{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T08:26:23Z","timestamp":1759134383195,"version":"3.40.5"},"reference-count":26,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2024,12,19]],"date-time":"2024-12-19T00:00:00Z","timestamp":1734566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"funder":[{"name":"General University Hospital Foundation","award":["PRV00424\/PI_PREMIOS FIHGUV 20\/424"],"award-info":[{"award-number":["PRV00424\/PI_PREMIOS FIHGUV 20\/424"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,5,9]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>The kappa-free light chain (\u03baFLC) index has shown its value in detecting the intrathecal synthesis of immunoglobulins. We aimed to evaluate the diagnostic performance of the \u03baFLC index for multiple sclerosis (MS) and compare different algorithms proposed in the literature to optimize its use for our population.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Based on the results of the oligoclonal bands (OCBs) and \u03baFLC index of 255 patients with suspected MS different optimization strategies were evaluated, for which the optimal \u03baFLC index cut-off thresholds were calculated.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>The best diagnostic performance was achieved by using a reflexive algorithm, in which OCBs are only performed according to the \u03baFLC index result. With a single cut-off (\u03baFLC index = 7.9), an accuracy of 92.2% was obtained (sensitivity = 92.4%, specificity = 92%) with an OCB performance rate of 58.1%. When applying 2 cut-offs (\u03baFLC index = 4.2 and 13), the accuracy was the same (92.2%, sensitivity = 89.6%, specificity = 94%), but the OCB performance rate dropped to 29.4%.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusion<\/jats:title>\n                  <jats:p>The 2-step strategy proposed with \u03baFLC determination followed by OCB analysis in the borderline cases appears to be the most suitable solution, further optimized by adjusting the decision thresholds to 4.2 &amp;lt; \u03baFLC index &amp;lt; 13, resulting in high accuracy and the most saving of OCBs.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/labmed\/lmae101","type":"journal-article","created":{"date-parts":[[2024,12,20]],"date-time":"2024-12-20T08:38:21Z","timestamp":1734683901000},"page":"291-296","source":"Crossref","is-referenced-by-count":2,"title":["Diagnostic approach for multiple sclerosis: optimizing algorithms for intrathecal synthesis of immunoglobulins"],"prefix":"10.1093","volume":"56","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7456-1551","authenticated-orcid":false,"given":"Jorge","family":"Ferriz","sequence":"first","affiliation":[{"name":"Department of Clinical Biochemistry, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristina","family":"Guallart","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pilar","family":"Timoneda","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Fandos","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Javier","family":"Lopez-Arqueros","sequence":"additional","affiliation":[{"name":"Department of Neurology, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Sierra-Rivera","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marta","family":"Garcia-Hita","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Hospital La Vega Lorenzo Guirao , Cieza ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Goitzane","family":"Marcaida","sequence":"additional","affiliation":[{"name":"Department of Clinical Biochemistry, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria","family":"Carcel\u00e9n-Gadea","sequence":"additional","affiliation":[{"name":"Department of Neurology, General University Hospital Consortium of Valencia , Valencia ,","place":["Spain"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2024,12,19]]},"reference":[{"issue":"14","key":"2025051000264652800_CIT0001","doi-asserted-by":"publisher","first-page":"1816","DOI":"10.1177\/1352458520970841","article-title":"Rising prevalence of multiple sclerosis worldwide: insights from the Atlas of MS, third edition","volume":"26","author":"Walton","year":"2020","journal-title":"Mult 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