Use of intravenous immunoglobulin for the treatment of autoimmune encephalitis: audit of the NHS experience

BRAF Inhibitor Therapy-Related Encephalitis in a Patient with Metastatic Melanoma

INTRODUCTION

BRAF inhibitors such as encorafenib and vemurafenib in combination with MEK inhibitors are commonly used for the treatment of patients with BRAF V600-mutant melanoma.

CASE PRESENTATION

A patient with relapsed metastatic melanoma with a BRAF V600 mutation was started on treatment with vemurafenib and cobimetinib. Within 2 weeks of treatment start, he was hospitalized and diagnosed with encephalitis through a lumbar puncture and treated with corticosteroids, with subsequent normalization of cerebrospinal fluid (CSF) findings. When he recovered and was switched to encorafenib treatment, the same symptoms recurred, and the patient was treated with high-dose steroids and intravenous immunoglobulin, again with improvement in his CSF. He has not had a relapse of his symptoms since BRAF inhibitor treatment was permanently discontinued.

CONCLUSION

This is the first known report of a patient who has developed encephalitis because of treatment with BRAF inhibitors.

Autoimmune Encephalitis in Tunisia: Report of a Pediatric Cohort

Background

Autoimmune encephalitis (AE) is a rapidly progressive encephalopathy caused by antibodies targeting neurons in the central nervous system generating specific immune responses. It is increasingly recognized in children.

Objective

To describe clinical, neuroimaging, and laboratory features, treatment, and outcome in a cohort of Tunisian children with AE.

Methods

We conducted a retrospective review of the medical records of all children attending the Department of Child and Adolescent Neurology (Tunis) with autoimmune encephalitis between 2004 and 2020. Clinical, neuroimaging, laboratory features, therapeutic data, and outcome were analyzed.

Results

Nineteen children were included in the study (12 girls and 7 boys). The median age at diagnosis was 7.68 years (range: 10 months-13 years). The most frequent manifestations were seizures and behavioral disorders. Eleven cases were diagnosed with anti-NMDA receptor encephalitis, 4 cases with anti-Ma2 encephalitis, 3 cases with anti-GAD encephalitis, and 1 case with anti-SOX1 encephalitis. Brain MRI showed increased T2 and fluid-attenuated inversion recovery (FLAIR) signal of the temporal lobe in 5 patients. Eighteen patients showed improvement following first-line immunotherapy (high-dose corticosteroids, intravenous immunoglobulin). One patient with anti-GAD encephalitis died despite escalating immunotherapy.

Conclusion

Diagnosis of autoimmune encephalitis is challenging in children, because of misleading presentations. An early and accurate diagnosis is important to enable proper therapeutic interventions.

Autoimmune Encephalitis: NMDA Receptor Encephalitis as an Example of Translational Neuroscience

Autoimmune encephalitis (AE) is a group of disorders causing synaptic receptor dysfunction with a broad range of neurological symptoms that has been historically difficult to differentiate clinically. Today, AE represents an excellent example of the rapid determination of the cause of a disease and the ability to identify potential treatments using relatively simple basic science techniques of investigation. Of the number of autoimmune encephalitides identified thus far, one of the best examples of the impact of basic science studies on disease management is NMDA receptor mediated autoimmune encephalitis (NMDAr-AE). In this review, we will provide an overview of the epidemiology of NMDAr-AE, clinical features and treatments, and the basic science tools and techniques that were used to identify the cause, correlate symptoms to underlying pathophysiology, and to understand the mechanism of disease pathology.

A paraneoplastic limbic encephalitis from an anorectal small cell neuroendocrine carcinoma: a case report

BACKGROUND

Paraneoplastic limbic encephalitis (PLE) is a rare autoimmune neurological syndrome observed in cancer patients. PLE is difficult to diagnose and presents a variable response to treatment, depending on the characteristics of the tumor and neuronal autoantibodies.

CASE PRESENTATION

A 64-year-old, Caucasian, non-smoker man presented with a rapidly developing cognitive impairment, personality change, spatial disorientation, and short-term memory loss associated with anorexia and cervical and inguinal lymph nodes. The ¹⁸F-FDG PET scan documented intensely hypermetabolic lymph nodes, which histologically corresponded to a metastasis from a small cell neuroendocrine carcinoma. The brain MRI revealed a high T2-weighted FLAIR signal of the hippocamps, consisted with a PLE. The presence of anti-neuronal Hu antibodies confirmed the diagnosis. The patient underwent plasmapheresis, associated to a systemic chemotherapy resulting in a partial and temporary improvement of the neurological symptoms. Four cycles of intravenous immunoglobulins were also necessary. After six cures of chemotherapy, the lymph node metastases regressed. However, a new anorectal lesion was detected and was histologically confirmed as a primary small cell neuroendocrine carcinoma, which was treated with concomitant chemoradiotherapy. At the end of this treatment, the patient showed a rapid tumor progression leading to his death.

CONCLUSIONS

This case highlights the rare entity, PLE, which is difficult to diagnose and manage. In addition, this is the first published case of PLE associated with an anorectal small cell neuroendocrine carcinoma, which appeared after completion of systemic chemotherapy.