Case Report: Ofatumumab treatment in a patient with rituximab-intolerant refractory autoimmune GFAP astrocytopathy

Autoimmune glial fibrillary acidic protein astrocytopathy misdiagnosed as intracranial infectious diseases: case reports and literature review

Background

Autoimmune glial fibrillary acidic protein astrocytopathy (A-GFAP-A) is an autoimmune central nervous system(CNS) disease characterized by GFAP IgG as a biomarker. Several cases of individuals with A-GFAP-A initially misdiagnosed as infectious diseases of the central nervous system have been reported in research. We report three cases of A-GFAP-A misdiagnosed as viral meningitis or tuberculous meningitis (TBM). We summarize recent cases of A-GFAP-A misdiagnosed as central nervous system infections through a literature review.

Materials and methods

Three cases of A-GFAP-A were initially misdiagnosed as tuberculous or viral meningitis. Their diagnoses of A-GFAP-A were confirmed with positive GFAP-IgG in cerebrospinal fluid (CSF). We searched the PubMed database with the key words of "GFAP astrocytopathy", "GFAP autoimmunity", "GFAP autoantibody", "intracranial infection", "meningitis", "misdiagnose", and within the literature from Jan 1, 2015 to Mar 15, 2024, 40 cases with A-GFAP-A with positive GFAP-IgG in CSF who were previously misdiagnosed with intracranial infection were reported. The causes of misdiagnoses were summarized and analyzed.

Results

Case 1 was a 41-year-old female, presenting with headache, fever, diplopia, and altered consciousness level. Anti-tuberculosis treatment was ineffective. Finally, with positive GFAP IgG in CSF, she was diagnosed with A-GFAP-A. Case 2 was a 74-year-old male, presenting with fever, excessive sweating, fatigue, and memory loss. Anti-tuberculosis treatment was ineffective. With positive GFAP IgG in CSF, he was diagnosed with A-GFAP-A. Case 3 was a 54-year-old male, presenting with fever, personality changes, and memory decline. Antiviral treatment was ineffective. His diagnosis was revised to A-GFAP-A after testing positive for GFAP IgG in CSF. Our study summarized a total of 40 patients with A-GFAP-A who were initially misdiagnosed as intracranial infections. The most common clinical phenotypes among 40 patients were mimicked meningitis, meningoencephalitis, meningoencephalomyelitis, encephalitis and encephalomyelitis.

Conclusion

A-GFAP-A is a specific autoimmune meningoencephalomyelitis associated with GFAP-IgG, with lesions involved the brain, meninges, and spinal cord. It commonly presents with symptoms such as fever, headache, altered consciousness, tremor, seizures, and autonomic dysfunction. Brain MRI often shows characteristic linear perivascular radial enhancement perpendicular to the ventricles or nonspecific leptomeningeal enhancement. Early detection of GFAP-IgG in serum and CSF is essential for differential diagnosis.

Unveiling GFAP Astrocytopathy: Insights from Case Studies and a Comprehensive Review of the Literature

BACKGROUND

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy, which was first identified in 2016, is an immune-mediated inflammatory disorder of the nervous system characterized by antibodies targeting GFAP. The exact pathogenic mechanisms, as well as the role of anti-GFAP antibodies, remain unclear; however, it seems that neuroinflammation is mediated by specific CD8+ T-cells and that neoplasms or viral infections can act as the initial trigger. Although the clinical spectrum of the disease is broad and heterogenous, GFAP astrocytopathy most commonly presents as meningoencephalitis with or without myelitis. Other symptoms include headache, visual disturbances, extrapyramidal or brainstem syndromes, and psychiatric manifestations including psychosis. The disease has a characteristically favorable response to steroid treatment while relapses occur in approximately 20-30% of the patients.

METHODS

We present two cases of GFAP astrocytopathy admitted to our hospital: a 43-year-old male with persistent headache and a 59-year-old female with acute dysarthria and swallowing difficulties followed by cognitive and behavioral symptoms.

RESULTS

Additionally, we conduct a comprehensive review of the literature to elucidate the role of anti-GFAP antibodies in disease pathogenesis and examine imaging characteristics, clinical manifestations, and treatment options for this recently described neuroimmunological condition.

CONCLUSIONS

This review presents two unusual cases of GFAP-astrocytopathy and provides evidence for the pathogenesis, clinical presentation, imaging characteristics and treatment options of the disease.

Anti-SRP immune-mediated necrotizing myopathy responsive to ofatumumab: a case report

Background

Immune-mediated necrotizing myopathies (IMNM) is a rare disease that was first described in 2004. Due to the lack of large case series, there are no formal treatment recommendations for IMNM.

Methods

We presented a case of a 47-year-old woman who experienced progressive limb weakness, starting from the lower limbs and gradually affecting the upper limbs. She also reported experiencing dyspnea after engaging in daily activities. When she was admitted to the hospital, her upper limbs were almost unable to move and she could not stand even with support. Her Creatine kinase (CK) level significantly increased (> 3500 u/l). Electromyography showed myogenic damage, anti-Signal recognition particle (anti-SRP) and anti-Ro52 antibodies were highly positive. Pathological biopsy of the right biceps muscle showed necrotizing myopathy in the skeletal muscle. She was ultimately diagnosed with anti-SRP IMNN, and was given monotherapy with methylprednisolone and combination therapy with immunoglobulin, but her symptoms continued to worsen. The patient refused to bear the possible further liver dysfunction and blood system damage caused by Cyclophosphamide and Rituximab, and she chose to try to use Ofatumumab (OFA).

Results

After receiving three doses of OFA treatment without any adverse reactions, she reported that her muscle strength had basically recovered and she was able to walk independently. The B cells in the circulatory system have been depleted, and blood markers such as liver function have consistently remained within normal range. During the follow up, her activity tolerance continued to improve.

Discussion

We have presented a severe case of SRP-IMNM in which the patient showed poor response to conventional immunotherapy. However, rapid symptom relief was achieved with early sequential use of OFA treatment. This provides a new option for the treatment of SRP-IMNM, and more large-scale studies will be needed in the future to verify our results.