title: Non-anti-MAG DADS neuropathy as a variant of CIDP: clinical, electrophysiological, laboratory features and response to treatment in 10 cases.
abstract: OBJECTIVE
  Some patients within the spectrum of chronic inflammatory demyelinating polyradiculoneuropathies (CIDP) have distal acquired demyelinating symmetric (DADS) neuropathy, usually associated with anti-myelin-associated-glycoprotein (MAG) IgM monoclonal gammopathy. The aim of this retrospective study was to investigate patients with DADS neuropathy without anti-MAG antibodies, and study their response to immunotherapy.
  
  
  METHODS
  Patients were selected on the basis of (i) 'Definite CIDP' according to the EFNS/PNS Guideline criteria, (ii) The presence of disproportionately prolonged motor latencies resulting in a terminal latency index (TLI) ≤ 0.25 in at least two motor nerves and (iii) The absence of anti-MAG antibodies on ELISA. Response to immunotherapy was defined as persistent improvement by at least one point on the INCAT disability score.
  
  
  RESULTS
  Data from 146 CIDP patients were analysed, and 10 patients were included. Six had clinically pure sensory neuropathy, and four had sensorimotor neuropathy. Ataxia was present in nine patients, generalized areflexia in seven and postural tremor in two. Five of the 10 patients had abnormal sensory potentials only in the upper limbs. An associated condition was found in nine patients: two chronic lymphocytic leukaemias, four IgG monoclonal gammopathies (one associated with non-Hodgkin's lymphoma) and two IgM monoclonal gammopathies of unknown significance. Patients were mostly improved with intravenous immunoglobulin (IVIg), corticosteroids, plasma exchanges, or a combination thereof.
  
  
  CONCLUSIONS
  DADS neuropathy without anti-MAG antibodies is more likely to be considered a variant of CIDP. In addition, such patients should be systematically investigated for an associated haematological or immunological condition.
authors.affiliation: Centre de Référence Maladies Neuromusculaires Rares, Hôpital Pitié-Salpêtrière and Université Paris VI, Paris, France.
authors.forename: S
authors.initials: S
authors.lastname: Larue
authors.forename: F
authors.initials: F
authors.lastname: Bombelli
authors.forename: K
authors.initials: K
authors.lastname: Viala
authors.forename: J
authors.initials: J
authors.lastname: Neil
authors.forename: T
authors.initials: T
authors.lastname: Maisonobe
authors.forename: P
authors.initials: P
authors.lastname: Bouche
authors.forename: L
authors.initials: L
authors.lastname: Musset
authors.forename: E
authors.initials: E
authors.lastname: Fournier
authors.forename: J M
authors.initials: JM
authors.lastname: Léger
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000097:blood; D004568:Electrodiagnosis / Q000379:methods; D005260:Female; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007167:Immunotherapy / Q000379:methods; D007945:Leukemia, Lymphoid / Q000150:complications / Q000276:immunology; D008297:Male; D008875:Middle Aged; D018992:Myelin-Associated Glycoprotein / Q000276:immunology*; D010265:Paraproteinemias / Q000150:complications / Q000276:immunology; D010525:Peripheral Nerves / Q000276:immunology* / Q000503:physiopathology*; D010956:Plasmapheresis; D020277:Polyradiculoneuropathy, Chronic Inflammatory Demyelinating / Q000175:diagnosis* / Q000188:drug therapy / Q000276:immunology; D012189:Retrospective Studies
chemical_list: D000305:Adrenal Cortex Hormones; D001323:Autoantibodies; D016756:Immunoglobulins, Intravenous; D018992:Myelin-Associated Glycoprotein