{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T14:50:35Z","timestamp":1791989435961,"version":"4.4.0"},"reference-count":16,"publisher":"Wiley","issue":"19","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Clinical Laboratory Analysis"],"published-print":{"date-parts":[[2026,10]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Pseudohypercalcemia is easily misdiagnosed in clinical practice, potentially leading to unnecessary interventions. Multiple myeloma (MM) presenting with concurrent hypergammaglobulinemia represents a rare etiology of pseudohypercalcemia, and there are few reports of systematic laboratory validation of this pathological entity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We report a patient with MM who presented with markedly elevated serum total calcium on routine biochemical testing. The hypercalcemia persisted despite 1\u2009month of calcitonin therapy administered at an external hospital. After admission, the clinical laboratory team performed a panel of confirmatory assays, including direct ionized calcium measurement, post\u2010dilution linearity evaluation, inductively coupled plasma mass spectrometry (ICP\u2010MS) verification, and polyethylene glycol (PEG) precipitation testing.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results and Conclusions<\/jats:title>\n                    <jats:p>The results confirmed that the elevation in serum total calcium was attributed to enhanced calcium binding to circulating globulins, secondary to hypergammaglobulinemia, rather than analytical interference in the detection system. During clinical follow\u2010up, serum total calcium levels normalized progressively in parallel with the decline in globulin levels following targeted anti\u2010myeloma therapy. This case demonstrates that clinicians and laboratory professionals should maintain a high index of suspicion for pseudohypercalcemia when encountering patients with marked paraproteinemia or abnormal circulating macromolecules. A multimodal differential diagnostic approach using complementary laboratory indicators is warranted to avoid unnecessary examinations and interventions, thereby reducing the waste of medical resources and preventing potential adverse events associated with inappropriate treatment.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/jcla.70342","type":"journal-article","created":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T05:41:26Z","timestamp":1788327686000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Laboratory Identification of Pseudohypercalcemia Induced by Hyperglobulinemia in Multiple Myeloma: A Case Report"],"prefix":"10.1002","volume":"40","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-6628-3326","authenticated-orcid":false,"given":"Anjiang","family":"Zhao","sequence":"first","affiliation":[{"name":"Department of Laboratory Medicine West China Hospital, Sichuan University  Chengdu Sichuan Province China"},{"name":"Sichuan Clinical Research Center for Laboratory Medicine  Chengdu Sichuan Province China"},{"name":"Clinical Laboratory Medicine Research Center of West China Hospital  Chengdu Sichuan Province China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4559-3186","authenticated-orcid":false,"given":"Fan","family":"Zhong","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine West China Hospital, Sichuan University  Chengdu Sichuan Province China"},{"name":"Department of Laboratory Medicine Xindu District People's Hospital  Chengdu Sichuan Province China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yankui","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine West China Hospital, Sichuan University  Chengdu Sichuan Province China"},{"name":"Department of Clinical Laboratory Guidong People's Hospital of Guangxi Zhuang Autonomous Region  Wuzhou Guangxi Zhuang Autonomous Region China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0107-213X","authenticated-orcid":false,"given":"Guixing","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine West China Hospital, Sichuan University  Chengdu Sichuan Province China"},{"name":"Sichuan Clinical Research Center for Laboratory Medicine  Chengdu Sichuan Province China"},{"name":"Clinical Laboratory Medicine Research Center of West China Hospital  Chengdu Sichuan Province China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,1]]},"reference":[{"key":"e_1_2_12_2_1","first-page":"1","article-title":"Diagnosis and Management of Multiple Myeloma With Central Nervous System Involvement","volume":"24","author":"D'Angelo C. R.","year":"2026","journal-title":"Journal of the National Comprehensive Cancer Network: JNCCN"},{"key":"e_1_2_12_3_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12882-025-04397-5"},{"key":"e_1_2_12_4_1","doi-asserted-by":"publisher","DOI":"10.1093\/ejendo\/lvaf151"},{"key":"e_1_2_12_5_1","doi-asserted-by":"publisher","DOI":"10.3389\/fonc.2024.1441851"},{"key":"e_1_2_12_6_1","first-page":"246","article-title":"Pseudohypercalcemia in Multiple Myeloma: A Case Report","volume":"11","author":"Ashrafi F.","year":"2017","journal-title":"International Journal of Hematology\u2010Oncology and Stem Cell Research"},{"key":"e_1_2_12_7_1","doi-asserted-by":"publisher","DOI":"10.3322\/caac.21489"},{"key":"e_1_2_12_8_1","doi-asserted-by":"publisher","DOI":"10.1177\/000456329703400618"},{"key":"e_1_2_12_9_1","first-page":"244","article-title":"Multiple Myeloma: Diagnosis and Treatment","volume":"113","author":"Hughes P. M. F.","year":"2026","journal-title":"American Family Physician"},{"key":"e_1_2_12_10_1","first-page":"E46","article-title":"A Rare Case of Pseudohypercalcemia Associated With Multiple Myeloma","volume":"71","author":"Mishima C.","year":"2025","journal-title":"Kobe Journal of Medical Sciences"},{"key":"e_1_2_12_11_1","doi-asserted-by":"publisher","DOI":"10.4158\/EP.1.6.390"},{"key":"e_1_2_12_12_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00914965"},{"key":"e_1_2_12_13_1","doi-asserted-by":"publisher","DOI":"10.1111\/imj.12210"},{"key":"e_1_2_12_14_1","doi-asserted-by":"publisher","DOI":"10.1155\/2024\/8844335"},{"key":"e_1_2_12_15_1","doi-asserted-by":"publisher","DOI":"10.1111\/cen.15179"},{"key":"e_1_2_12_16_1","doi-asserted-by":"publisher","DOI":"10.3389\/fendo.2025.1715348"},{"key":"e_1_2_12_17_1","doi-asserted-by":"publisher","DOI":"10.3390\/jcm14217676"}],"container-title":["Journal of Clinical Laboratory Analysis"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jcla.70342","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/jcla.70342","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jcla.70342","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T14:29:36Z","timestamp":1791988176000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jcla.70342"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,1]]},"references-count":16,"journal-issue":{"issue":"19","published-print":{"date-parts":[[2026,10]]}},"alternative-id":["10.1002\/jcla.70342"],"URL":"https:\/\/doi.org\/10.1002\/jcla.70342","archive":["Portico"],"relation":{},"ISSN":["0887-8013","1098-2825"],"issn-type":[{"value":"0887-8013","type":"print"},{"value":"1098-2825","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,1]]},"assertion":[{"value":"2026-05-13","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-08-17","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-01","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70342"}}