Induction of hypoxia-inducible-factor-1α (HIF-1α) pathway and HIF-target genes allow adaptation to hypoxia and are associated with reduced incidence of acute mountain sickness (AMS). Little is known about HIF-pathways in conjunction with inflammation or exercise stimuli under acute hypobaric hypoxia in non-acclimatized individuals. We therefore tested the hypotheses that (1) both hypoxic and inflammatory stimuli induce hypoxic-inflammatory signaling pathways in vitro, (2) similar results are seen in vivo under hypobaric hypoxia, and (3) induction of HIF-dependent genes is associated with AMS in 11 volunteers. In vitro, peripheral blood mononuclear cells (PBMCs) were incubated under hypoxic (10%/5% O2) or inflammatory (CD3/CD28) conditions. In vivo, Interleukin 1β (IL-1β), C-X-C Chemokine receptor type 4 (CXCR-4), and C-C Chemokine receptor type 2 (CCR-2) mRNA expression, cytokines and receptors were analyzed under normoxia (520 m above sea level (a.s.l.)), hypobaric hypoxia (3883 m a.s.l.) before/after exercise, and after 24 h under hypobaric hypoxia. In vitro, isolated hypoxic (p = 0.004) or inflammatory (p = 0.006) stimuli induced IL-1β mRNA expression. CCR-2 mRNA expression increased under hypoxia (p = 0.005); CXCR-4 mRNA expression remained unchanged. In vivo, cytokines, receptors, and IL-1β, CCR-2 and CXCR-4 mRNA expression increased under hypobaric hypoxia after 24 h (all p ≤ 0.05). Of note, proinflammatory IL-1β and CXCR-4 mRNA expression changes were associated with symptoms of AMS. Thus, hypoxic-inflammatory pathways are differentially regulated, as combined hypoxic and exercise stimulus was stronger in vivo than isolated hypoxic or inflammatory stimulation in vitro.
ObjectiveNormobaric (NH) and hypobaric hypoxia (HH) are associated with acute mountain sickness (AMS) and cognitive dysfunction. Only few variables, like heart-rate-variability, are correlated with AMS. However, prediction of AMS remains difficult. We therefore designed an expedition-study with healthy volunteers in NH/HH to investigate additional non-invasive hemodynamic variables associated with AMS.MethodsEleven healthy subjects were examined in NH (FiO2 13.1%; equivalent of 3.883 m a.s.l; duration 4 h) and HH (3.883 m a.s.l.; duration 24 h) before and after an exercise of 120 min. Changes in parameters of electrical cardiometry (cardiac index (CI), left-ventricular ejection time (LVET), stroke volume (SV), index of contractility (ICON)), near-infrared spectroscopy (cerebral oxygenation, rScO2), Lake-Louise-Score (LLS) and cognitive function tests were assessed. One-Way-ANOVA, Wilcoxon matched-pairs test, Spearman’s-correlation-analysis and Student’s t-test were performed.ResultsHH increased heart rate (HR), mean arterial pressure (MAP) and CI and decreased LVET, SV and ICON, whereas NH increased HR and decreased LVET. In both NH and HH cerebral oxygenation decreased and LLS increased significantly. After 24 h in HH, 6 of 11 subjects (54.6%) developed AMS. LLS remained increased until 24 h in HH, whereas cognitive function remained unaltered. In HH, HR and LLS were inversely correlated (r = − 0.692; p < 0.05). More importantly, the rScO2-decrease after exercise in NH significantly correlated with LLS after 24 h in HH (r = − 0.971; p < 0.01) and rScO2 correlated significantly with HR (r = 0.802; p < 0.01), CI (r = 0.682; p < 0.05) and SV (r = 0.709; p < 0.05) after exercise in HH.ConclusionsBoth acute NH and HH altered hemodynamic and cerebral oxygenation and induced AMS. Subjects, who adapted their CI had higher rScO2 and lower LLS. Furthermore, rScO2 after exercise under normobaric conditions was associated with AMS at high altitudes.
Background:
Coronavirus disease-2019 (COVID-19) has significantly hampered the regular workflow for allergists and allergy departments.
Materials and methods:
The purpose of this review is to highlight our own experiences on SARS-CoV-2 and allergy as well as to discuss findings from the literature.
Results:
Vaccination against SARS-CoV-2 is needed for protection against severe infection. Skin reactions may arise with SARS-CoV-2 infections. Short-term general immune reactions and skin reactions are also possible upon SARS-CoV-2 vaccination; however, they recur in only a proportion of patients during follow-up vaccinations. Initial reports of anaphylaxis after vaccination fueled public fear. On the other hand, more recent epidemiologic data do not show a substantially increased anaphylaxis risk compared with other vaccines. Fear-related reactions may be essential for many “anaphylaxis” reports. In Germany, the flow chart developed by Paul-Ehrlich-Institut (PEI) and Robert-Koch-Institut (RKI) together with the allergological societies helps to care for patients with suspected “allergy history” safely and effectively. Through this, patients with increased risk of anaphylaxis to SARS-CoV-2 vaccines and their ingredients (e.g., polyethylene glycol (PEG), polysorbate 80) are identified. However, since only small amounts of these excipients are contained in mRNA vaccines, even some PEG-allergic patients can tolerate the vaccination. In Germany, an allergy test-guided procedure is recommended for high-risk patients, including an allergy history, prick tests, intradermal and basophil activation tests, and, if necessary, provocation tests. This also appears effective for anxiety reduction in patients with vaccination skepticism. To date, all of our patients have been able to be vaccinated with SARS-CoV-2 vaccines without the occurrence of significant reactions.
Conclusion:
Many initial concerns about unexpected side effects of SARS-CoV-2 vaccination have not been confirmed. The flowchart and, in the case of suspicion of hypersensitivity, an allergy test-guided risk assessment helps to reduce patients’ fear of vaccination and enables safe vaccination.
Background
Vaccination of the population is required to combat the COVID‐19 pandemic. Allergy testing could reduce anxiety towards COVID‐19 vaccination and thereby may increase vaccination rate, however, its effectiveness remains unclear.
Methods
One hundred and thirty prospective real‐life patients in need of but not daring to get vaccinated asked for allergy workup for COVID‐19 vaccine hypersensitivity in 2021/2022. Characterization of patients, identification of anxieties, decrease of patient's anxiety levels, overall vaccination rate and adverse reactions after vaccination were assessed.
Results
Tested patients were characterized by being female (91.5%) and having a high rate of previous allergies (e.g. to food 55.4%, drugs 54.6%, or previous vaccinations 50%) and dermatological disease (29.2%) but not always had medical contraindications for COVID‐19 vaccination. Sixty one patients (49.6%) were highly concerned (4‐6, Likert scale 0‐6) about vaccination and 47 (37.6%) expressed resolving thoughts about vaccinaion anaphylaxis (3‐6, Likert scale 0‐6). However only 35 patients (28.5%) were scared of getting COVID‐19 within 2 months (4–6, Likert scale 0–6) and only 11 (9%) patients had high expectations of getting COVID‐19 (4–6, Likert scale 0–6). Allergy testing significantly (p < 0.01 to p < 0.05 respectively) reduced the median anxiety of allergic symptoms following vaccination: dyspnoea (4.2–3.1), to faint (3.7–2.7), long‐term consequences (3.6–2.2), pruritus (3.4–2.6), skin rash (3.3–2.6) and death (3.2–2.6). After allergy testing, most patients (108/122, 88.5%) let themselves be vaccinated within 60 days. Revaccinated patients with previous symptoms experienced a reduction of symptoms (p < 0.05) upon revaccination.
Conclusions
Patients not daring to get vaccinated have more anxiety towards vaccination than to acquire COVID‐19. For those, allergy testing excludes vaccine allergy, and is a tool to increase vaccination willingness and thereby helps to combat vaccination hesitancy.
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