Jean-Christophe Antoine1, Nadia Boutahar2, François Lassablière3, Evelyne Reynaud4, Karine Ferraud5, Véronique Rogemond6, Stéphane Paul7, Jérôme Honnorat8, Jean-Philippe Camdessanché1. 1. Service de Neurologie, CHU de Saint-Etienne, Saint-Etienne, France Université de Saint-Etienne Jean Monnet, Saint-Etienne, France Centre de Référence Maladies Neuromusculaires Rares, CHU de Saint-Etienne, Saint-Etienne, France Centre de Référence Français des Syndromes Neurologiques Paraneoplasiques, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France Lyon Centre de Recherche de Neuroscience INSERM U1028/CNRS UMR 5292, Lyon, France. 2. Université de Saint-Etienne Jean Monnet, Saint-Etienne, France Lyon Centre de Recherche de Neuroscience INSERM U1028/CNRS UMR 5292, Lyon, France. Laboratoire de Biochimie, CHU de Saint-Etienne, Saint-Etienne, France. 3. Department of Neurosciences, Université de Saint-Etienne, Saint-Etienne, France. 4. Laboratoire de Biochimie, CHU de Saint-Etienne, Saint-Etienne, France. 5. Service de Neurologie, CHU de Saint-Etienne, Saint-Etienne, France. 6. Centre de Référence Français des Syndromes Neurologiques Paraneoplasiques, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France Lyon Centre de Recherche de Neuroscience INSERM U1028/CNRS UMR 5292, Lyon, France. 7. Université de Saint-Etienne Jean Monnet, Saint-Etienne, France Centre de Référence Français des Syndromes Neurologiques Paraneoplasiques, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France Laboratoire d'Immunologie, CHU de Saint-Etienne, Saint-Etienne, France. 8. Centre de Référence Français des Syndromes Neurologiques Paraneoplasiques, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France Lyon Centre de Recherche de Neuroscience INSERM U1028/CNRS UMR 5292, Lyon, France. Université de Lyon-Université Claude Bernard Lyon 1, Lyon, France.
Abstract
BACKGROUND: Immunological mechanisms are suspected in sensory neuropathy (SN) occurring with systemic autoimmune diseases and in some idiopathic cases, but so far there are no antibodies (Abs) identifying these neuropathies. METHODS: In the search for such specific antibodies, serum samples were collected from 106 patients with SN of these 72 fulfilled the diagnosis criteria of sensory neuronopathy (SNN) and 211 control subjects including patients with sensorimotor neuropathies, other neurological diseases (ONDs), systemic autoimmune diseases and healthy blood donors. RESULTS: In the first step, a protein array with 8000 human proteins allowed identification of the intracellular domain of the fibroblast growth factor receptor 3 (FGFR3) as a target of Abs in 7/16 SNN and 0/30 controls. In the second step, an ELISA method was used to test the 317 patients and controls for anti-FGFR3 Abs. Abs were detected in 16/106 patients with SN and 1/211 controls (p<0.001). Among the 106 patients with SN, anti-FGFR3 Abs were found in 11/38 patients with autoimmune context, 5/46 with idiopathic neuropathy and 0/22 with neuropathy of other aetiology (p=0.006). The only control patient with anti-FGFR3 Abs had lupus and no recorded neuropathy. Sensitivity, specificity, and positive and negative predictive values of anti-FGFR3 Abs for a diagnosis of idiopathic or dysimmune SN were 19%, 99.6%, 94.1% and 77.3%, respectively. A cell-based assay confirmed serum reactivity against the intracellular domain of FGFR3. The neuropathy in patients with anti-FGF3 Abs was non-length dependent in 87% of patients and fulfilled the criteria of probable SNN in 82%. Trigeminal nerve involvement and pain were frequent features. CONCLUSIONS: A anti-FGFR3 Abs identify a subgroup of patients with SN in whom an underlying autoimmune disorder affecting sensory neurons in the dorsal root and trigeminal nerve ganglia is suspected. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
BACKGROUND: Immunological mechanisms are suspected in sensory neuropathy (SN) occurring with systemic autoimmune diseases and in some idiopathic cases, but so far there are no antibodies (Abs) identifying these neuropathies. METHODS: In the search for such specific antibodies, serum samples were collected from 106 patients with SN of these 72 fulfilled the diagnosis criteria of sensory neuronopathy (SNN) and 211 control subjects including patients with sensorimotor neuropathies, other neurological diseases (ONDs), systemic autoimmune diseases and healthy blood donors. RESULTS: In the first step, a protein array with 8000 human proteins allowed identification of the intracellular domain of the fibroblast growth factor receptor 3 (FGFR3) as a target of Abs in 7/16 SNN and 0/30 controls. In the second step, an ELISA method was used to test the 317 patients and controls for anti-FGFR3 Abs. Abs were detected in 16/106 patients with SN and 1/211 controls (p<0.001). Among the 106 patients with SN, anti-FGFR3 Abs were found in 11/38 patients with autoimmune context, 5/46 with idiopathic neuropathy and 0/22 with neuropathy of other aetiology (p=0.006). The only control patient with anti-FGFR3 Abs had lupus and no recorded neuropathy. Sensitivity, specificity, and positive and negative predictive values of anti-FGFR3 Abs for a diagnosis of idiopathic or dysimmune SN were 19%, 99.6%, 94.1% and 77.3%, respectively. A cell-based assay confirmed serum reactivity against the intracellular domain of FGFR3. The neuropathy in patients with anti-FGF3 Abs was non-length dependent in 87% of patients and fulfilled the criteria of probable SNN in 82%. Trigeminal nerve involvement and pain were frequent features. CONCLUSIONS: A anti-FGFR3 Abs identify a subgroup of patients with SN in whom an underlying autoimmune disorder affecting sensory neurons in the dorsal root and trigeminal nerve ganglia is suspected. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/