[Rare diseases in anesthesia : Knowledge mining and core points of perioperative anesthesiological care]

Due to refined and new diagnostic possibilities and improved medical care, in the future anesthesiologists will be more frequently confronted with patients suffering from rare diseases. As the physicians providing perioperative care often have little or no experience with the diseases of such patients, the access to high-quality specific literature is essential. In this respect they must be able to assess and classify the quality of the information which is predominantly available online, especially as when evidence-based knowledge is available, it is only available to a very limited extent. Patients with rare diseases mostly present with recurring problem constellations. A systematic assignment to the most important problem areas (airway, circulation, metabolism, etc.) as well as a structured and interdisciplinary approach are decisive for a successful perioperative treatment of these patients. Due to low prevalence, lack of personal experience and lack of evidence-based data, anesthesia in patients with SE is an absolute challenge, especially in time-critical situations.

[Diagnosis and Treatment of IgA Nephropathy-2023]

Immunoglobulin A nephropathy (IgAN) is the most common glomerulonephritis. It leads to end-stage kidney disease in about a third of the patients within 10 to 20 years. The pathogenesis of IgAN is incompletely understood. It is believed that a dysregulation of the mucosal immune system leads to undergalactosylation of IgA, followed by formation of IgG autoantibodies against undergalactosylated IgA, circulation of these IgG-IgA immune complexes, deposition of the immune complexes in the mesangium, ultimately resulting in glomerular inflammation. IgAN can occasionally be triggered by other diseases, these secondary causes of IgAN should be identified or ruled out (chronic inflammatory bowel disease, infections, tumors, rheumatic diseases). Characteristic findings of IgAN of variable extent are a nephritic urinary sediment (erythrocytes, acanthocytes, erythrocyte casts), proteinuria, impaired renal function, arterial hypertension, or intermittent painless macrohematuria, especially during infections of the upper respiratory tract. However, the diagnosis of IgAN can only be made by a kidney biopsy. A histological classification (MEST‑C score) should always be reported to be able to estimate the prognosis. The most important therapeutic measure is an optimization of the supportive therapy, which includes, among other things, a consistent control of the blood pressure, an inhibition of the RAS, and the administration of an SGLT2 inhibitor. A systemic immunosuppressive therapy with corticosteroids is discussed controversially, should be used restrictively and only administered after an individual benefit-risk assessment under certain conditions that speak for a progressive IgAN. New promising therapeutics are enteral Budesonide or the dual angiotensin-II-receptor- and endothelin-receptor-antagonist Sparsentan. Rapidly progressive IgAN should be treated with corticosteroids and cyclophosphamide like ANCA-associated vasculitis.

Humoral and Cellular Immune Response After a 3-Dose Heterologous SARS-CoV-2 Vaccination Using the mRNA-BNT162b2 and Viral Vector Ad26COVS1 Vaccine in Hemodialysis Patients

Background

Due to the waning humoral response after a two-dose SARS-CoV-2 mRNA vaccination, a third booster was recommended in hemodialyis patients. Data on a heterologous mRNA-vector regimen, which might improve immunogenicity, are very limited.

Methods

In this observational study 36 chronic hemodialysis patients (mean (SD) age 66.9 (15.9) years, 33.3% females) were followed up for 13 months. All patients were vaccinated twice using the mRNA-BNT162b2 vaccine, followed by a 3^rd dose of the vector vaccine Ad26COVS1 eight months later. We assessed the humoral response by quantifying the anti-SARS-CoV-2 spike IgG antibody and neutralizing antibody concentrations. The cellular immune response was evaluated via SARS-CoV-2 spike protein-specific interferon-γ release assay.

Results

The seroconversion rate was 47.2%, 100%, 69.4% and 100% one month after the 1^st dose, one and six months after the 2^nd dose and four months after the heterologous 3^rd dose. The median (Q1, Q3) anti-SARS-CoV-2 spike IgG concentrations at the same time were 28.7 (13.2, 69.4) BAU/ml, 1130.0 (594.5, 1735.0) BAU/ml, 89.7 (26.4, 203.8) BAU/ml, and 2080.0 (1062.5, 2080.0) BAU/ml. The percentage of patients with neutralizing antibodies was 58.3% after the 2^nd dose and improved to 100% after the 3^rd dose (P <0.001). A positive T-cell response was found in 50% of patients after the 3^rd dose.

Conclusions

A third heterologous booster dose helped to sustain humoral immunity in almost all hemodialysis patients and induced a significant T-cellular response in half of them. Stimulating the immune response against SARS-CoV-2 by two different vaccine platforms seems to be a promising approach.

Preparation and evaluation of reduction-responsive micelles based on disulfide-linked chondroitin sulfate A-tocopherol succinate for controlled antitumour drug release

OBJECTIVES

The study was to construct reduction-responsive chondroitin sulfate A (CSA)-conjugated TOS (CST) micelles with disulfide bond linkage, which was used for controlled doxorubicin (DOX) release and improved drug efficacy in vivo.

METHODS

CST and non-responsive CSA-conjugated TOS (CAT) were synthesized, and the chemical structure was confirmed by Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, fluorescence spectrophotometer and dynamic light scattering. Antitumour drug DOX was physically encapsulated into CST and CSA by dialysis method. Cell uptake of DOX-based formulations was investigated by confocal laser scanning microscopy. In vitro cytotoxicity was studied in A549 and AGS cells. Furthermore, antitumour activity was evaluated in A549-bearing mice.

KEY FINDINGS

CST and CAT can form self-assembled micelles, and have low value of critical micelle concentration. Notably, DOX-containing CST (D-CST) micelles demonstrated reduction-triggered drug release in glutathione-containing media. Further, reduction-responsive uptake of D-CST was observed in A549 cells. In addition, D-CST induced stronger cytotoxicity (P < 0.05) than DOX-loaded CAT (D-CAT) against A549 and AGS cells. Moreover, D-CST exhibited significantly stronger antitumour activity in A549-bearing nude mice than doxorubicin hydrochloride and D-CAT.

CONCLUSIONS

The reduction-responsive CST micelles enhanced the DOX effect at tumour site and controlled drug release.

The Safety and Immunogenicity of the mRNA-BNT162b2 SARS-CoV-2 Vaccine in Hemodialysis Patients

Background

Hemodialysis patients are at high risk for severe COVID-19. SARS-CoV-2 vaccination related safety and immunogenicity data in these patients are rare.

Methods

In this observational study SARS-CoV-2-seronegative hemodialysis patients were vaccinated with two doses of the Pfizer/BioNTech mRNA-BNT162b2 vaccine (COMIRNATY^® 30 µg) and followed for 90 days. Local and systemic side effects were assessed at every dialysis session during the first post-vaccination week after the first and second vaccine dose. Immunogenicity was determined four weeks after vaccination by quantifying anti-SARS-CoV-2 spike protein IgG antibodies (LIAISON^® SARS-CoV-2-TrimericS IgG chemiluminescent immunoassay) expressed in binding activity units per milliliter (BAU/mL) adapted to the WHO International standard.

Results

Fifty patients (32% women, 68% men) with a mean (SD) age of 67.6 (14.8) years were included. Mild local reactions occurred in 38% after the first injection, and in 29.2% with mild, in 2.1% with moderate and in 2.1% with severe degree after the second injection. Systemic reactive events occurred less often, with diarrhea (4% mild, 4% moderate) and fatigue (8% mild) being the most frequent ones. After the first injection 42% of the patients developed a positive response using the assay specific cut-off value of 33.8 binding activity units per milliliter (BAU/mL) with a median (Q1, Q3) anti-SARS-CoV-2 spike IgG concentration of 20.0 (11.7, 51.0) BAU/mL. After the second injection the percentage of seropositive patients increased to 97.9% with an anti-SARS-CoV-2 spike IgG concentration of 1075 (290.8, 1735) BAU/mL. Higher age and immunosuppression were associated with lower, calcitriol treatment and prior seroconversion to hepatitis B vaccination with significantly higher antibody concentration.

Conclusions

The mRNA-BNT162b2 SARS-CoV-2 vaccine appears to be safe and well-tolerated and shows a high immunogenicity in hemodialysis patients.

[Intracranial hemorrhage secondary to vitamin K deficiency in an infant despite oral vitamin K prophylaxis : Also a challenge for the anesthesiologist]

This article presents the case of a 6-week-old infant who, despite oral vitamin K prophylaxis and otherwise normal developmental progress, suffered a severe intracerebral and subdural hemorrhage, which required surgical evacuation. The interdisciplinary approach is described with emphasis on the management of hemostasis. Furthermore, the clinical picture of intracranial bleeding due to vitamin K deficiency, which is nowadays rare in the Western World, is described in the anesthesiology literature for the first time. The usual recommendations regarding prophylaxis as well as certain risk factors are presented.

[Transverse myelopathy as a complication following long-term intrathecal application of morphine in chronic back pain]

Serious neurological complications following long-term intrathecal application of opiates have seldom been published. This report describes complications which developed three months after reimplantation of a spinal catheter for pain therapy. The symptoms which occurred were paraparesis of the legs with sensory loss and urinary retention. A regression of these symptoms occurred only after explantation of the spinal catheter-pump-system. Possible reasons and consequences are discussed.

Proteoglycan distribution pattern during aging in the nematode Caenorhabditis elegans: an ultrastructural histochemical study

Glycosaminoglycans are important constituents of the extracellular matrix of vertebrates, where distinct changes in their distribution pattern occur during aging. However, little is known about their changes in the nematode Caenorhabditis elegans, which ages extremely rapidly compared to mammals. The presence of glycosaminoglycans was analysed in cross-sections of all organs of the nematode, in three different age groups (60, 144, 228 h), using the electron-dense dye Cuprolinic Blue in conjunction with the critical electrolyte concentration method and specific glycosaminoglycan degrading enzymes. The nematodes (strain DH 26) were grown at 25.5 degrees C. The results indicate the presence of an organ-specific distribution pattern. Chondroitin-4-sulphate and/or chondroitin-6-sulphate are present in the epicuticula. Chondroitin-4-sulphate and/or chondroitin-6-sulphate and dermatan sulphate are detected in the mesocuticula. If stained by conventional methods the mesocuticula shows an empty fissure, which is filled by chondroitin sulphates and dermatan sulphate as shown by Cuprolinic Blue staining and enzymes. Heparan sulphate is found in the terminal web of intestinal cells while dermatan sulphate is revealed in the central cores of microvilli. An unknown polyanion staining at high electrolyte concentrations is observed in the gonads. Age-related changes do not impair the composition of the glycosaminoglycan fraction. In conclusion an unexpected highly differentiated pattern of glycosaminoglycans with high stability during aging exists.