Association of the neonatal Fc receptor promoter variable number of tandem repeat polymorphism with immunoglobulin response in patients with chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune disease with humoral and cellular autoimmunity causing demyelination of peripheral nerves, commonly treated with intravenous immunoglobulins (IVIg). The neonatal Fc receptor (FcRn), encoded by the FCGRT gene, prevents the degradation of immunoglobulin G (IgG) by recycling circulating IgG. A variable number of tandem repeat (VNTR) polymorphism in the promoter region of the FCGRT gene is associated with different expression levels of mRNA and protein. Thus, patients with genotypes associated with relatively low FcRn expression may show a poorer treatment response to IVIg due to increased IVIg degradation. METHODS: VNTR genotypes were analyzed in 144 patients with CIDP. Patients' clinical data, including neurological scores and treatment data, were collected as part of the Immune-Mediated Neuropathies Biobank registry. RESULTS: Most patients (n = 124, 86%) were VNTR 3/3 homozygotes, and 20 patients (14%) were VNTR 2/3 heterozygotes. Both VNTR 3/3 and VNTR 2/3 genotype groups showed no difference in clinical disability and immunoglobulin dosage. However, patients with a VNTR 2 allele were more likely to receive subcutaneous immunoglobulins (SCIg) than patients homozygous for the VNTR 3 allele (25% vs. 9.7%, p = 0.02) and were more likely to receive second-line therapy (75% vs. 54%, p = 0.05). CONCLUSIONS: The VNTR 2/3 genotype is associated with the administration of SCIg, possibly reflecting a greater benefit from SCIg due to more constant immunoglobulin levels without lower IVIg levels between the treatment circles. Also, the greater need for second-line treatment in VNTR 2/3 patients could be an indirect sign of a lower response to immunoglobulins.

The impact of the SARS-CoV-2-pandemic on patients with chronic inflammatory neuropathies: results from the German INHIBIT register.

INTRODUCTION: SARS-CoV-2 pandemic is especially compromising for patients with autoimmune diseases with or without immunomodulatory treatment. This study aimed to investigate the longitudinal changes in the health care of patients with immune-mediated neuropathies during the COVID-19 pandemic. METHODS: We performed a longitudinal study using questionnaires in a prospective cohort of patients with immune-mediated neuropathies at two timepoints of the pandemic: May-July 2021 and May-July 2022. RESULTS: The cohort consisted of 73 patients (55 male), mean age 62 years, 68 patients with CIDP, 5 with other immune neuropathies. In 2021, 19.2% of the patients reported a reduced number of physician-patient-contacts, while 13.7% reported this in 2022. Nevertheless, the overall health-care situation worsened from 2021 to 2022: 15.1% reported reduced overall healthcare in 2021, 26.0% in 2022. In 2021, 29.4% of patients reported absence of physio-/occupational therapy, while 34.4% reported this in 2022. Switching immunomodulatory treatment and stretching of treatment intervals occurred more often in 2022 (38.4%) than in 2021 (27.4%). 12 COVID-19-infections occurred overall, with typical only mild symptoms. The rate of fully vaccinated patients was 61.6% and 98.6% in May-July 2021 and 2022, respectively. Only minor side-effects after vaccination were reported. CONCLUSION: Despite mitigation of COVID-19 restrictions from 2021 to 2022, the health-care situation of patients worsened in this time. Reasons could be the international shortage of immunoglobulins during the pandemic and reduced physio/ergotherapy due to lingering regulatory restrictions. Vaccination rate was high in our cohort of patients compared to the general German population and CIDP did not seem to be a risk factor for severe SARS-CoV-2 infections.

Numerical simulation of an atmospheric pressure RF-driven plasma needle and heat transfer to adjacent human skin using COMSOL.

Plasma medicine is an emerging field where plasma physics is used for therapeutical applications. Temperature is an important factor to take into account with respect to the applications of plasma to biological systems. During the treatment, the tissue temperature could increase to critical values. In this work, a model is presented, which is capable of predicting the skin temperature during a treatment with a radio frequency driven plasma needle. The main gas was helium. To achieve this, a discharge model was coupled to a heat transfer and fluid flow model. The results provide maximum application times for different power depositions in order to avoid reaching critical skin temperatures.