Article Text

PDF
Letter
IgM MGUS and Waldenstrom-associated anti-MAG neuropathies display similar response to rituximab therapy
  1. Marta Campagnolo1,
  2. Renato Zambello2,
  3. Eduardo Nobile-Orazio3,
  4. Luana Benedetti4,
  5. Girolama Alessandra Marfia5,
  6. Nilo Riva6,
  7. Francesca Castellani1,
  8. Mariangela Bianco3,
  9. Alessandro Salvalaggio1,
  10. Martina Garnero4,
  11. Marta Ruiz1,
  12. Giorgia Mataluni5,
  13. Raffaella Fazio6,
  14. Mario Ermani1,
  15. Chiara Briani1
  1. 1 Department of Neurosciences, University of Padova, Padua, Italy
  2. 2 Medicine, Hematology and Clinical Immunology Unit, University of Padova, Padua, Italy
  3. 3 Second Neurology, Humanitas Clinical and Research Centre, Department of Medical Biotechnology and Translational Medicine, Milan University, Milan, Italy
  4. 4 Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova and IRCCS AOU San Martino-IST, Genoa, Italy
  5. 5 Neurology COU, Department of Systems Medicine, University of Tor Vergata, Rome, Italy
  6. 6 Department of Neurology, San Raffaele Scientific Institute, Milan, Italy
  1. Correspondence to Dr Chiara Briani, Department of Neurosciences, University of Padova, Via Giustiniani 5, 35128 Padova - Italy; chiara.briani{at}unipd.it

Statistics from Altmetric.com

Introduction

No adequate immunotherapy has so far been shown to be effective in anti-myelin-associated glycoprotein (MAG) antibody neuropathy.1 Rituximab was assessed in two randomised controlled trials, both including only patients with monoclonal gammopathy of undetermined significance (MGUS), with Waldenstrom’s macroglobulinaemia (WM) being an exclusion criterion.2

The aim of our multicentre retrospective study was to assess whether the response to rituximab in patients with anti-MAG antibody neuropathy would differ according to the associated haematological condition.

Methods

We reviewed the clinical and laboratory features of 33 patients (21 men, mean age at time of therapy: 64.6±10.3, range: 41–87, mean neuropathy duration at time of therapy: 4.67 years±4.82, range: 0.5–17) with anti-MAG antibody neuropathy who underwent therapy with rituximab single agent in five Italian neurological centres. Twenty-five (73.5%) patients had Immunoglobulin M (IgM) MGUS and 8/33 had WM, according to bone marrow biopsy. The mean age was significantly different in the two groups (62.5±10.3 years in MGUS vs 70.5±7.9 years in WM, p=0.04). The mean neuropathy duration was 4.56±4.8 years in MGUS versus 5.6±5.1 years in WM (p=0.62, Mann-Whitney U test).

Anti-MAG antibodies were assayed by ELISA (Bühlmann Laboratories AG) (28 patients) or Western blot (5 patients). The median antibodies titre was 51 200 (range: 7500–800 000) in MGUS and 56 000 (range: 11 126–600 000) in patients with WM. Patients with low (<10 000 Bühlmann Titer Units) titre were included for clinical and neurophysiological features consistent with anti-MAG neuropathy. Antibody titres were not retrievable in two patients.

Twenty patients were therapy-naive, while 13 …

View Full Text

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.