B9","doi-asserted-by":"crossref","first-page":"226","DOI":"10.1016\/S2468-1253(16)30106-6","article-title":"Type 3c (pancreatogenic) diabetes mellitus secondary to chronic pancreatitis and pancreatic cancer","volume":"1","author":"Hart","year":"2016","journal-title":"Lancet Gastroenterol Hepatol"},{"issue":"6","key":"2026031309545201000_luag037-B10","doi-asserted-by":"crossref","first-page":"751","DOI":"10.1097\/MPA.0000000000001564","article-title":"Diabetes is associated with the metastasis of pancreatic neuroendocrine tumors","volume":"49","author":"Fan","year":"2020","journal-title":"Pancreas"},{"issue":"11","key":"2026031309545201000_luag037-B11","doi-asserted-by":"crossref","first-page":"1103","DOI":"10.3390\/metabo12111103","article-title":"Impact of diabetes Mellitus in patients with pancreatic neuro-endocrine tumors: causes, consequences, and future perspectives","volume":"12","author":"Hernandez-Rienda","year":"2022","journal-title":"Metabolites"},{"key":"2026031309545201000_luag037-B12","doi-asserted-by":"crossref","first-page":"1181879","DOI":"10.3389\/fpubh.2023.1181879","article-title":"Clonal hematopoiesis as a novel risk factor for type 2 diabetes mellitus in patients with hypercholesterolemia","volume":"11","author":"Kim","year":"2023","journal-title":"Front Public Health"},{"issue":"12","key":"2026031309545201000_luag037-B13","doi-asserted-by":"crossref","first-page":"1148","DOI":"10.1056\/NEJMra1804281","article-title":"Anemia of inflammation","volume":"381","author":"Ganz","year":"2019","journal-title":"N Engl J Med"}],"container-title":["JCEM Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/jcemcr\/article-pdf\/4\/3\/luag037\/67339505\/luag037.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/jcemcr\/article-pdf\/4\/3\/luag037\/67339505\/luag037.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T13:54:58Z","timestamp":1773410098000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/jcemcr\/article\/doi\/10.1210\/jcemcr\/luag037\/8519270"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,2,23]]},"references-count":13,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2026,2,23]]}},"URL":"https:\/\/doi.org\/10.1210\/jcemcr\/luag037","relation":{},"ISSN":["2755-1520"],"issn-type":[{"value":"2755-1520","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2026,3]]},"published":{"date-parts":[[2026,2,23]]},"article-number":"luag037"}}