Maintenance of neutralizing antibodies over ten months in convalescent SARS-CoV-2 afflicted patients.

Knowledge of the level and duration of protective immunity against SARS-CoV-2 after primary infection is of crucial importance for preventive approaches. Currently, there is a lack of evidence on the persistence of specific antibodies. We investigated the generation and maintenance of neutralizing antibodies of convalescent SARS-CoV-2-afflicted patients over a ten-month period post-primary infection using an immunofluorescence assay, a commercial chemiluminescent immunoassay and an in-house enzyme-linked neutralization assay. We present the successful application of an improved version of the plaque-reduction neutralization assay which can be analysed optometrically to simplify data interpretation. Based on the results of the enzyme-linked neutralization assay, neutralizing antibodies were maintained in 77.4% of convalescent individuals without relevant decay over ten months. Furthermore, a positive correlation between severity of infection and antibody titre was observed. In conclusion, SARS-CoV-2-afflicted individuals have been proven to be able to develop and maintain neutralizing antibodies over a period of ten months after primary infection. Findings suggest long-lasting presumably protective humoral immune responses after wild-type infection.

Smell and Taste Disorders in COVID-19 Patients: Objective Testing and Magnetic Resonance Imaging in Five Cases.

Smell and taste disorders are acknowledged as characteristic symptoms for SARS-CoV-2 infection by now. These symptoms have been linked to a neuroinvasive course of disease. In this study, we investigated five consecutive COVID-19 patients with a prolonged course of dysosmia and dysgeusia. Those with objectifiable alteration in taste or smell were subjected to MRI with contrast agent to investigate possible involvement of the central nervous system. We found dysosmia and dysgeusia to be mostly objectifiable, but no evidence for neuroinvasiveness could be detected by MRI in the late stage of the disease. Alterations in taste and smell could be objectified in most patients. Nevertheless, no evidence for a neuroinvasive potential could be identified by MRI, at least in the late stage of disease. We encourage medical professionals to conduct specialized examinations and MRIs in the acute stage of disease, which guarantees an optimum patient care.

Isoflurane Sedation in Patients Undergoing Venoarterial Extracorporeal Membrane Oxygenation Treatment for Cardiogenic Shock-An Observational Propensity-Matched Study.

The feasibility and hemodynamic effects of isoflurane sedation in cardiogenic shock in the presence of venoarterial extracorporeal membrane oxygenation treatment are currently unknown. DESIGN: Retrospective single-center study. SETTING: Cardiac ICU of Munich university hospital. PATIENTS/SUBJECTS: Cardiogenic shock patients with venoarterial extracorporeal membrane oxygenation treatment under sedation with volatile isoflurane between November 2018 and October 2019 have been enrolled in this study and were matched by propensity score in a 1:1 ratio with IV sedated patients treated between January 2013 and November 2018 from the cardiogenic shock registry of the university hospital of Munich. MEASUREMENTS AND MAIN RESULTS: Isoflurane sedation was used in 32 patients with cardiogenic shock and venoarterial extracorporeal membrane oxygenation treatment. The mean age of conventionally sedated patients was 58.4 ± 13.8 years and 56.3 ± 11.5 years for patients with isoflurane sedation (p = 0.51). Administration of isoflurane was associated with lower IV sedative drug use during venoarterial extracorporeal membrane oxygenation treatment (86% vs 32%; p = 0.01). Mean systolic arterial pressure was similar (94.3 ± 12.6 vs 92.9 ± 10.5 mm Hg; p = 0.65), but mean heart rate was significantly higher in the conventional sedation group, when compared with the isoflurane group (85.2 ± 20.5 vs 74.7 ± 15.0 beats/min; p = 0.02). Catecholamine doses, venoarterial extracorporeal membrane oxygenation blood and gas flow, ventilation time (304 ± 143 vs 398 ± 272 hr; p = 0.16), bleeding complications bleeding academic research consortium 3a or higher (59.3% vs 65.3%; p = 0.76), and 30-day mortality (59.2% vs 63.4%, p = 0.80) were similar in both groups. The overall sedation costs per patient were significantly lower in the conventional group, when compared with the isoflurane group (537 ± 624 vs 1280 ± 837 €; p < 0.001). CONCLUSIONS: Volatile sedation with isoflurane is feasible-albeit at higher costs-in patients with cardiogenic shock and venoarterial extracorporeal membrane oxygenation treatment and was not associated with higher catecholamine dosage or extracorporeal membrane oxygenation flow rate compared with IV sedation.