Eosinophilic vasculitis of the spinal cord associated with Churg-Strauss syndrome

SAFit2 reduces neuroinflammation and ameliorates nerve injury-induced neuropathic pain

Background

Neuropathic pain is experienced worldwide by patients suffering from nerve injuries, infectious or metabolic diseases or chemotherapy. However, the treatment options are still limited because of low efficacy and sometimes severe side effects. Recently, the deficiency of FKBP51 was shown to relieve chronic pain, revealing FKBP51 as a potential therapeutic target. However, a specific and potent FKBP51 inhibitor was not available until recently which hampered targeting of FKBP51.

Methods

In this study, we used the well-established and robust spared nerve injury model to analyze the effect of SAFit2 on nerve injury-induced neuropathic pain and to elucidate its pharmacodynamics profile. Therefore, the mice were treated with 10 mg/kg SAFit2 after surgery, the mice behavior was assessed over 21 days and biochemical analysis were performed after 14 and 21 days. Furthermore, the impact of SAFit2 on sensory neurons and macrophages was investigated in vitro.

Results

Here, we show that the FKBP51 inhibitor SAFit2 ameliorates nerve injury-induced neuropathic pain in vivo by reducing neuroinflammation. SAFit2 reduces the infiltration of immune cells into neuronal tissue and counteracts the increased NF-κB pathway activation which leads to reduced cytokine and chemokine levels in the DRGs and spinal cord. In addition, SAFit2 desensitizes the pain-relevant TRPV1 channel and subsequently reduces the release of pro-inflammatory neuropeptides from sensory neurons.

Conclusions

SAFit2 ameliorates neuroinflammation and counteracts enhanced neuronal activity after nerve injury leading to an amelioration of nerve injury-induced neuropathic pain. Based on these findings, SAFit2 constitutes as a novel and promising drug candidate for the treatment of nerve injury-induced neuropathic pain.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-022-02615-7.

Neurological impact of eosinophilic granulomatosis with polyangiitis

Nervous system (NS) affection may occur in Eosinophilic Granulomatosis with Polyangiitis (EGPA), but its clinical manifestations and pathophysiology are rarely described. Our aims are to characterize central and peripheral NS (CNS/PNS) involvement and compare biological markers in EGPA patients with and without neurological manifestations. Retrospective observational study, including EGPA patients with and without neurological manifestations. Demographics, clinical data, and immunological markers were analyzed. Descriptive and inferential statistics were performed. Sixteen patients were included; 11 (68.8%) of whom were male, with a mean age of 63.38 years; 8 with (Group 1) and 8 without (Group 2) neurological findings. Neurological impairment preceded EGPA diagnosis in 5 patients, and occurred during follow-up in 3 patients after a median of 4.0 years. CNS manifestations observed were stroke (n = 2), bilateral central retinal artery occlusion (n = 1), and compressive dorsal myelopathy due to extradural granulation tissue (n = 1). PNS manifestations were axonal polyneuropathy (n = 3), sensorineural hearing loss (n = 3), and multiplex mononeuropathy (n = 1). Two patients had both PNS and CNS involvement. There were no statistical differences regarding biological markers [eosinophil count, myeloperoxidase (MPO) antibodies titers] between the 2 groups. One patient from Group 1 was unresponsive to treatment and permanent neurological sequelae were observed in 7 cases. EGPA-related NS involvement can be heterogeneous and is responsible for long-term sequelae. In our sample, the main neurological scenarios were peripheral neuropathy, VIII cranial nerve neuropathy, ischemic lesions and compressive myelopathy. Patients with and without neurological manifestations did not differ in eosinophilic count and MPO titer.

Hypereosinophilic syndrome with central nervous system involvement treated with anti-IL-5 therapy

Hypereosinophilic syndrome (HES) is a rare disorder characterized by a persistent eosinophilia with a multi-organ involvement including neurological manifestation. A 59-year-old man was referred from a neurosurgery unit with a spastic triparesis with predominant left side involvement, dissociated sensory loss to Th7, and metastasis-like lesions in a brain CT. MRI examination of the thoracic spine revealed an intraspinal T2-hyperintensive lesion with a subtle central gadolinium enhancement at Th4-Th8 level. MRI of the cervical spine showed a C1-Th1 long T2-hyperintensive lesion with a partial gadolinium enhancement and MRI of the brain revealed a large tumefactive T2-hyperintensive lesion in the right hemisphere. Blood tests showed an increased number of eosinophils (1790 cells/µl; 18.3%). Common causes of the eosinophilia were excluded. After corticosteroid treatment moderate neurological improvement was observed however in the brain MRI new T2-hyperintensive lesions were revealed. The patient was referred to the Department of Allergology and qualified for a treatment with mepolizumab, a monoclonal antibody against IL-5, with subsequent clinical and radiological improvement. To the best of our knowledge, this is the first case of hypereosinophilic syndrome with brain and spinal cord involvement treated with mepolizumab.

Anti-neutrophil cytoplasmic antibody associated central nervous system vasculitis with brain and spinal cord subarachnoid hemorrhage: A rare case report and review of the literature

This case report describes a 48-year old female who presented with altered mental status, lower extremity weakness, low back pain and a recent history of subjective fevers and night sweats found to have posterior parieto-occipital and spinal subarachnoid hemorrhage on imaging. Further work-up revealed vasculitic changes in the intracranial vasculature and the external carotid artery on angiography. She also demonstrated positivity for perinuclear anti-neutrophil cytoplasmic (p-ANCA) antibodies overall consistent with ANCA associated central nervous system vasculitis (AAV). The present case describes a rare and new presentation of AAV that caused both a cerebral and spinal subarachnoid hemorrhage. There has been no documentation of spinal subarachnoid hemorrhage associated with primary or secondary vasculitis in the literature. Ultimately, this case demonstrates the important finding that AAV can have spinal cord manifestations and cervical vasculature involvement along with the more classic intra-cranial vasculitis findings.

Central nervous system involvement in eosinophilic granulomatosis with polyangiitis (Churg-Strauss): Report of 26 patients and review of the literature

BACKGROUND

Although peripheral nervous system involvement is common in eosinophilic granulomatosis with polyangiitis (EGPA), central nervous system (CNS) manifestations are poorly described. This study aimed to describe CNS involvement in EGPA.

PATIENTS AND METHODS

This retrospective, observational, multicenter study included patients with EGPA and CNS involvement affecting cranial nerves, brain and/or spinal cord. We also undertook a systematic literature review.

RESULTS

We analyzed 26 personal cases and 62 previously reported cases. At EGPA diagnosis, asthma was noted in 97%, eosinophilia in 98%, peripheral neuropathy in 55% and cardiac involvement in 41%. 38/71 (54%) were ANCA-positive, with a perinuclear-labeling pattern and/or anti-MPO specificity. CNS was involved in 86% at EGPA diagnosis, preceded EGPA in 2%, and occurred during follow-up in 12% after a median of 24months. Main neurological manifestations were ischemic cerebrovascular lesions in 46 (52%), intracerebral hemorrhage and/or subarachnoid hemorrhage in 21 (24%), loss of visual acuity in 28 (33%) (15 with optic neuritis, 9 with central retinal artery occlusion, 4 with cortical blindness), and cranial nerves palsies in 18 (21%), with 25 patients having ≥1 of these clinical CNS manifestations. Among the 81 patients with assessable neurological responses, 43% had complete responses without sequelae, 43% had partial responses with long-term sequelae and 14% refractory disease. After a mean follow-up of 36months, 11 patients died including 5 from intracerebral hemorrhages.

CONCLUSION

EGPA-related CNS manifestations form 4 distinct neurological pictures: ischemic lesions, intracerebral hemorrhages, cranial nerve palsies and loss of visual acuity. Such manifestation should prompt practitioners to consider EGPA in such conditions. Long-term neurological sequelae were common, and intracerebral hemorrhages had the worst prognostic impact.

Clinical Features of Neuropsychiatric Syndromes in Systemic Lupus Erythematosus and Other Connective Tissue Diseases

Systemic lupus erythematosus (SLE) and related disorders are chronic inflammatory diseases characterized by abnormalities and, in some cases, even complete failure of immune responses as the underlying pathology. Although almost all connective tissue diseases and related disorders can be complicated by various neuropsychiatric syndromes, SLE is a typical connective tissue disease that can cause neurological and psychiatric syndromes. In this review, neuropsychiatric syndromes complicating connective tissue diseases, especially SLE are outlined, and pathological and other conditions that should be considered in the differential diagnosis are also discussed.

Mini-review: Eosinophils, a Useful Diagnostic Clue in Surgical Neuropathology

<p>Eosinophils are one of the polymorphonuclear granulocytes derived from bone marrow stem cells, and they contain many small cytoplasmic granules that stain bright red with eosin or brick-red with Romanowsky staining. Eosinophilic infiltration is also present in various human central nervous system (CNS) diseases such as parasitic infection, transverse myelitis, vasculitis, Langerhans cell histiocytosis, glioblastoma and etc... Due to the morphologic and functional characteristics, the presence of eosinophils in certain lesions may provide useful diagnostic clues in the right clinical setting. Consideration of this finding may facilitate the diagnosis of CNS pathologic lesions, especially in a small specimen such as a stereotactic biopsy.</p>

Eosinophilic myelitis in the cervical cord mimicking intramedullary cord tumor

Eosinophilic myelitis (EM) or atopic myelitis is a rare disease characterized by a myelitic condition in the spinal cord combined with allergic process. This disease has specific features of elevated serum IgE level, active reaction to mite specific antigen and stepwise progression of mostly the sensory symptoms. Toxocariasis can be related with a form of EM. This report describes two cases of cervical eosinophilic myelitis initially considered as intramedullary tumors. When a differential diagnosis of the intramedullary spinal cord lesion is in doubt, evaluation for eosinophilic myelitis and toxocariasis would be beneficial.