Neuroimaging markers of clinical progression in chronic inflammatory demyelinating polyradiculoneuropathy.

Background: One of the main goals of novel, noninvasive imaging techniques like high-resolution nerve ultrasound (HRUS) and corneal confocal microscopy (CCM) is the prediction of treatment response for patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).
Methods: A total of 17 patients with CIDP were examined prospectively at baseline and every 9 months over a period of 18 months using CCM to quantify corneal nerve degeneration markers and immune cell infiltration as well as HRUS to detect changes of the cross-sectional area (CSA) of the peripheral nerves. Additionally, skin biopsy of the distal and proximal leg as well as quantitative sensory testing were performed at the first follow-up visit.
Results: A value of more than 30 total corneal cells/mm ² in CCM at baseline identified patients with clinical progression with a sensitivity/specificity of 100% in our cohort. Corneal nerve fiber density and length remained low and stable over the study period and intra-epidermal fiber density was markedly reduced in the majority of the patients. Furthermore, an increase in Bochum ultrasound score (BUS), which summarizes the CSA of the ulnar nerve in Guyons' canal, the ulnar nerve in the upper arm, the radial nerve in the spiral groove and the sural nerve between the gastrocnemius muscle, and a maximum BUS of 4 at study initiation identified patients with disease progression (sensitivity 80%, specificity 88%).
Conclusions: BUS and corneal total cell infiltration seem to represent early markers for clinical progression in CIDP, thus having the potential to identify at-risk patients and impact treatment decisions.
Competing Interests: Conflicts of interest: Nina Kumowski, Lynn Eitner, Tineke Greiner, Anna Lena Fisse and Adnan Labedi report no disclosures. Dietrich Sturm received funding from the Ruhr University, Bochum (FoRUM-Program). Kalliopi Pitarokoili received travel funding and speaker honoraria from Biogen Idec, Novartis and Bayer Schering Pharma and funding from the Ruhr University, Bochum (FoRUM-Program). R. Gold has received consultation fees and speaker honoraria from Bayer Schering, Biogen Idec, Merck Serono, Novartis, Sanofi-Aventis and TEVA. He also acknowledges grant support from Bayer Schering, Biogen Idec, Merck Serono, Sanofi-Aventis and TEVA, none related to this manuscript. Elena K. Enax-Krumova is member of the German Research Network on Neuropathic pain e.V. (BMBF, grants 01EM0107 & 01EM0502), members of the European Collaboration, which has received support from the Innovative Medicines Initiative Joint Undertaking, under grant agreement no 11507, resources of which are composed of financial contribution from the European Union’s Seventh Framework Programme (FP7/2007-2013) and EFPIA companies (AstraZeneca, Pfizer, Esteve, UCB-Pharma, Sanofi-Aventis, Grünenthal, Eli Lilly und Boehringer Ingelheim) inkind contribution, was supported by intramural funding of the Ruhr University Bochum (FoRUM: grant number K046-10, Heinemann Award 2013) and has received a travel grant from Mundipharma GmbH and Bayer Vital GmbH, speaker fees from Grünenthal GmbH and Pfizer GmbH. Christoph Maier has received honoraria for speaking and advisory board membership from Gruenenthal, MSD, Köhler Chemie, Mundipharma, Pfizer, and Wyeth. Martin Tegenthoff has received speaker honoraria from Pfizer, Novartis and Mundipharma. He also acknowledges a grant support from Genzyme, not related to this manuscript. Tobias Schmidt-Wilcke received consulting fees from Daiichi Sankyo. Min-Suk Yoon has received speaker honoraria from CSL Behring and Grifols, a scientific grant from CSL Behring, none related to this manuscript.