Ying Du

Objective: This study aimed to investigate the clinical features, differential treatment responses, and management strategies of encephalitis associated with anti-Kelch-like protein 11 (KLHL11) antibodies. Methods: We report two cases of anti-KLHL11 encephalitis that improved following immunotherapy and present a literature review of cases published in the last six years. Results: Case 1 involved a 52-year-old woman who tested positive for serum anti-KLHL11 antibodies at a 1:100 titer. The patient completely recovered following a treatment regimen comprising intravenous immunoglobulin administration at 400 mg/kg/day for 5 days, combined with low-dose rituximab (100 mg, weekly for three consecutive weeks). Extensive tumor screening revealed no underlying malignancies. In Case 2, a 65-year-old man tested positive for anti-KLHL11 antibodies in both serum (titer 1:320) and cerebrospinal fluid (titer 1:100). Initial high-dose intravenous glucocorticoid pulse therapy, starting at 1000 mg dose and tapered by halving the dose every 3 days until discontinuation, combined with low-dose rituximab (100 mg weekly for 3 consecutive weeks), resulted in a suboptimal response, with symptoms recurring after one month. Subsequent administration of efgartigimod (10 mg/kg) led to marked clinical improvement. A testicular ultrasound revealed an epididymal calcification, potentially indicating a burnt-out germ cell tumor. Conclusion: Anti-KLHL11 encephalitis exhibits considerable clinical heterogeneity. A high serum anti-KLHL11 titer (1:320) was associated with treatment refractoriness, this association is a preliminary observation that requires validation in larger cohorts. Efgartigimod appears to be a promising therapeutic option for paraneoplastic neurological syndrome.

Antibody-negative Autoimmune encephalitis (AE) presents a diagnostic challenge, requiring a high index of clinical suspicion and comprehensive evaluation. We report a 66-year-old man presenting with a seizure accompanied by progressive cognitive decline over several days. Despite the presence of hallmark symptoms and suggestive imaging, the patient was initially misdiagnosed, delaying timely immunotherapy. The diagnosis of antibody-negative AE was made based on clinical criteria, including consistent serological and cerebrospinal fluid (CSF) analyses (negative for known autoimmune and paraneoplastic antibodies), alongside a positive tissue-based assay (TBA), cranial MRI findings, and peripheral blood B-cell profiling. The patient responded well to immunotherapy with a low-dose sequential rituximab regimen, demonstrating clinical improvement and halting disease progression. This case highlights the importance of adhering to diagnostic criteria for AE and integrating TBA into the diagnostic workflow for antibody-negative AE.

Combined central and peripheral demyelination (CCPD) is an extremely rare disease characterized by inflammatory demyelination in both the central and peripheral nervous systems. Herein, we reported case of a 14-year-old teenager who initially presented with the symptoms of acute myelitis (AM). Subsequently, the patient developed symptoms consistent with Guillain-Barré syndrome (GBS), which was supported by nerve conduction studies (NCV) and cerebrospinal fluid (CSF) analysis. Throughout the course of the disease, the patient experienced abdominal pain and abnormal liver function. After a comprehensive evaluation, we determined that the abnormal liver function was a result of hepatitis E virus (HEV) infection, which may have acted as a trigger for GBS. The patient was treated with corticosteroids, intravenous immunoglobulin and Rituximab, resulting in symptom relief and clinical improvement after therapy and follow-up. This case highlights the potential responsiveness and reversibility of CCPD. Given the heterogeneous nature of CCPD, there is currently no standardized diagnostic criteria or clear consensus on its treatment. Therefore, we recommend a thorough assessment of all possibilities and the development of consolidated management guidelines based on available data for this disorder.

Immunoglobulin G antibodies to myelin oligodendrocyte glycoprotein (MOG-IgG) associated disease is a rare, demyelinated disease in the central nerve system (CNS) predominately involving optic nerve, spinal cord, and brain leading to optic neuritis (ON), transverse myelitis (TM), encephalitis. The phenotype of MOG-IgG-associated encephalitis is similar to acute disseminated encephalomyelitis (ADEM) presenting with seizures, abnormal behavioral and psychological symptoms, and cognitive impairment. A few brain biopsies show multiple sclerosis (MS) pattern histopathology with T cells, macrophages, and complement activation. To date, how MOG-IgG is produced is unknown. Herein, we report a case of a 32-year-old male with MOG-IgG-associated encephalitis presenting MOG-IgG in cerebrospinal fluid (CSF) but seronegative, as well as Epstein-Barr virus (EBV) infection and Alzheimer's pathologic change in CSF (Aβ42 = 317 pg/ml, T-Tau = 538 pg/ml, p-Tau =10.09 pg/ml). With a combination treatment of administering intravenous immunoglobulin (0.4 mg/kg/d, 5 days) with a low dose of methylprednisolone (80 mg/d, 5 days) and rituximab (100 mg/week, 3 weeks), the patient recovered significantly after 3 months follow-up. This case provides us with new thoughts into the production of MOG-IgG and the possible pathologic mechanism of MOG-IgG-associated disease (MOG-AD) and simultaneously further confirms the interaction between EBV and changes of CSF biomarkers of Alzheimer's disease (AD).

Background: Autoimmune encephalitis (AE) with neuronal surface antibodies (NSAbs) presents pathogenesis mediated by B cell-secreting antibodies. Rituximab is a second-line choice for the treatment for AE with NSAbs, which can cause B cell depletion via targeting CD20. However, the optimal protocol and dosage of rituximab combined with first-line therapy for NSAbs-associated AE remains unclear so far. In this study, we explored the efficacy and safety of low-dose rituximab combined with first-line treatment for NSAbs-associated AE. Methods: Fifty-nine AE patients with NSAbs were enrolled, and retrospectively divided into common first-line therapy (41 patients) and combined low-dose rituximab (100 mg induction weekly with 3 circles, followed by 100 mg reinfusion every 6 months) with first-line therapy (18 patients). Outcome measures included changes in the Clinical Assessment Scale for Autoimmune Encephalitis (CASE) score (primary endpoint), changes in the modified Rankin Scale (mRS), the Mini-mental State Examination (MMSE), the patient and caregiver Neuropsychiatric Inventory (NPI) score at each visit (baseline, discharge, 6 months, 12 months and last follow-up) between two groups (secondary endpoint), as well as oral prednisone dosage, relapse and adverse effects during follow-up. Results: Compared with traditional first-line therapy group, for primary outcome, CASE scores at last follow-up were significantly improved in combined rituximab group, as well as markedly improving changes of CASE scores between baseline and each visit. While changes of mRS, MMSE and NPI scores, as secondary endpoint, were all markedly accelerating improvement between baseline and each visit, as well as both oral prednisone dosage and relapse were also greatly reduced during follow-up. Meanwhile, longitudinal analysis in combination of rituximab cohort also revealed persistently marked amelioration in a series of scales from baseline even more than 1 year. Moreover, analysis in rituximab subgroup showed no difference in any clinical outcomes between combination with single first-line and with repeated first-line treatment (≥ 2 times), while compared to delayed combination with rituximab (> 3 months), early initiation of combination (≤ 3 months) might achieve better improvements in CASE and MMSE assessment even 1 year later. No rituximab-correlated serious adverse events have been reported in our patients. Conclusions: Our simplified regimen of combined low-dose rituximab firstly showed significantly accelerating short-term recovery and long-term improvement for AE with NSAbs, in parallel with markedly reduced prednisone dosage and clinical relapses. Moreover, opportunity of protocol showed earlier initiation (≤ 3 months) with better long-term improvement.

Background Generalized AChR-MG is an archetype of B cell-mediated autoimmune disorders, and use of biologic agent rituximab (RTX) for B cell depletion is generally limited to immunosuppressive therapy-refractory cases. However, benefit of RTX monotherapy and individualized regimen with optimal dosage in early stage of new-onset generalized AChR-MG still remains to be elucidated. In this retrospective study, we explore the efficacy and safety of personalized regimen of 100 mg low-dose rituximab monotherapy in treating new-onset generalized AChR-MG. Methods Thirteen new-onset generalized AChR-MG patients were enrolled for the study, initiating RTX treatment from November 2017 to August 2020. The individualized low-dose RTX monotherapy protocol consisted of 100 mg induction treatment weekly with no more than three circles, followed by reinfusion (100 mg once) sequentially according to whether achieving primary endpoint and peripheral CD19 + B-cell repopulation ≥ 1% of total lymphocytes at each visit (every 3 months). Outcome measures included MGFA-PIS Minimal Manifestation (MM) or better status (primary endpoint), changes in QMG, MMT, MG-ADL and MGQOL-15 scores (secondary endpoint), as well as cholinesterase inhibitors dosage. Results All 13 patients achieved the primary endpoint in parallel with significant improvement of QMG, MMT, MG-ADL MGQOL-15 scores, and reduction of cholinesterase inhibitors dose. A total of 52 visits were performed during follow-up, and only 10 assessments presenting peripheral CD19 + B-cell repopulation (≥ 1%) without “MM or better status” were followed by RTX reinfusions (100 mg once) for clinical remission. The total dosage of RTX was only 346.15 ± 96.74 mg (including 269.23 ± 63.04 mg for induction and 76.92 ± 59.91 mg for reinfusion), which seemed to be much lower than those dosages used in new-onset generalized AChR-MG as described previously. Moreover, compared with patients without thymoma, thymectomy markedly delayed initiation of RTX for patients with thymoma (log-rank test, p = 0.0002), but the delaying treatments showed no influence on the time for achieving primary outcome (log-rank test, p = 0.2517). Conclusion Our study firstly showed that individualized regimen of low-dose RTX monotherapy is effective and safe for early treatment of new-onset generalized AChR-MG, and practicable for directing RTX reinfusion and withdrawal. Moreover, the monotherapy protocol was also indicated to be extensively applicable in both new-onset AChR-MG with thymoma (thymectomy) and without thymoma.

Neuro Behçet's disease (NBD) is a rare but most aggressive manifestation of Behçet's disease (BD) with a poor prognosis, and some patients even present a relapsing and treatment-resistant progressive course. In some relapsing NBD cases, traditional corticosteroids and immunosuppressive drugs show limited efficacy, while benefits of biological agents, such as anti-B-lymphocyte CD20 biological agent rituximab (RTX), gradually represent potential therapeutic advantages with clinical rapid remission and long-time maintenance. However, up to now, the optimal dosage of RTX in NBD is still elucidated. Here, we report two patients with relapsing NBD, despite continuous high dose steroids and sufficient azathioprine treatment, still presenting severe and relapsing meningoencephalitis or brainstem involvement. Repeated low-dose RTX (100 mg × 3/1 week apart, 100 mg repeated every 6 months) is then attempted with rapid recovery and sustained remission. The approach in our cases may expand therapeutic options and provide helpful references for relapsing NBD treatment.

Background: SPG11 mutation-related autosomal recessive hereditary spastic paraplegia with thin corpus callosum (HSP-TCC) is the most common cause in complicated forms of HSP, usually presenting comprehensive mental retardation on early-onset stage preceding spastic paraplegias in childhood. However, there are many instances of sporadic late-onset HSP-TCC cases with a negative family history, and potential mild cognitive deficits in multiple domains may be easily neglected and inaccurately described. Methods: In this study, we performed next generation sequencing in four sporadic late-onset patients with HSP-TCC, and combined Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) to evaluate cognition of the patients. Results: By evolutionary conservation and structural modeling analysis, we have revealed 4 novel pathogenic SPG11 mutations, and firstly confirmed mild cognitive impairment (MCI) with normal MMSE scores (≥27) and decreased MoCA scores (< 26) in these SPG11 mutation-related HSP-TCC patients, predominantly presenting impairment of executive function, delayed recall, abstraction and language. Conclusions: The results expand the mutational spectrum of SPG11-associated HSP-TCC from sporadic cases, and confirm MCI with combination of decreased MoCA and normal MMSE assessment, suggesting that clinicians should consider doing a MoCA to detect MCI in patients with HSP, particularly those with HSP-TCC.