Extreme delta brush and distinctive imaging in a pediatric patient with autoimmune GFAP astrocytopathy

Glial Fibrillary Acidic Protein (GFAP) Astrocytopathy: An Emerging Cause of Meningoencephalomyelitis in Children and Adolescents

Introduction: We describe 5 children with GFAP astrocytopathy with the goal of further characterizing this rare form of meningoencephalomyelitis. Methods: Retrospective chart review of patients diagnosed with GFAP astrocytopathy between 2019 and 2021. Results: Patients were 8-17 years old, and all were male. Fever, headache, and vomiting were common presenting symptoms, and weakness, tremor, and ataxia were common initial examination findings. Initial magnetic resonance imaging (MRI) showed spinal cord abnormalities in 2 patients and leptomeningeal enhancement in 1. Most patients had cerebral spinal fluid pleocytosis, and all screened negative for malignancy. Three patients progressed to coma, and all were treated with immunosuppressant therapy. By discharge, all patients had improved over their clinical nadir, although none had returned to baseline. Discussion: GFAP astrocytopathy is a recently recognized cause of meningoencephalomyelitis in children. Here, we expand our understanding of this entity with the goal of aiding those treating children with GFAP astrocytopathy.

Magnetic Resonance Imaging Characteristics of Autoimmune Glial Fibrillary Acidic Protein (GFAP) Astrocytopathy: A Pediatric Series in Southwest China

Objective

To investigate and summarize the magnetic resonance imaging (MRI) manifestations of autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy in children.

Methods

We retrospectively analyzed data from 17 pediatric patients with autoimmune GFAP astrocytopathy confirmed by the detection of GFAP autoantibodies in cerebrospinal fluid in our single-center. Furthermore, we reviewed current literature and summarized previous findings on the MRI characteristics of this disease in children.

Results

In these 17 patients, the clinical manifestations and results of CSF analysis were suggestive of autoimmune disorder, with a good improvement. The lesions on MRI were most commonly located in the bilateral basal ganglia (70.6%), thalamus (64.7%), cerebral white matter (29.4%). 93.3% of the cerebral lesions were relatively scattered and small, 80% of the spinal lesions presented as longitudinally extensive ones. Both periventricular radial linear (PVRL) (53.8%) and punctate or linear enhancement in basal ganglia and thalamus (53.8%) were commonly observed, followed by the leptomeningeal enhancement (46.2% in the brain and 62.5% in the spinal cord). We then included 55 pediatric patients with MRI data from current literature in our analysis (n = 72, 44 males). Our results revealed similar MRI findings but the enhancement pattern between our series and previously published cases, that is, leptomeningeal enhancement in the brain 46.2% vs 31.4%, in spinal cord 62.5% vs 18.4%, and PVRL enhancement 53.8% vs 11.2%. There were no detailed reports on punctate or linear enhancement.

Conclusion

The MRI characteristics of autoimmune GFAP astrocytopathy in children could be suggestive. Scattered and small lesions (especially punctate or linear) in the bilateral thalamus, basal ganglia, and white matter, as well as longitudinally extensive spinal cord lesions (if present), with punctate, PVRL and leptomeningeal enhancement might be a distinct indication for the early diagnosis of this disorder.

MR Imaging Findings in a Large Population of Autoimmune Encephalitis

BACKGROUND AND PURPOSE

Autoimmune encephalitis is a rare condition in which autoantibodies attack neuronal tissue, causing neuropsychiatric disturbances. This study sought to evaluate MR imaging findings associated with subtypes and categories of autoimmune encephalitis.

MATERIALS AND METHODS

Cases of autoimmune encephalitis with specific autoantibodies were identified from the medical record (2009-2019). Cases were excluded if no MR imaging of the brain was available, antibodies were associated with demyelinating disease, or >1 concurrent antibody was present. Demographics, CSF profile, antibody subtype and group (group 1 intracellular antigen or group 2 extracellular antigen), and MR imaging features at symptom onset were reviewed. Imaging and clinical features were compared across antibody groups using χ² and Wilcoxon rank-sum tests.

RESULTS

Eighty-five cases of autoimmune encephalitis constituting 16 distinct antibodies were reviewed. The most common antibodies were anti-N-methyl-D-aspartate (n = 41), anti-glutamic acid decarboxylase (n = 7), and anti-voltage-gated potassium channel (n = 6). Eighteen of 85 (21%) were group 1; and 67/85 (79%) were group 2. The median time between MR imaging and antibody diagnosis was 14 days (interquartile range, 4-26 days). MR imaging had normal findings in 33/85 (39%), and 20/33 (61%) patients with normal MRIs had anti-N-methyl-D-aspartate receptor antibodies. Signal abnormality was most common in the limbic system (28/85, 33%); 1/68 (1.5%) had susceptibility artifacts. Brainstem and cerebellar involvement were more common in group 1, while leptomeningeal enhancement was more common in group 2.

CONCLUSIONS

Sixty-one percent of patients with autoimmune encephalitis had abnormal brain MR imaging findings at symptom onset, most commonly involving the limbic system. Susceptibility artifact is rare and makes autoimmune encephalitis less likely as a diagnosis. Brainstem and cerebellar involvement were more common in group 1, while leptomeningeal enhancement was more common in group 2.

Small vessel childhood primary angiitis of the central nervous system with positive anti-glial fibrillary acidic protein antibodies: a case report and review of literature

BACKGROUND

Small vessel childhood primary angiitis of the central nervous system (SV-cPACNS) is a rare disease characterized by inflammation within small vessels such as arterioles or capillaries.

CASE PRESENTATION

We report a case of SV-cPACNS in an 8-year-old boy confirmed by brain biopsy. This patient was also incidentally found to have anti-glial fibrillary acidic protein (GFAP) antibodies in the cerebrospinal fluid (CSF) but had no evidence of antibody-mediated disease on brain biopsy. A literature review highlighted the rarity of SV-cPACNS and found no prior reports of CSF GFAP-associated SV-cPACNS in the pediatric age group.

CONCLUSION

We present the first case of biopsy proven SV-cPACNS vasculitis associated with an incidental finding of CSF GFAP antibodies. The GFAP antibodies are likely a clinically insignificant bystander in this case and possibly in other diseases with CNS inflammation. Further research is needed to determine the clinical significance of newer CSF autoantibodies such as anti-GFAP before they are used for medical decision-making in pediatrics.

[Clinical features of autoimmune glial fibrillary acidic protein astrocytopathy in children: an analysis of 34 cases]

OBJECTIVES

To study the clinical features of children with autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A).

METHODS

A retrospective analysis was performed on the medical data of 34 children with GFAP-A who attended the Department of Neurology, Children's Hospital of Chongqing Medical University, from January 2020 to February 2022. The medical data included clinical manifestations, cerebrospinal fluid features, imaging examination results, treatment, and prognosis.

RESULTS

The median age of onset was 8.4 (range 1.9-14.9) years for the 34 children with GFAP-A. The main clinical manifestations included headache (50%, 17/34), fever (47%, 16/34), visual impairment (47%, 16/34), and disturbance of consciousness (44%, 15/34). Abnormal cerebrospinal fluid results were observed in 19 children (56%, 19/34), among whom 8 children had positive autoantibody. The children with overlap syndrome had significantly higher recurrence rate and rate of use of immunosuppressant than those without overlap syndrome (P<0.05). About 77% (24/31) of the children had good response to immunotherapy, and only 1 child had poor prognosis.

CONCLUSIONS

Children with GFAP-A often have non-specific clinical symptoms and show good response to immunotherapy. Children with overlap syndrome have a high recurrence rate, and early application of immunosuppressants may help to prevent recurrence and alleviate symptoms.

A pediatric case of autoimmune glial fibrillary acidic protein astrocytopathy with unique brain imaging patterns and increased cytokines/chemokines

BACKGROUND

Autoimmune anti-glial fibrillary acidic protein (GFAP) astrocytopathy represents a new spectrum of autoimmune inflammatory central nervous system disorders. In recent years, there have been an increasing number of reports on pediatric patients with this disease other than those in Japan.

CASE REPORT

A 6-year-old previously healthy boy presented with fever persisting for approximately 10 days, consciousness disturbance, anorexia, and hyponatremia (Na, 121 mEq/L). Even after appropriate correction of hyponatremia, consciousness disturbance was prolonged and was accompanied by gait disturbance, visual hallucinations, and autonomic dysfunction (bradycardia and urinary dysfunction). On a plain MRI, T2-weighted and fluid-attenuated inversion recovery images showed abnormal hyperintense lesions in the bilateral basal ganglia, thalamus, and periventricular white matter. The cerebrospinal fluid was positive for anti-GFAP antibody before treatment, and cytokines/chemokines were increased. He received three courses of intravenous methylprednisolone, followed by gradually tapered oral prednisolone for 6 months, without relapse after 1 year of observation.

CONCLUSION

In cases of autoimmune encephalitis with prolonged consciousness disturbance, hyponatremia, urinary dysfunction, and MRI findings with hyperintensities in the bilateral basal ganglia, thalamus, and periventricular white matter, anti-glial fibrillary acidic protein antibodies should be examined.

Characteristics of Movement Disorders in Patients with Autoimmune GFAP Astrocytopathy

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy (GFAP-A) is a type of autoimmune corticosteroid-responsive meningoencephalitis that occurs with or without myelitis. Movement disorders have been reported in GFAP-A patients but have not been characterized. In this study, we examined the characteristics of movement disorders in GFAP-A patients. We retrospectively reviewed clinical data from 87 consecutive patients with GFAP-A attending Gifu University Hospital in Japan. We compared the demographics, clinical features, cerebrospinal fluid characteristics, and neuroimaging findings from patients with and without movement disorders. Seventy-four patients (85%) had movement disorders, including ataxia (49%), tremor (45%), myoclonus (37%), dyskinesia (2%), opsoclonus (2%), rigidity (2%), myokymia (1%), and choreoathetosis (1%). GFAP-A patients with movement disorders were significantly older than those without. Movement disorders are therefore common in GFAP-A patients, and the main types of movement disorders observed in this population were ataxia, tremor, and myoclonus. These abnormal movements can serve as clinical features that facilitate the early diagnosis of GFAP-A. Elderly GFAP-A patients are more likely to have movement disorder complications than younger patients.

Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy in Children: A Retrospective Analysis of 35 Cases

Objective

To analyze the clinical manifestations, imaging, electroencephalography, treatment, and prognosis of 35 cases of autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A) in children.

Methods

Children hospitalized in the Department of Neurology, Hunan Children’s Hospital, China, between January 2015 and June 2021, owing to autoimmune diseases of the central nervous system were subjected to a cell-based assay (CBA). The assay identified 40 children positive for GFAP-immunoglobulin (Ig)G antibodies in the serum and/or the cerebrospinal fluid. Based on clinical manifestations and imaging characteristics, five children who were only positive for GFAP-IgG antibodies in serum were excluded, and the remaining 35 children were diagnosed with autoimmune GFAP-A. The clinical data derived from the 35 children were retrospectively analyzed.

Results

A total of 35 children, including 23 males and 12 females with a mean age of 6.3 ± 0.6 years, manifested clinical symptoms of fever (62.9%), headache (42.9%), convulsions (42.9%), abnormal mental behavior (51.4%), disorders of consciousness (54.3%), visual disturbance (22.9%), ataxia (11.4%), paralysis (40%), and autonomic dysfunction (25.7%). One child exhibited only the clinical symptom of peripheral facial nerve palsy. Eleven out of 35 children were also positive for other antibodies. In addition to the common overlapping autoimmune syndromes, one case of autoimmune GFAP-A also manifested as Bickerstaff’s brainstem encephalitis. Linear periventricular enhancement upon MRI was significantly less frequent in children (8.5%) than in adults. In pediatric patients, MRI contrast enhancement was principally seen in the meninges and brain lobes. Although repeated relapse (17.1%) and sequelae symptoms (20%) occurred in some cases, most children showed a favorable prognosis. Spearman’s rank correlation showed that the antibody titer was not significantly associated with the severity of the initial disease conditions.

Conclusions

The disease diagnosis in children seropositive for GFAP antibodies only should receive a comprehensive diagnosis based on their clinical symptoms, imaging, electroencephalographic characteristics, and treatment responses. Some patients with relapses should receive repeated gamma globulin and corticosteroid therapy or the addition of immunosuppressants to their therapeutic regimen, and slow-dose tapering of corticosteroids and extended treatment are recommended for patients with overlapping autoimmune syndromes.

Clinical, neuroradiological, diagnostic and prognostic profile of autoimmune glial fibrillary acidic protein astrocytopathy: A pooled analysis of 324 cases from published data and a single-center retrospective study

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a recently defined autoimmune meningoencephalomyelitis, associated with GFAP-IgG antibody. A pooled analysis of 324 cases from published literature and a retrospective single-center study were performed, firstly reveals the possibility that patients with myelitic lesions respond better to initial immunotherapy, but are prone to relapse, suggesting a more aggressive and long-term immunosuppressive medication for them. Moreover, our results showed using tacrolimus at maintenance stage exhibited a less tendency to relapse, providing a possibly new choice to future clinical treatments.

Autoimmune Encephalitis in Children: A Case Series at a Tertiary Care Center

Autoimmune encephalitis is the third most common cause of encephalitis in children. We provide a detailed account of presenting symptoms, diagnosis, and response to treatment in pediatric autoimmune encephalitis patients evaluated at University of California San Francisco within a 2.5-year period. Eleven were identified: anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis (n = 4), antibody-negative autoimmune encephalitis (n = 4), steroid-responsive encephalopathy associated with thyroiditis (SREAT) (n = 2), and glial fibrillary acidic protein (GFAP)-associated encephalitis (n = 1). Most common presenting symptoms included seizures and behavior changes (54%). More than 90% of patients showed improvement following first-line immunotherapy (high-dose corticosteroids, intravenous immunoglobulin, and/or plasma exchange). A total of 64% received second-line treatment with rituximab, cyclophosphamide, or mycophenolate mofetil. One patient with NMDAR encephalitis died despite escalating immunotherapy. None of the patients showed complete recovery after median follow-up of 9 months (range 0.5-66). Children with autoimmune encephalitis have a diverse clinical presentation and may lack an identifiable autoantibody. Majority of patients show a good response to immunotherapy; however, recovery can be delayed.

Autoimmune glial fibrillary acidic protein astrocytopathy mimics infectious meningitis: Two case reports

BACKGROUND

Autoimmune glial fibrillary acidic protein astrocytopathy (A-GFAP-A) has been recently characterized as a novel autoimmune central nervous system (CNS) disorder with GFAP antibody as the biomarker. However, nonspecific symptoms of A-GFAP-A contribute to misdiagnosis.

CASE PRESENTATION

The patients presented with initial symptoms of fever, headache, and nuchal rigidity. Case 1 exhibited mild signs of irritability, active tendon reflexes, and dysuria; case 2 had transient loss of consciousness. Cerebrospinal fluid (CSF) revealed lymphocytosis, elevated protein level, and decreased glucose level. Magnetic resonance imaging (MRI) revealed radial gadolinium enhancement perpendicular to the lateral ventricle. Viral meningitis or tubercular meningitis was suspected. However, their inflammatory and pathogenic indicators showed no abnormal changes, and empirical antibiotic and antiviral drugs did not result in remarkable recovery. Subsequently, cases were detected with a strongly positive expression of GFAP antibody in CSF and the symptoms improved dramatically after high-dose methylprednisolone pulse treatment.

CONCLUSION

A-GFAP-A with meningitis-like symptoms could initially masquerade as intracranial infection, and prompt detection of GFAP antibody is essential for differentiation.

Mild Encephalitis/Encephalopathy with reversible splenial lesion syndrome: An unusual presentation of anti-GFAP astrocytopathy

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a rare recently defined antibody-mediated encephalitis. Meningo-encephalomyelitis presentation is frequent with lymphocytic pleiocytosis in the cerebro-spinal fluid and brain MRI classically demonstrates in 50% of cases, a linear perivascular enhancement extending radially from the ventricles. Here, we describe 2 cases of pediatric autoimmune GFAP astrocytopathy with limbic encephalitis presentation and peculiar MRI characteristics: one with normal MRI and the second suggestive of Mild Encephalitis/Encephalopathy with reversible splenial lesion syndrome (MERS). These two cases illustrate that anti-GFAP antibodies should be sought in children presenting limbic encephalitis with a normal and/or MERS suggestive MRI, as treatment strategies may differ.

Autoimmune glial fibrillary acidic protein astrocytopathy

Purpose of review

To describe a recently characterized autoimmune, inflammatory central nervous system (CNS) disorder known as autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy.

Recent findings

Affected patients present with symptoms of one or more of meningitis (headache and neck ache), encephalitis (delirium, tremor, seizures, or psychiatric symptoms), and myelitis (sensory symptoms and weakness). Optic disc papillitis (blurred vision) is common. CNS inflammation is evident in characteristic T1 postgadolinium enhancement of GFAP-enriched CNS regions, and lymphocytic cerebrospinal fluid (CSF) white cell count elevation. CSF is more reliable than serum for GFAP-immunoglobulin G (IgG) testing. Ovarian teratoma commonly coexists, particularly among patients with accompanying N-methyl-D-aspartate receptor or aquaporin-4 autoimmunity. Parainfectious autoimmunity is suspected in some other patients, though the culprit organism is rarely verified. Pathophysiologic relevance of T cells is underscored by neuropathology and cases of dysregulated T-cell function (HIV or checkpoint inhibitor cancer therapy). Corticosteroid-responsiveness is a hallmark of the disease. Relapses occur in approximately 20% of patients, necessitating transition to a steroid-sparing drug. Reported outcomes vary, though in the authors’ experience, early and sustained intervention usually portends recovery.

Summary

Autoimmune GFAP astrocytopathy is a treatable autoimmune CNS disease diagnosable by GFAP-IgG testing in CSF. This disease presents opportunities to explore novel mechanisms of CNS autoimmunity and inflammation.

Glial Fibrillary Acidic Protein Astrocytopathy in Pediatric Patients: A Retrospective Study

Autoimmune glial fibrillary acidic protein astrocytopathy is a novel form of autoimmune meningoencephalitis related to GFAP autoantibodies. This condition is still being characterized, and few pediatric patients have been identified. Here, we report three patients presenting with fever, nausea, and headache, following progressive disturbance of consciousness, limb weakness, dyspnea, or urine retention. MRI analysis revealed that T2-hyperintense lesions, or enhancement of the meninges and spinal cord. CSF and serum analyses revealed they were positive for GFAP antibody, confirming GFAP astrocytopathy diagnosis. Treating the patients with IVIG, with or without intravenous steroids, gradually improved their clinical symptoms. Our findings indicate that GFAP astrocytopathy should be considered in children who are clinically diagnosed with meningoencephalitis, whether or not myelitis is present, and if the MRI reveals enhancement of meninges or spinal cord, T2-hyperintense lesions, or a pattern of linear perivascular gadolinium enhancement. Suspected cases should be tested for GFAP antibody as soon as possible because these patients may benefit from immunotherapy.