@article{PetzkeKloseWelschetal.2020, author = {Petzke, Frank and Klose, Petra and Welsch, Patrick and Sommer, Claudia and H{\"a}user, Winfried}, title = {Opioids for chronic low back pain: An updated systematic review and meta-analysis of efficacy, tolerability and safety in randomized placebo-controlled studies of at least 4 weeks of double-blind duration}, series = {European Journal of Pain}, volume = {24}, journal = {European Journal of Pain}, number = {3}, doi = {10.1002/ejp.1519}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218498}, pages = {497 -- 517}, year = {2020}, abstract = {Background and Objective This updated systematic review evaluated the efficacy, tolerability and safety of opioids compared to placebo in non-malignant chronic low back pain. Databases and Data Treatment Clinicaltrials.gov, CENTRAL, MEDLINE and PsycINFO were searched from October 2013 to May 2019. Randomized controlled trials comparing opioids with placebo and at least 4 weeks of double-blinded duration were analysed. Primary outcomes were pain relief of 50\% or greater, disability, tolerability and safety. Effects were summarized by a random effects model using risk differences or standardized mean differences. We added nine new studies with 2,980 participants for a total of 21 studies with 7,650 participants. Study duration ranged between 4 and 15 weeks. Studies with a parallel and cross-over design: Based on very low to low-quality evidence, opioids provided no clinically relevant pain relief of 50\% or greater, but a clinically relevant reduction of disability compared to placebo. Enriched enrolment randomized withdrawal (EERW) design: Based on very low to low-quality evidence, opioids provided a clinically relevant pain relief of 50\% or greater, but not a clinically relevant reduction of disability compared to placebo. There was no clinically relevant harm with regard to serious adverse events by opioids compared to placebo in studies with parallel/cross-over and EERW design. There was a relevant harm with regard to drop out rates due to adverse events in studies with parallel/cross-over, but not in studies with EERW design. Conclusions Opioids may provide a safe and clinically relevant pain relief for 4-15 weeks in highly selected patients. Significance Within the context of randomized controlled trials of 4-15 weeks, opioids provided a clinically relevant pain relief of 30\% or greater and a clinically relevant reduction of disability compared to placebo in non-malignant chronic low back pain. Number needed to treat for an additional drop out due to side effects was 11 (95\% confidence interval: 6-33). Assessment of abuse and addiction was incomplete. The frequency of serious adverse events including deaths did not differ from placebo.}, language = {en} } @article{SommerKloseWelschetal.2020, author = {Sommer, Claudia and Klose, Petra and Welsch, Patrick and Petzke, Frank and H{\"a}user, Winfried}, title = {Opioids for chronic non-cancer neuropathic pain. An updated systematic review and meta-analysis of efficacy, tolerability and safety in randomized placebo-controlled studies of at least 4 weeks duration}, series = {European Journal of Pain}, volume = {24}, journal = {European Journal of Pain}, number = {1}, doi = {10.1002/ejp.1494}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218487}, pages = {3 -- 18}, year = {2020}, abstract = {Background and Objective This updated systematic review evaluated the efficacy, tolerability and safety of opioids compared to placebo in chronic non-cancer neuropathic pain. Databases and Data Treatment Clinicaltrials.gov, CENTRAL, PubMed and PsycINFO were searched from October 2013 to June 2019. Randomized controlled trials comparing opioids with placebo and at least 4 weeks double-blinded duration were analysed. Primary outcomes were pain relief of 50\% or greater, disability, tolerability and safety. Effects were summarized by a random effects model using risk differences (RD) or standardized mean differences (SMD). We added four new studies with 662 participants for a total of 16 included studies with 2,199 participants. Study duration ranged between 4 and 12 weeks. Studies with a parallel and cross-over design: Based on low to moderate quality evidence, opioids (buprenorphine, hydromorphone, morphine, oxycodone, tramadol) provided a clinically relevant pain relief of 50\% or greater and reduction of disability compared to placebo. There was no clinically relevant harm with regards to the drop out rate due to adverse and serious adverse events by opioids compared to placebo. Enriched enrolment randomized withdrawal design: Based on low to moderate quality evidence, tapentadol provided a clinically relevant pain relief of 50\% or greater and reduction of disability compared to placebo in diabetic polyneuropathy. There was no clinically relevant harm with regards to the drop out rate due to adverse and serious adverse events by tapentadol compared to placebo. Conclusions Some opioids provided a short-term substantial pain relief in highly selected patients in some neuropathic pain syndromes. Significance Some opioids (buprenorphine, morphine, oxycodone, tramadol, tapentadol) provide substantial pain relief compared to placebo in postherpetic neuralgia and peripheral neuropathies of different aetiologies for 4-12 weeks. There is insufficient evidence to support or refute the suggestion that these drugs are effective in other neuropathic pain conditions. The safety of opioids with regards to abuse and deaths in the studies analysed cannot be extrapolated to routine clinical care.}, language = {en} } @article{RauschenbergervonWardenburgSchaeferetal.2020, author = {Rauschenberger, Vera and von Wardenburg, Niels and Schaefer, Natascha and Ogino, Kazutoyo and Hirata, Hiromi and Lillesaar, Christina and Kluck, Christoph J. and Meinck, Hans-Michael and Borrmann, Marc and Weishaupt, Andreas and Doppler, Kathrin and Wickel, Jonathan and Geis, Christian and Sommer, Claudia and Villmann, Carmen}, title = {Glycine Receptor Autoantibodies Impair Receptor Function and Induce Motor Dysfunction}, series = {Annals of Neurology}, volume = {88}, journal = {Annals of Neurology}, number = {3}, doi = {10.1002/ana.25832}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-216005}, pages = {544 -- 561}, year = {2020}, abstract = {Objective Impairment of glycinergic neurotransmission leads to complex movement and behavioral disorders. Patients harboring glycine receptor autoantibodies suffer from stiff-person syndrome or its severe variant progressive encephalomyelitis with rigidity and myoclonus. Enhanced receptor internalization was proposed as the common molecular mechanism upon autoantibody binding. Although functional impairment of glycine receptors following autoantibody binding has recently been investigated, it is still incompletely understood. Methods A cell-based assay was used for positive sample evaluation. Glycine receptor function was assessed by electrophysiological recordings and radioligand binding assays. The in vivo passive transfer of patient autoantibodies was done using the zebrafish animal model. Results Glycine receptor function as assessed by glycine dose-response curves showed significantly decreased glycine potency in the presence of patient sera. Upon binding of autoantibodies from 2 patients, a decreased fraction of desensitized receptors was observed, whereas closing of the ion channel remained fast. The glycine receptor N-terminal residues \(^{29}\)A to \(^{62}\)G were mapped as a common epitope of glycine receptor autoantibodies. An in vivo transfer into the zebrafish animal model generated a phenotype with disturbed escape behavior accompanied by a reduced number of glycine receptor clusters in the spinal cord of affected animals. Interpretation Autoantibodies against the extracellular domain mediate alterations of glycine receptor physiology. Moreover, our in vivo data demonstrate that the autoantibodies are a direct cause of the disease, because the transfer of human glycine receptor autoantibodies to zebrafish larvae generated impaired escape behavior in the animal model compatible with abnormal startle response in stiff-person syndrome or progressive encephalitis with rigidity and myoclonus patients.}, language = {en} } @article{JovanovicKlassenHeuschmannetal.2020, author = {Jovanovic, Ana and Klassen, Philipp and Heuschmann, Peter and Sommer, Claudia and Roberts, Mark and {\"U}{\c{c}}eyler, Nurcan}, title = {English version of the self-administered Fabry Pain Questionnaire for adult patients}, series = {Orphanet Journal of Rare Diseases}, volume = {15}, journal = {Orphanet Journal of Rare Diseases}, doi = {10.1186/s13023-020-01580-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230298}, year = {2020}, abstract = {Background Pain is an early symptom of Fabry disease (FD) and is characterized by a unique phenotype with mainly episodic acral and triggerable burning pain. Recently, we designed and validated the first pain questionnaire for adult FD patients in an interview and a self-administered version in German: the Wurzburg Fabry Pain Questionnaire (FPQ). We now report the validation of the English version of the self-administered FPQ (enFPQ). Methods After two forward-backward translations of the FPQ by native German and native English speakers, the enFPQ was applied at The Mark Holland Metabolic Unit, Manchester, UK for validation. Consecutive patients with genetically ascertained FD and current or previous FD pain underwent a face-to-face interview using the enFPQ. Two weeks later, patients filled in the self-administered enFPQ at home. The agreement between entries collected by supervised administration and self-administration of the enFPQ was assessed via Gwet's AC1-statistics (AC1) for nominal-scaled scores and intraclass correlation coefficient (ICC) for interval-scaled elements. Results Eighty-three FD patients underwent the face-to-face interview and 54 patients sent back a completed self-administered version of the enFPQ 2 weeks later. We found high agreement with a mean AC1-statistics of 0.725 for 55 items, and very high agreement with a mean ICC of 0.811 for 9 items. Conclusions We provide the validated English version of the FPQ for self-administration in adult FD patients. The enFPQ collects detailed information on the individual FD pain phenotype and thus builds a solid basis for better pain classification and treatment in patients with FD.}, language = {en} } @article{AppeltshauserBrunderHeiniusetal.2020, author = {Appeltshauser, Luise and Brunder, Anna-Michelle and Heinius, Annika and K{\"o}rtv{\´e}lyessy, Peter and Wandinger, Klaus-Peter and Junker, Ralf and Villmann, Carmen and Sommer, Claudia and Leypoldt, Frank and Doppler, Kathrin}, title = {Antiparanodal antibodies and IgG subclasses in acute autoimmune neuropathy}, series = {Neurology: Neuroimmunology \& Neuroinflammation}, volume = {7}, journal = {Neurology: Neuroimmunology \& Neuroinflammation}, number = {5}, doi = {10.1212/NXI.0000000000000817}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230079}, year = {2020}, abstract = {Objective To determine whether IgG subclasses of antiparanodal autoantibodies are related to disease course and treatment response in acute- to subacute-onset neuropathies, we retrospectively screened 161 baseline serum/CSF samples and 66 follow-up serum/CSF samples. Methods We used ELISA and immunofluorescence assays to detect antiparanodal IgG and their subclasses and titers in serum/CSF of patients with Guillain-Barre syndrome (GBS), recurrent GBS (R-GBS), Miller-Fisher syndrome, and acute- to subacute-onset chronic inflammatory demyelinating polyradiculoneuropathy (A-CIDP). We evaluated clinical data retrospectively. Results We detected antiparanodal autoantibodies with a prevalence of 4.3\% (7/161), more often in A-CIDP (4/23, 17.4\%) compared with GBS (3/114, 2.6\%). Longitudinal subclass analysis in the patients with GBS revealed IgG2/3 autoantibodies against Caspr-1 and against anti-contactin-1/Caspr-1, which disappeared at remission. At disease onset, patients with A-CIDP had IgG2/3 anti-Caspr-1 and anti-contactin-1/Caspr-1 or IgG4 anti-contactin-1 antibodies, IgG3 being associated with good response to IV immunoglobulins (IVIg). In the chronic phase of disease, IgG subclass of one patient with A-CIDP switched from IgG3 to IgG4. Conclusion Our data (1) confirm and extend previous observations that antiparanodal IgG2/3 but not IgG4 antibodies can occur in acute-onset neuropathies manifesting as monophasic GBS, (2) suggest association of IgG3 to a favorable response to IVIg, and (3) lend support to the hypothesis that in some patients, an IgG subclass switch from IgG3 to IgG4 may be the correlate of a secondary progressive or relapsing course following a GBS-like onset.}, language = {en} } @article{HartmannsbergerDopplerStauberetal.2020, author = {Hartmannsberger, Beate and Doppler, Kathrin and Stauber, Julia and Schlotter-Weigel, Beate and Young, Peter and Sereda, Michael W. and Sommer, Claudia}, title = {Intraepidermal nerve fiber density as biomarker in Charcot-Marie-Tooth disease 1A}, series = {Brain Communications}, volume = {2}, journal = {Brain Communications}, number = {1}, doi = {10.1093/braincomms/fcaa012}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229538}, year = {2020}, abstract = {Charcot-Marie-Tooth disease type 1A, caused by a duplication of the gene peripheral myelin protein 22 kDa, is the most frequent subtype of hereditary peripheral neuropathy with an estimated prevalence of 1:5000. Patients suffer from sensory deficits, muscle weakness and foot deformities. There is no treatment approved for this disease. Outcome measures in clinical trials were based mainly on clinical features but did not evaluate the actual nerve damage. In our case-control study, we aimed to provide objective and reproducible outcome measures for future clinical trials. We collected skin samples from 48 patients with Charcot-Marie-Tooth type 1A, 7 patients with chronic inflammatory demyelinating polyneuropathy, 16 patients with small fibre neuropathy and 45 healthy controls. To analyse skin innervation, 40-µm cryosections of glabrous skin taken from the lateral index finger were double-labelled by immunofluorescence. The disease severity of patients with Charcot-Marie-Tooth type 1A was assessed by the Charcot-Marie-Tooth neuropathy version 2 score, which ranged from 3 (mild) to 27 (severe) and correlated with age (P < 0.01, R = 0.4). Intraepidermal nerve fibre density was reduced in patients with Charcot-Marie-Tooth type 1A compared with the healthy control group (P < 0.01) and negatively correlated with disease severity (P < 0.05, R = -0.293). Meissner corpuscle (MC) density correlated negatively with age in patients with Charcot-Marie-Tooth type 1A (P < 0.01, R = -0.45) but not in healthy controls (P = 0.07, R = 0.28). The density of Merkel cells was reduced in patients with Charcot-Marie-Tooth type 1A compared with healthy controls (P < 0.05). Furthermore, in patients with Charcot-Marie-Tooth type 1A, the fraction of denervated Merkel cells was highly increased and correlated with age (P < 0.05, R = 0.37). Analysis of nodes of Ranvier revealed shortened paranodes and a reduced fraction of long nodes in patients compared with healthy controls (both P < 0.001). Langerhans cell density was increased in chronic inflammatory demyelinating polyneuropathy, but not different in Charcot-Marie-Tooth type 1A compared with healthy controls. Our data suggest that intraepidermal nerve fibre density might be used as an outcome measure in Charcot-Marie-Tooth type 1A disease, as it correlates with disease severity. The densities of Meissner corpuscles and Merkel cells might be an additional tool for the evaluation of the disease progression. Analysis of follow-up biopsies will clarify the effects of Charcot-Marie-Tooth type 1A disease progression on cutaneous innervation.}, language = {en} } @article{EvdokimovDinkelFranketal.2020, author = {Evdokimov, Dimitar and Dinkel, Philine and Frank, Johanna and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan}, title = {Characterization of dermal skin innervation in fibromyalgia syndrome}, series = {PLoS One}, volume = {15}, journal = {PLoS One}, number = {1}, doi = {10.1371/journal.pone.0227674}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229299}, year = {2020}, abstract = {Introduction We characterized dermal innervation in patients with fibromyalgia syndrome (FMS) as potential contribution to small fiber pathology. Methods Skin biopsies of the calf were collected (86 FMS patients, 35 healthy controls). Skin was immunoreacted with antibodies against protein gene product 9.5, calcitonine gene-related peptide, substance P, CD31, and neurofilament 200 for small fiber subtypes. We assessed two skin sections per patient; on each skin section, two dermal areas (150 x 700 mu m each) were investigated for dermal nerve fiber length (DNFL). Results In FMS patients we found reduced DNFL of fibers with vessel contact compared to healthy controls (p<0.05). There were no differences for the other nerve fiber subtypes. Discussion We found less dermal nerve fibers in contact with blood vessels in FMS patients than in controls. The pathophysiological relevance of this finding is unclear, but we suggest the possibility of a relationship with impaired thermal tolerance commonly reported by FMS patients.}, language = {en} } @article{UeceylerBuchholzKewenigetal.2020, author = {{\"U}{\c{c}}eyler, Nurcan and Buchholz, Hans-Georg and Kewenig, Susanne and Ament, Stephan-Johann and Birklein, Frank and Schreckenberger, Mathias and Sommer, Claudia}, title = {Cortical Binding Potential of Opioid Receptors in Patients With Fibromyalgia Syndrome and Reduced Systemic Interleukin-4 Levels - A Pilot Study}, series = {Frontiers in Neuroscience}, volume = {14}, journal = {Frontiers in Neuroscience}, issn = {1662-453X}, doi = {10.3389/fnins.2020.00512}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-204457}, year = {2020}, abstract = {Objective: We investigated cerebral opioid receptor binding potential in patients with fibromyalgia syndrome (FMS) using positron-emission-tomography (PET) and correlated our results with patients' systemic interleukin-4 (IL-4) gene expression. Methods: In this pilot study, seven FMS patients (1 man, 6 women) agreed to participate in experimental PET scans. All patients underwent neurological examination, were investigated with questionnaires for pain, depression, and FMS symptoms. Additionally, blood for IL-4 gene expression analysis was withdrawn at two time points with a median latency of 1.3 years. Patients were investigated in a PET scanner using the opioid receptor ligand F-18-fluoro-ethyl-diprenorphine ([18F]FEDPN) and results were compared with laboratory normative values. Results: Neurological examination was normal in all FMS patients. Reduced opioid receptor binding was found in mid cingulate cortex compared to healthy controls (p < 0.005). Interestingly, three patients with high systemic IL-4 gene expression had increased opioid receptor binding in the fronto-basal cortex compared to those with low IL-4 gene expression (p < 0.005). Conclusion: Our data give further evidence for a reduction in cortical opioid receptor availability in FMS patients as another potential central nervous system contributor to pain in FMS.}, language = {en} } @article{KlitschEvdokimovFranketal.2020, author = {Klitsch, Alexander and Evdokimov, Dimitar and Frank, Johanna and Thomas, Dominique and Saffer, Nadine and Meyer zu Altenschildesche, Caren and Sisignano, Marco and Kampik, Daniel and Malik, Rayaz A. and Sommer, Claudia and {\"U}{\c{c}}eyler, Nurcan}, title = {Reduced association between dendritic cells and corneal sub-basal nerve fibers in patients with fibromyalgia syndrome}, series = {Journal of the Peripheral Nervous System}, volume = {25}, journal = {Journal of the Peripheral Nervous System}, number = {1}, doi = {10.1111/jns.12360}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214150}, pages = {9-18}, year = {2020}, abstract = {In our study, we aimed at investigating corneal langerhans cells (LC) in patients with fibromyalgia syndrome (FMS) and small fiber neuropathy (SFN) as potential contributors to corneal small fiber pathology. We enrolled women with FMS (n = 134) and SFN (n = 41) who underwent neurological examination, neurophysiology, prostaglandin analysis in tear fluid, and corneal confocal microscopy (CCM). Data were compared with those of 60 age-matched female controls. After screening for dry eye disease, corneal LC were counted and sub-classified as dendritic (dLC) and non-dendritic (ndLC) cells with or without nerve fiber association. We further analyzed corneal nerve fiber density (CNFD), length (CNFL), and branch density (CNBD). Neurological examination indicated deficits of small fiber function in patients with SFN. Nerve conduction studies were normal in all participants. Dry eye disease was more prevalent in FMS (17\%) and SFN (28\%) patients than in controls (5\%). Tear fluid prostaglandin levels did not differ between FMS patients and controls. While corneal LC density in FMS and SFN patients was not different from controls, there were fewer dLC in association with nerve fibers in FMS and SFN patients than in controls (P < .01 each). Compared to controls, CNFL was lower in FMS and SFN patients (P < .05 each), CNFD was lower only in FMS patients (P < .05), and CNBD was lower only in SFN patients (P < .001). There was no difference in any CCM parameter between patients with and without dry eyes. Our data indicate changes in corneal innervation and LC distribution in FMS and SFN, potentially based on altered LC signaling.}, language = {en} }