{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:30:14Z","timestamp":1760059814205,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,13]],"date-time":"2025-07-13T00:00:00Z","timestamp":1752364800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Agency for Medical Research and Development (AMED)","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]},{"name":"Moderna, Inc.","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]},{"name":"JSPS KAKENHI","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]},{"name":"Medical and Biological Laboratories Co., Ltd.","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]},{"name":"Shenzhen YHLO Biotech Co., Ltd.","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]},{"name":"Kowa Co.","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]},{"name":"Research Center for Advanced Science and Technology at the University of Tokyo","award":["JP21nf0101638","23H00503"],"award-info":[{"award-number":["JP21nf0101638","23H00503"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Hemodialysis patients, due to impaired kidney function and compromised immune responses, face increased risks from SARS-CoV-2. Anti-nucleocapsid IgG (anti-IgG N) antibodies are a commonly used marker to assess prior infection in the general population; however, their efficacy for hemodialysis patients remains unclear. Methods: A retrospective study of 361 hemodialysis patients evaluated anti-IgG N antibodies for detecting prior SARS-CoV-2 infection. Antibody levels were measured using a chemiluminescence immunoassay (CLIA) over the four time points. Boxplots illustrated antibody distribution across sampling stages and infection status. Logistic regression and receiver operating characteristic (ROC) curve analysis determined diagnostic accuracy, sensitivity, specificity, and optimal cutoff values. Results: Among the 361 hemodialysis patients, 36 (10.0%) had SARS-CoV-2 infection. Sex distribution showed a trend toward significance (p = 0.05). Boxplot analysis showed that anti-IgG N levels remained low in non-infected patients but increased in infected patients, peaking at the third sampling. Anti-IgG N demonstrated high diagnostic accuracy (AUC: 0.973\u20130.865) but declined over time (p = 0.00525). The optimal cutoff at C1 was 0.01 AU\/mL (sensitivity 1.00, specificity 0.94). Adjusted models had lower predictive value. Conclusions: Anti-IgG N antibodies showed high diagnostic accuracy for detecting prior SARS-CoV-2 infection in hemodialysis patients, though performance declined over time. These findings highlight the need for tailored diagnostic strategies in this vulnerable population.<\/jats:p>","DOI":"10.3390\/vaccines13070750","type":"journal-article","created":{"date-parts":[[2025,7,15]],"date-time":"2025-07-15T11:52:58Z","timestamp":1752580378000},"page":"750","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Anti-Nucleocapsid IgG Antibody as a Marker of SARS-CoV-2 Infection for Hemodialysis Patients"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-5175-6153","authenticated-orcid":false,"given":"Akemi","family":"Hara","sequence":"first","affiliation":[{"name":"Clinical Research Center, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shun","family":"Watanabe","sequence":"additional","affiliation":[{"name":"Department of Urology, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1482-6618","authenticated-orcid":false,"given":"Toyoaki","family":"Sawano","sequence":"additional","affiliation":[{"name":"Department of Surgery, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"},{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuki","family":"Sonoda","sequence":"additional","affiliation":[{"name":"Department of Nursing, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0824-454X","authenticated-orcid":false,"given":"Hiroaki","family":"Saito","sequence":"additional","affiliation":[{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"},{"name":"Department of Internal Medicine, Soma Central Hospital, Soma 976-0016, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4415-9657","authenticated-orcid":false,"given":"Akihiko","family":"Ozaki","sequence":"additional","affiliation":[{"name":"Clinical Research Center, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"},{"name":"Breast and Thyroid Center, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3953-0872","authenticated-orcid":false,"given":"Masatoshi","family":"Wakui","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Keio University School of Medicine, Shinju-ku 160-8582, Tokyo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8602-6786","authenticated-orcid":false,"given":"Tianchen","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chika","family":"Yamamoto","sequence":"additional","affiliation":[{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yurie","family":"Kobashi","sequence":"additional","affiliation":[{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"},{"name":"Department of Internal Medicine, Seireikai Group Hirata Central Hospital, Hirata, Ishikawa-gun 963-8202, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-2496-8456","authenticated-orcid":false,"given":"Toshiki","family":"Abe","sequence":"additional","affiliation":[{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takeshi","family":"Kawamura","sequence":"additional","affiliation":[{"name":"Isotope Science Center, The University of Tokyo, Bunkyo-ku 113-0032, Tokyo, Japan"},{"name":"Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku 153-8904, Tokyo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akira","family":"Sugiyama","sequence":"additional","affiliation":[{"name":"Isotope Science Center, The University of Tokyo, Bunkyo-ku 113-0032, Tokyo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aya","family":"Nakayama","sequence":"additional","affiliation":[{"name":"Isotope Science Center, The University of Tokyo, Bunkyo-ku 113-0032, Tokyo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yudai","family":"Kaneko","sequence":"additional","affiliation":[{"name":"Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku 153-8904, Tokyo, Japan"},{"name":"Medical and Biological Laboratories Co., Ltd., Minato-ku 105-0012, Tokyo, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3064-0127","authenticated-orcid":false,"given":"Hiroaki","family":"Shimmura","sequence":"additional","affiliation":[{"name":"Department of Urology, Jyoban Hospital of Tokiwa Foundation, Iwaki 972-8322, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8027-202X","authenticated-orcid":false,"given":"Masaharu","family":"Tsubokura","sequence":"additional","affiliation":[{"name":"Department of Radiation Health Management, Fukushima Medical University School of Medicine, Fukushima City 960-1295, Fukushima, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1540","DOI":"10.1016\/j.kint.2020.09.006","article-title":"Results from the ERA-EDTA Registry indicate a high mortality due to COVID-19 in dialysis patients and kidney transplant recipients across Europe","volume":"98","author":"Jager","year":"2020","journal-title":"Kidney Int."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"748","DOI":"10.1053\/j.ajkd.2021.01.003","article-title":"COVID-19 among US dialysis patients: Risk factors 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