@article{DirksFischerHaaseetal.2021,
  author    = {Dirks, Johannes and Fischer, Jonas and Haase, Gabriele and Holl-Wieden, Annette and Hofmann, Christine and Girschick, Hermann and Morbach, Henner},
  title     = {CD21\(^{lo/-}\)CD27\(^-\)IgM\(^-\) Double-Negative B Cells Accumulate in the Joints of Patients With Antinuclear Antibody-Positive Juvenile Idiopathic Arthritis},
  series = {Frontiers in Pediatrics},
  volume    = {9},
  journal   = {Frontiers in Pediatrics},
  issn      = {2296-2360},
  doi       = {10.3389/fped.2021.635815},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-236286},
  year      = {2021},
  abstract  = {Juvenile idiopathic arthritis (JIA) encompasses a heterogeneous group of diseases. The appearance of antinuclear antibodies (ANAs) in almost half of the patients suggests B cell dysregulation as a distinct pathomechanism in these patients. Additionally, ANAs were considered potential biomarkers encompassing a clinically homogenous subgroup of JIA patients. However, in ANA+ JIA patients, the site of dysregulated B cell activation as well as the B cell subsets involved in this process is still unknown. Hence, in this cross-sectional study, we aimed in an explorative approach at characterizing potential divergences in B cell differentiation in ANA+ JIA patients by assessing the distribution of peripheral blood (PB) and synovial fluid (SF) B cell subpopulations using flow cytometry. The frequency of transitional as well as switched-memory B cells was higher in PB of JIA patients than in healthy controls. There were no differences in the distribution of B cell subsets between ANA- and ANA+ patients in PB. However, the composition of SF B cells was different between ANA- and ANA+ patients with increased frequencies of CD21\(^{lo/-}\)CD27\(^-\)IgM\(^-\) "double negative" (DN) B cells in the latter. DN B cells might be a characteristic subset expanding in the joints of ANA+ JIA patients and are potentially involved in the antinuclear immune response in these patients. The results of our explorative study might foster further research dissecting the pathogenesis of ANA+ JIA patients.},
  language  = {en}
}
@article{vonLukowiczSchlegelHaerteletal.2021,
  author    = {von Lukowicz, Hannah and Schlegel, Paul-Gerhardt and H{\"a}rtel, Christoph and Morbach, Henner and Haubitz, Imme and Wiegering, Verena},
  title     = {ESPED survey on newly diagnosed immune thrombocytopenia in childhood: how much treatment do we give?},
  series = {Molecular and Cellular Pediatrics},
  volume    = {8},
  journal   = {Molecular and Cellular Pediatrics},
  doi       = {10.1186/s40348-021-00121-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-261832},
  year      = {2021},
  abstract  = {Background Immune thrombocytopenia (ITP) is an autoimmune disease associated with isolated thrombocytopenia, which is caused by an imbalance between platelet production and platelet destruction. Petechial and mucous membrane hemorrhages are characteristic of ITP, but life-threatening bleeding rarely occurs. Depending on the bleeding symptoms, ITP can be treated with glucocorticoids (GC), intravenous immunoglobulins (IVIG), or in severe cases, platelet transfusions. Mild bleeding does not necessarily require therapy. Using the German Surveillance Unit for rare Pediatric Diseases (ESPED) we conducted a prospective survey on ITP patients in all German Children's Hospitals between September 2018 and August 2019. We collected data on ITP, including the clinical course, therapy implementation recommendations (according to the Association of German Scientific Medical Societies guidelines), outcome, and influence of treatment regimens depending on the treating physician´s experience with ITP patients. Results Of the 287 recorded cases of children with ITP, 268 questionnaires were sent to the authors. Two hundred seventeen of the questionnaires fulfilled the inclusion criteria. ITP affected boys and girls similarly, and the median age of manifestation was 3.5 years. The main reasons for hospitalization were thrombocytopenia, bleeding signs, hematomas, and/or petechiae. Bleeding scores were ≤ 3 in 96\% of children, which corresponded to a low-to-moderately low risk of bleeding. No life-threatening bleeding was documented. The most common therapies were IVIG (n = 59), GC (n = 33), or a combination of these (n = 17). Blood products (i.e., red blood cells, platelet concentrate, and fresh frozen plasma) were given to 13 patients. Compared to the established guidelines, 67 patients were over-treated, and 2 patients were under-treated. Conclusions Adherence to German ITP treatment guidelines is currently limited. To improve patient safety and medical care, better medical training and dissemination of the guidelines are required in line with targeted analyses of patients with serious bleeding events to identify potential risk constellations.},
  language  = {en}
}