@article{BreyerGruenerKleinetal.2024, author = {Breyer, Maximilian and Gr{\"u}ner, Julia and Klein, Alexandra and Finke, Laura and Klug, Katharina and Sauer, Markus and {\"U}{\c{c}}eyler, Nurcan}, title = {\(In\) \(vitro\) characterization of cells derived from a patient with the GLA variant c.376A>G (p.S126G) highlights a non-pathogenic role in Fabry disease}, series = {Molecular Genetics and Metabolism Reports}, volume = {38}, journal = {Molecular Genetics and Metabolism Reports}, issn = {22144269}, doi = {10.1016/j.ymgmr.2023.101029}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350295}, year = {2024}, abstract = {Highlights • The GLA variant S126G is not associated with Fabry symptoms in the presented case • S126G has no effect on α-GAL A activity or Gb3 levels in this patient • S126G sensory neurons show no electrophysiological abnormalities Abstract Fabry disease (FD) is a life-limiting disorder characterized by intracellular globotriaosylceramide (Gb3) accumulations. The underlying α-galactosidase A (α-GAL A) deficiency is caused by variants in the gene GLA. Variants of unknown significance (VUS) are frequently found in GLA and challenge clinical management. Here, we investigated a 49-year old man with cryptogenic lacunar cerebral stroke and the chance finding of the VUS S126G, who was sent to our center for diagnosis and initiation of a costly and life-long FD-specific treatment. We combined clinical examination with in vitro investigations of dermal fibroblasts (HDF), induced pluripotent stem cells (iPSC), and iPSC-derived sensory neurons. We analyzed α-GAL A activity in iPSC, Gb3 accumulation in all three cell types, and action potential firing in sensory neurons. Neurological examination and small nerve fiber assessment was normal except for reduced distal skin innervation. S126G iPSC showed normal α-GAL A activity compared to controls and no Gb3 deposits were found in all three cell types. Baseline electrophysiological characteristics of S126G neurons showed no difference compared to healthy controls as investigated by patch-clamp recordings. We pioneer multi-level cellular characterization of the VUS S126G using three cell types derived from a patient and provide further evidence for the benign nature of S126G in GLA, which is of great importance in the management of such cases in clinical practice.}, language = {en} } @article{JaenschEvdokimovEgenolfetal.2024, author = {J{\"a}nsch, Sarah and Evdokimov, Dimitar and Egenolf, Nadine and Meyer zu Altenschildesche, Caren and Kreß, Luisa and {\"U}{\c{c}}eyler, Nurcan}, title = {Distinguishing fibromyalgia syndrome from small fiber neuropathy: a clinical guide}, series = {Pain Reports}, volume = {9}, journal = {Pain Reports}, number = {1}, doi = {10.1097/PR9.0000000000001136}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-350306}, year = {2024}, abstract = {Introduction: Fibromyalgia syndrome (FMS) and small fiber neuropathy (SFN) are distinct pain conditions that share commonalities and may be challenging as for differential diagnosis. Objective: To comprehensively investigate clinical characteristics of women with FMS and SFN to determine clinically applicable parameters for differentiation. Methods: We retrospectively analyzed medical records of 158 women with FMS and 53 with SFN focusing on pain-specific medical and family history, accompanying symptoms, additional diseases, and treatment. We investigated data obtained using standardized pain, depression, and anxiety questionnaires. We further analyzed test results and findings obtained in standardized small fiber tests. Results: FMS patients were on average ten years younger at symptom onset, described higher pain intensities requiring frequent change of pharmaceutics, and reported generalized pain compared to SFN. Pain in FMS was accompanied by irritable bowel or sleep disturbances, and in SFN by paresthesias, numbness, and impaired glucose metabolism (P < 0.01 each). Family history was informative for chronic pain and affective disorders in FMS (P < 0.001) and for neurological disorders in SFN patients (P < 0.001). Small fiber pathology in terms of skin denervation and/or thermal sensory threshold elevation was present in 110/158 (69.7 \%) FMS patients and 39/53 (73.6 \%) SFN patients. FMS patients mainly showed proximally reduced skin innervation and higher corneal nerve branch densities (p<0.001) whereas SFN patients were characterized by reduced cold detection and prolonged electrical A-delta conduction latencies (P < 0.05). Conclusions: Our data show that FMS and SFN differ substantially. Detailed pain, drug and family history, investigating blood glucose metabolism, and applying differential small fiber tests may help to improve diagnostic differentiation and targeted therapy.}, language = {en} }