Background Long-term support of stroke patients living at home is often delivered by family caregivers (FC). We identified characteristics of stroke patients being associated with receiving care by a FC 3-months (3 M) after stroke, assessed positive and negative experiences and individual burden of FC caring for stroke patients and determined factors associated with caregiving experiences and burden of FC 3 M after stroke. Methods Data were collected within TRANSIT-Stroke, a regional telemedical stroke-network comprising 12 hospitals in Germany. Patients with stroke/TIA providing informed consent were followed up 3 M after the index event. The postal patient-questionnaire was accompanied by an anonymous questionnaire for FC comprising information on positive and negative experiences of FC as well as on burden of caregiving operationalized by the Caregiver Reaction Assessment and a self-rated burden-scale, respectively. Multivariable logistic and linear regression analyses were performed. Results Between 01/2016 and 06/2019, 3532 patients provided baseline and 3 M-follow-up- data and 1044 FC responded to questionnaires regarding positive and negative caregiving experiences and caregiving burden. 74.4% of FC were older than 55 years, 70.1% were women and 67.5% were spouses. Older age, diabetes and lower Barthel-Index in patients were significantly associated with a higher probability of receiving care by a FC at 3 M. Positive experiences of FC comprised the importance (81.5%) and the privilege (70.0%) of caring for their relative; negative experiences of FC included financial difficulties associated with caregiving (20.4%). Median overall self-rated burden was 30 (IQR: 0–50; range 0–100). Older age of stroke patients was associated with a lower caregiver burden, whereas younger age of FC led to higher burden. More than half of the stroke patients in whom a FC questionnaire was completed did self-report that they are not being cared by a FC. This stroke patient group tended to be younger, more often male with less severe stroke and less comorbidities who lived more often with a partner. Conclusions The majority of caregivers wanted to care for their relatives but experienced burden at the same time. Elderly patients, patients with a lower Barthel Index at discharge and diabetes are at higher risk of needing care by a family caregiver. Trial registration The study was registered at “German Clinical Trial Register”: DRKS00011696. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00011696

The present cumulative dissertation summarizes three clinical studies, which examine subgroups of patients within the fibromyalgia syndrome (FMS). FMS entails chronic pain and associated symptoms, and its pathophysiology is incompletely understood (1). Previous studies show that there is a subgroup of patients with FMS with objective histological pathology of the small nerve fibers of the peripheral nervous system (PNS). Another subgroup of FMS patients does not show any signs of pathological changes of the small nerve fibers. The aim of this dissertation was to compare FMS patients with healthy controls, and these two FMS subgroups for differences in the central nervous system (CNS) in order to explore possible interactions between PNS and the CNS. Regarding the CNS, differences of FMS patients with healthy controls have already been found in studies with small sample sizes, but no subgroups have yet been identified. Another aim of this thesis was to test whether the subgroups show a different response to different classes of pain medication. The methods used in this thesis are structural and functional magnetic resonance imaging (MRI), magnetic resonance diffusion imaging and magnetic resonance spectroscopy. For the evaluation of clinical symptoms, we used standardized questionnaires. The subgroups with and without pathologies of the PNS were determined by skin biopsies of the right thigh and lower leg based on the intraepidermal nerve fiber density (IENFD) of the small nerve fibers. 1) In the first MRI study, 43 female patients with the diagnosis of FMS and 40 healthy control subjects, matched in age and body mass index, were examined with different MRI sequences. Cortical thickness was investigated by structural T1 imaging, white matter integrity by diffusion tensor imaging and functional connectivity within neuronal networks by functional resting state MRI. Compared to the controls, FMS patients had a lower cortical volume in bilateral frontotemporoparietal regions and the left insula, but a higher cortical volume in the left pericalcarine cortex. Compared to the subgroup without PNS pathology, the subgroup with PNS pathology had lower cortical volume in both pericalcarine cortices. Diffusion tensor imaging revealed an increased fractional anisotropy (FA) of FMS patients in corticospinal pathways such as the corona radiata, but also in regions of the limbic systems such as the fornix and cingulum. Subgroup comparison again revealed lower mean FA values of the posterior thalamic radiation and the posterior limb of the left internal capsule in the subgroup with PNS pathology. In the functional connectivity analysis FMS patients, compared to controls, showed a hypoconnectivity between the right median frontal gyrus and the posterior cerebellum and the right crus cerebellum, respectively. In the subgroup comparisons, the subgroup with PNS pathology showed a hyperconnectivity between both inferior frontal gyri, the right posterior parietal cortex and the right angular gyrus. In summary, these results show that differences in brain morphology and functional connectivity exist between FMS patients with and without PNS pathology. These differences were not associated with symptom duration or severity and, in some cases, have not yet been described in the context of FMS. The differences in brain morphology and connectivity between subgroups could also lead to a differential response to treatment with centrally acting drugs. Further imaging studies with FMS patients should take into account this heterogeneity of FMS patient cohorts. 2) Following the results from the first MRI study, drug therapies of FMS patients and their treatment response were compared between PNS subgroups. As there is no licensed drug for FMS in Europe, the German S3 guideline recommends amitriptyline, duloxetine and pregabalin for temporary use. In order to examine the current drug use in FMS patients in Germany on a cross-sectional basis, 156 patients with FMS were systematically interviewed. The drugs most frequently used to treat pain in FMS were non-steroidal anti-inflammatory drugs (NSAIDs) (28.9%), metamizole (15.4%) and amitriptyline (8.8%). Pain relief assessed by patients on a numerical rating scale from 0-10 averaged 2.2 points for NSAIDs, 2.0 for metamizole and 1.5 for amitriptyline. Drugs that were discontinued for lack of efficacy and not for side effects were acetaminophen (100%), flupirtine (91.7%), selective serotonin reuptake inhibitors (81.8%), NSAIDs (83.7%) and weak opioids (74.1%). Patients were divided into subgroups with and without PNS pathology as determined by skin biopsies. We found no differences in drug use and effect between the subgroups. Taken together, these results show that many FMS patients take medication that is not in accordance with the guidelines. The reduction of symptoms was best achieved with metamizole and NSAIDs. Further longitudinal studies on medication in FMS are necessary to obtain clearer treatment recommendations. 3) Derived from previous pharmacological and imaging studies (with smaller case numbers), there is a hypothesis in the FMS literature that hyperreactivity of the insular cortex may have an impact on FMS. The hyperreactivity seems to be due to an increased concentration of the excitatory neurotransmitter glutamate in the insular cortex of FMS patients. The hypothesis is supported by magnetic resonance spectroscopy studies with small number of cases, as well as results from pharmacological studies with glutamate-inhibiting medication. Studies from animal models have also shown that an artificially induced increase in glutamate in the insular cortex can lead to reduced skin innervation. Therefore, the aim of this study was to compare glutamate and GABA concentrations in the insular cortex of FMS patients with those of healthy controls using magnetic resonance imaging. There was no significant difference of both neurotransmitters between the groups. In addition, there was no correlation between the neurotransmitter concentrations and the severity of clinical symptoms. There were also no differences in neurotransmitter concentrations between the subgroups with and without PNS pathology. In conclusion, our study could not show any evidence of a correlation of glutamate and GABA concentrations with the symptoms of FMS or the pathogenesis of subgroups with PNS pathologies.

Background Despite of a multimodal approach, recurrences can hardly be prevented in glioblastoma. This may be in part due to so called glioma stem cells. However, there is no established marker to identify these stem cells. Methods Paired samples from glioma patients were analyzed by immunohistochemistry for expression of the following stem cell markers: CD133, Musashi, Nanog, Nestin, octamer-binding transcription factor 4 (Oct4), and sex determining region Y-box 2 (Sox2). In addition, the expression of osteopontin (OPN) was investigated. The relative number of positively stained cells was determined. By means of Kaplan–Meier analysis, a possible association with overall survival by marker expression was investigated. Results Sixty tissue samples from 30 patients (17 male, 13 female) were available for analysis. For Nestin, Musashi and OPN a significant increase was seen. There was also an increase (not significant) for CD133 and Oct4. Patients with mutated Isocitrate Dehydrogenase-1/2 (IDH-1/2) status had a reduced expression for CD133 and Nestin in their recurrent tumors. Significant correlations were seen for CD133 and Nanog between OPN in the primary and recurrent tumor and between CD133 and Nestin in recurrent tumors. By confocal imaging we could demonstrate a co-expression of CD133 and Nestin within recurrent glioma cells. Patients with high CD133 expression had a worse prognosis (22.6 vs 41.1 months, p = 0.013). A similar trend was seen for elevated Nestin levels (24.9 vs 41.1 months, p = 0.08). Conclusions Most of the evaluated markers showed an increased expression in their recurrent tumor. CD133 and Nestin were associated with survival and are candidate markers for further clinical investigation.

Autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A) is a steroid-responsive meningoencephalomyelitis, sometimes presenting with atypical clinical signs such as movement disorders or psychiatric and autonomic features. Beyond clinical presentation and imaging, diagnosis relies on detection of GFAP-antibodies (AB) in CSF. Using quantitative behavioral, serologic, and immunohistochemical analyses, we characterize two patients longitudinally over 18–24 months who presented with rapidly progressive neurocognitive deterioration in the context of GFAP-AB in CSF and unremarkable cranial MRI studies. Intensified immunotherapy was associated with clinical stabilization. The value of GFAP-AB screening in selected cases of rapidly progressive dementias is discussed.

Background Although Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the α-galactosidase A gene (GLA), women may develop severe symptoms. We investigated X-chromosomal inactivation patterns (XCI) as a potential determinant of symptom severity in FD women. Patients and Methods We included 95 women with mutations in GLA (n = 18 with variants of unknown pathogenicity) and 50 related men, and collected mouth epithelial cells, venous blood, and skin fibroblasts for XCI analysis using the methylation status of the androgen receptor gene. The mutated X-chromosome was identified by comparison of samples from relatives. Patients underwent genotype categorization and deep clinical phenotyping of symptom severity. Results 43/95 (45%) women carried mutations categorized as classic. The XCI pattern was skewed (i.e., ≥75:25% distribution) in 6/87 (7%) mouth epithelial cell samples, 31/88 (35%) blood samples, and 9/27 (33%) skin fibroblast samples. Clinical phenotype, α-galactosidase A (GAL) activity, and lyso-Gb3 levels did not show intergroup differences when stratified for X-chromosomal skewing and activity status of the mutated X-chromosome. Conclusions X-inactivation patterns alone do not reliably reflect the clinical phenotype of women with FD when investigated in biomaterial not directly affected by FD. However, while XCI patterns may vary between tissues, blood frequently shows skewing of XCI patterns.