title: Diagnosis of small fiber neuropathy: A comparative study of five neurophysiological tests.
abstract: The diagnosis of small fiber neuropathy (SFN) is a challenge for clinical neurophysiology. Conventional nerve conduction studies are inappropriate for this purpose and therefore various neurophysiological tests have been proposed. In this study, we compared the diagnostic value of five of these tests in 87 patients with clinically definite (n=33) or possible (n=54) SFN related to amyloid neuropathy secondary to transthyretin gene mutation or monoclonal gammopathy (n=30), primary Sjögren's syndrome (n=20), Fabry's disease (n=2), or unknown cause (n=35). Neurophysiological tests included quantitative sensory testing with determination of warm and cold detection thresholds (WDT, CDT), recording of laser-evoked potentials (LEP) and sympathetic skin responses (SSRs), and measurement of electrochemical skin conductance (ESC) using Sudoscan(®) device. All tests were performed at the four extremities (hands and feet). All patients with clinically definite SFN and 70% of the patients with possible SFN had at least one abnormal test. The LEP was the most sensitive test (altered in 79% of the patients with at least one abnormal test), followed by ESC (61%), WDT (55%), SSR (41%), and CDT (32%). The combination of LEP, assessing A-delta sensory fibers, WDT, assessing sensory C fibers, and ESC, assessing autonomic C fibers, appears a relevant approach for the diagnosis of SFN. Compared to SSR and CDT, these three tests, LEP, WDT, and ESC, had a significantly better diagnostic sensitivity and their combination further improved diagnostic accuracy.
authors.affiliation: EA 4391, faculté de médecine de Créteil, université Paris-Est de Créteil, 8, avenue du Général-Sarrail, 94010 Créteil, France; Réseau Amylose-Henri-Mondor, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France; Service de physiologie-explorations fonctionnelles, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France. Electronic address: jean-pascal.lefaucheur@hmn.aphp.fr.
authors.forename: J-P
authors.initials: JP
authors.lastname: Lefaucheur
authors.affiliation: Service de physiologie-explorations fonctionnelles, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: A
authors.initials: A
authors.lastname: Wahab
authors.affiliation: Réseau Amylose-Henri-Mondor, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France; Service de neurologie, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: V
authors.initials: V
authors.lastname: Planté-Bordeneuve
authors.affiliation: Service de médecine interne 2, hôpital Lariboisière, université Paris VII, Assistance publique-Hôpitaux de Paris, 2, rue Ambroise-Paré, 75010 Paris, France.
authors.forename: D
authors.initials: D
authors.lastname: Sène
authors.affiliation: Service de physiologie-explorations fonctionnelles, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: I
authors.initials: I
authors.lastname: Ménard-Lefaucheur
authors.affiliation: Service de physiologie-explorations fonctionnelles, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: D
authors.initials: D
authors.lastname: Rouie
authors.affiliation: Service de physiologie-explorations fonctionnelles, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: D
authors.initials: D
authors.lastname: Tebbal
authors.affiliation: EA 4391, faculté de médecine de Créteil, université Paris-Est de Créteil, 8, avenue du Général-Sarrail, 94010 Créteil, France; Service de neurologie, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: H
authors.initials: H
authors.lastname: Salhi
authors.affiliation: EA 4391, faculté de médecine de Créteil, université Paris-Est de Créteil, 8, avenue du Général-Sarrail, 94010 Créteil, France; Service de neurologie, hôpital Henri-Mondor, Assistance publique-Hôpitaux de Paris, 51, avenue de Lattre-de-Tassigny, 94010 Créteil, France.
authors.forename: A
authors.initials: A
authors.lastname: Créange
authors.affiliation: EA 4391, faculté de médecine de Créteil, université Paris-Est de Créteil, 8, avenue du Général-Sarrail, 94010 Créteil, France; Service d'explorations fonctionnelles, CHU Habib-Bourguiba, Sfax, Tunisia.
authors.forename: H
authors.initials: H
authors.lastname: Zouari
authors.affiliation: EA 4391, faculté de médecine de Créteil, université Paris-Est de Créteil, 8, avenue du Général-Sarrail, 94010 Créteil, France; EA 2363, UFR SMBH, université Paris 13, 125, rue de Stalingrad, 93000 Bobigny, France; Service de physiologie, explorations fonctionnelles et médecine du sport, hôpital Avicenne, Assistance publique-Hôpitaux de Paris, 125, rue de Stalingrad, 93000 Bobigny, France.
authors.forename: S
authors.initials: S
authors.lastname: Ng Wing Tin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D028227:Amyloid Neuropathies, Familial / Q000175:diagnosis / Q000473:pathology; D005071:Evoked Potentials; D005260:Female; D005712:Galvanic Skin Response; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009422:Nervous System Diseases / Q000175:diagnosis* / Q000473:pathology*; D009431:Neural Conduction / Q000502:physiology; D009460:Neurologic Examination / Q000379:methods*; D012016:Reference Values; D012684:Sensory Thresholds; D055815:Young Adult
keywords: Amyloid neuropathy; Fabry's disease; Laser-evoked potentials; Maladie de Fabry; Neuropathie amyloïde; Neuropathie des petites fibres; Potentiels évoqués laser; Quantitative sensory testing; Réponses cutanées sympathiques; Sjögren's syndrome; Small fiber neuropathy; Sudoscan(®); Sympathetic skin responses; Syndrome de Sjögren; Étude quantifiée de la sensibilité