Journal of Internal Medicine Concepts & Practice >

2025 , Vol. 20 >Issue 05: 381 - 384

DOI: https://doi.org/10.16138/j.1673-6087.2025.05.06

Anti-dipeptidyl-peptidase-like protein 6 encephalitis with symptom improvement without immunotherapy：a case report

  • LI Xueying ,
  • LIU Xiaohong ,
  • ZHAO Wei
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  • Department of Neurology, Putuo People’s Hospital Affiliated to Tongji University, Shanghai 200060, China

Received date: 2025-07-21

  Accepted date: 2025-12-05

  Online published: 2025-12-26

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, 2025, Copyright reserved © 2025.
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Abstract

Anti-dipeptidyl-peptidase-like protein 6 (DPPX) antibody-associated encephalitis is a rare autoimmune encephalitis. This case report describes an elderly male patient with acute onset, whose main symptoms included slurred speech, limb numbness, dizziness, and unsteady gait. The patient had a clear history of preceding infection. Anti-DPPX antibodies were positive in both serum and cerebrospinal fluid, with concurrent seropositivity for anti-ganglioside GQ1b (GQ1b) antibodies. Brain magnetic resonance imaging showed no evidence of acute cerebrovascular disease, tumors, or related lesions. Screening of other systemic organs and lymph nodes revealed no associated malignancies. Without immunotherapy, the patient’s symptoms gradually improved. This case enriches the clinical, diagnostic, and prognostic data on anti-DPPX antibody-associated encephalitis.

Key words： Encephalitis; Anti-dipeptidyl-peptidase-like protein 6 antibody; Clinical features

Cite this article

LI Xueying , LIU Xiaohong , ZHAO Wei . Anti-dipeptidyl-peptidase-like protein 6 encephalitis with symptom improvement without immunotherapy：a case report[J]. Journal of Internal Medicine Concepts & Practice, 2025 , 20(05) : 381 -384 . DOI: 10.16138/j.1673-6087.2025.05.06

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