{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T03:36:14Z","timestamp":1790998574703,"version":"4.1.0"},"reference-count":31,"publisher":"SAGE Publications","issue":"2","license":[{"start":{"date-parts":[[2025,12,27]],"date-time":"2025-12-27T00:00:00Z","timestamp":1766793600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"funder":[{"DOI":"10.13039\/501100003645","name":"National Cancer Center","doi-asserted-by":"publisher","award":["Grant No. 2510580"],"award-info":[{"award-number":["Grant No. 2510580"]}],"id":[{"id":"10.13039\/501100003645","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Mult Scler"],"published-print":{"date-parts":[[2026,2]]},"abstract":"<jats:sec>\n                    <jats:title>Background:<\/jats:title>\n                    <jats:p>The kappa free light chain (KFLC) index is a quantitative marker of intrathecal immunoglobulin synthesis with diagnostic performance comparable to cerebrospinal fluid (CSF)-restricted oligoclonal bands (OCBs). Its utility in Asian populations, where multiple sclerosis (MS) is less prevalent and mimics such as neuromyelitis optica spectrum disorder (NMOSD) and MOG antibody-associated disease (MOGAD) are common, remains underexplored.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives:<\/jats:title>\n                    <jats:p>We aimed to validate the KFLC index and determine optimal thresholds for MS diagnosis in a Korean cohort.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>We retrospectively analyzed 208 patients undergoing CSF evaluation, including 103 with MS and 105 with non-MS conditions (64 NMOSD, 14 MOGAD, 27 others). KFLC-related biomarkers were compared, and receiver operating characteristic analyses identified thresholds.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>\n                      When comparing the MS group (\n                      <jats:italic toggle=\"yes\">n<\/jats:italic>\n                      \u2009=\u2009103) with the non-MS group (\n                      <jats:italic toggle=\"yes\">n<\/jats:italic>\n                      \u2009=\u2009105), the optimal KFLC index threshold was \u2a7e12.6, yielding sensitivity 84%, specificity 74%, and accuracy 79%. Combining KFLC index \u2a7e12.6 with OCB positivity increased specificity to 93%. Sex-specific thresholds (\u2a7e22.8 for females, \u2a7e7.0 for males) improved performance, increasing male sensitivity and female specificity reaching 82%.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion:<\/jats:title>\n                    <jats:p>The KFLC index is a reliable biomarker for MS diagnosis in Asian populations. Optimized and sex-specific thresholds may enhance diagnostic precision where MS mimics are relatively prevalent, consistent with diagnostic performance globally.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/13524585251399102","type":"journal-article","created":{"date-parts":[[2025,12,27]],"date-time":"2025-12-27T10:20:38Z","timestamp":1766830838000},"page":"169-178","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":7,"title":["Optimizing kappa free light chain index thresholds for multiple sclerosis (MS) diagnosis in low-MS prevalence regions: Insights from an Asian cohort"],"prefix":"10.1177","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0679-0918","authenticated-orcid":false,"given":"Su-Hyun","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5189-1323","authenticated-orcid":false,"given":"You-Ri","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea; Department of Neurology, Chonnam National University Hospital, Gwangju, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-3267-2085","authenticated-orcid":false,"given":"Jieun","family":"Chung","sequence":"additional","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-3106-0454","authenticated-orcid":false,"given":"Minji","family":"Joo","sequence":"additional","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7112-5957","authenticated-orcid":false,"given":"Rosah May Palermo","family":"Payumo","sequence":"additional","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6428-061X","authenticated-orcid":false,"given":"Ki Hoon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Neurology, Severance Hospital, College of Medicine, Yonsei University, Seoul, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0288-771X","authenticated-orcid":false,"given":"Jae-Won","family":"Hyun","sequence":"additional","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8672-8419","authenticated-orcid":false,"given":"Ho Jin","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Neurology, Research Institute and Hospital of National Cancer Center, Goyang, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2025,12,27]]},"reference":[{"key":"e_1_3_2_2_2","doi-asserted-by":"publisher","DOI":"10.1177\/1352458515594044"},{"key":"e_1_3_2_3_2","doi-asserted-by":"publisher","DOI":"10.1515\/cclm-2017-0285"},{"key":"e_1_3_2_4_2","doi-asserted-by":"publisher","DOI":"10.1007\/s10354-022-00912-7"},{"key":"e_1_3_2_5_2","doi-asserted-by":"publisher","DOI":"10.1177\/13524585221134213"},{"key":"e_1_3_2_6_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jneuroim.2019.577108"},{"key":"e_1_3_2_7_2","doi-asserted-by":"publisher","DOI":"10.1093\/brain\/awac220"},{"key":"e_1_3_2_8_2","doi-asserted-by":"publisher","DOI":"10.1212\/NXI.0000000000000775"},{"key":"e_1_3_2_9_2","doi-asserted-by":"publisher","DOI":"10.1016\/S1474-4422(25)00270-4"},{"key":"e_1_3_2_10_2","doi-asserted-by":"publisher","DOI":"10.1097\/WCO.0000000000000315"},{"key":"e_1_3_2_11_2","doi-asserted-by":"publisher","DOI":"10.1111\/ene.15897"},{"key":"e_1_3_2_12_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jneuroim.2019.577122"},{"key":"e_1_3_2_13_2","doi-asserted-by":"publisher","DOI":"10.1111\/sji.13421"},{"issue":"4","key":"e_1_3_2_14_2","first-page":"627","article-title":"Kappa free light chains in multiple sclerosis as a marker of intrathecal humoral response: A sex-disaggregated study","volume":"14","author":"Candeloro R","year":"2024","unstructured":"Candeloro R, Galloppa M, Lombardo L, et al. Kappa free light chains in multiple sclerosis as a marker of intrathecal humoral response: A sex-disaggregated study. 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Diagnostic approach for multiple sclerosis: Optimizing algorithms for intrathecal synthesis of immunoglobulins. 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