{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T17:14:32Z","timestamp":1791566072030,"version":"4.3.4"},"reference-count":5,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2025,3,18]],"date-time":"2025-03-18T00:00:00Z","timestamp":1742256000000},"content-version":"vor","delay-in-days":17,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["J Peripheral Nervous Sys"],"published-print":{"date-parts":[[2025,3]]},"abstract":"<jats:title>ABSTRACT<\/jats:title><jats:sec><jats:title>Background and Aims<\/jats:title><jats:p>Leucine Zipper 4 (LUZP4)\u2010immunoglobulin G (IgG) is a novel antibody implicated in germ cell tumor\u2010related paraneoplastic neurologic syndrome. We report a case of painful, progressive tetraparesis associated with testicular seminoma and LUZP4\u2010IgG seropositivity.<\/jats:p><\/jats:sec><jats:sec><jats:title>Case Report<\/jats:title><jats:p>A 51\u2010year\u2010old male presented with a 5\u2010week history of lower limb predominant progressive weakness. Nerve conduction studies (NCS) and electromyography (EMG) revealed a subacute axonal polyradiculoneuropathy. MRI lumbar spine showed thickening of the cauda equina and enhancement of the lower thoracic spinal cord\/conus. Cerebrospinal fluid (CSF) showed a lymphocytic pleocytosis, three oligoclonal bands, and mildly elevated protein. Initial treatment with intravenous immunoglobulin (IVIG) and prednisone produced temporary improvement. CT targeted retroperitoneal lymph node biopsy revealed a seminoma, which was treated with orchiectomy and chemotherapy. The testicular tissue was consistent with a regressed germ cell tumor. His course was subsequently refractory to IVIG, prednisone, and plasma exchange. LUZP4 antibodies were detected in serum, prompting treatment with cyclophosphamide and prednisone. At the 4\u2010month follow\u2010up, the patient had significant improvement in hand strength and had transitioned from walker to cane.<\/jats:p><\/jats:sec><jats:sec><jats:title>Interpretation<\/jats:title><jats:p>LUZP4\u2010IgG seropositivity and identification of retroperitoneal seminoma confirmed a paraneoplastic neurologic syndrome, which is a CD8+ T\u2010cell\u2010mediated disorder. Aggressive immunotherapy was initiated, resulting in clinical improvement. This case underscores the importance of identifying specific serologic biomarkers that can inform therapeutic decisions and improve outcomes.<\/jats:p><\/jats:sec>","DOI":"10.1111\/jns.70013","type":"journal-article","created":{"date-parts":[[2025,3,18]],"date-time":"2025-03-18T11:06:08Z","timestamp":1742295968000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Paraneoplastic Leucine Zipper 4 <scp>IgG<\/scp> Associated Motor\u2010Predominant Polyradiculoneuropathy"],"prefix":"10.1111","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-0124-7864","authenticated-orcid":false,"given":"Alex","family":"Panrudkevich","sequence":"first","affiliation":[{"name":"Mayo Clinic Alix School of Medicine  Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Duaa","family":"Jabari","sequence":"additional","affiliation":[{"name":"Department of Neurology Cedars Sinai  Los Angeles California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brendan","family":"Putko","sequence":"additional","affiliation":[{"name":"Department of Neurology Mayo Clinic  Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Daley","sequence":"additional","affiliation":[{"name":"Department of Neurology Mayo Clinic  Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard A.","family":"Lewis","sequence":"additional","affiliation":[{"name":"Department of Neurology Cedars Sinai  Los Angeles California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Divyanshu","family":"Dubey","sequence":"additional","affiliation":[{"name":"Department of Neurology Mayo Clinic  Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcus V.","family":"Pinto","sequence":"additional","affiliation":[{"name":"Department of Neurology Mayo Clinic  Rochester Minnesota USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2025,3,18]]},"reference":[{"key":"e_1_2_6_2_1","doi-asserted-by":"publisher","DOI":"10.1212\/NXI.0000000000001014"},{"key":"e_1_2_6_3_1","doi-asserted-by":"publisher","DOI":"10.1002\/ana.26050"},{"key":"e_1_2_6_4_1","doi-asserted-by":"publisher","DOI":"10.1212\/CON.0000000000001449"},{"key":"e_1_2_6_5_1","doi-asserted-by":"publisher","DOI":"10.1093\/nar\/gkv070"},{"key":"e_1_2_6_6_1","doi-asserted-by":"publisher","DOI":"10.1007\/s00415\u2010024\u201012425\u2010x"}],"container-title":["Journal of the Peripheral Nervous System"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/jns.70013","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,29]],"date-time":"2025-03-29T00:58:58Z","timestamp":1743209938000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/jns.70013"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,3]]},"references-count":5,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2025,3]]}},"alternative-id":["10.1111\/jns.70013"],"URL":"https:\/\/doi.org\/10.1111\/jns.70013","archive":["Portico"],"relation":{},"ISSN":["1085-9489","1529-8027"],"issn-type":[{"value":"1085-9489","type":"print"},{"value":"1529-8027","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,3]]},"assertion":[{"value":"2025-02-13","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-03-07","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-03-18","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70013"}}