RESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved to variants associated with milder disease. We employed the k18-hACE2 mouse model to study how differences in the course of infection by SARS-CoV-2 variants alpha, delta, and omicron relate to tissue pathology and the immune response triggered. We documented a variant-specific pattern of infection severity, inducing discrete lung and blood immune responses and differentially impacting primary lymphoid organs. Infections with variants alpha and delta promoted bone marrow (BM) emergency myelopoiesis, with blood and lung neutrophilia. The defects in the BM hematopoietic compartment extended to the thymus, with the infection by the alpha variant provoking a marked thymic atrophy. Importantly, the changes in the immune responses correlated with the severity of infection. Our study provides a comprehensive platform to investigate the modulation of disease by SARS-CoV-2 variants and underscores the impact of this infection on the function of primary lymphoid organs.
RESUMEN
OBJECTIVE: Hydroxychloroquine (HCQ) is used in the treatment of inflammatory rheumatic diseases and is considered a safe drug. The role of HCQ in the COVID-19 pandemic highlighted some deleterious cardiac effects of HCQ. We aim to evaluate the prevalence and development of cardiac-adverse events in HCQ-treated patients with inflammatory rheumatic diseases. METHODS: We performed a cross-sectional study where patients aged ≥18 years with a diagnosis of inflammatory rheumatic disease currently exposed or not to hydroxychloroquine underwent electrocardiogram (ECG) and echocardiogram. Comparisons between groups were evaluated using chi-square, t test, and Mann-Whitney U test. Logistic regression was performed to determine predictors of changes in ECG and echocardiography. RESULTS: Eighty patients were included, 75 (93.8%) female, aged 52 ± 13 years. ECG changes were seen in higher proportion in patients with hypertension (40.6% vs 12.5%, p = .004) and higher median potassium levels-4.5 (4.1-4.8) versus 4.2 (4.0-4.4), p = .023. Echocardiography changes were seen in older patients (59 ± 11 vs 50 ± 13 years, p = .003) and in patients with higher cumulative dose-1752 (785-2190) versus 438 (328-1022) g, p = 0.008 - and time of exposure to HCQ - 12 (6-15) versus 4 (2-9) years, p = 0.028. HCQ cumulative dose (OR 1.001, CI95% 1.000-1.002, p = .033) and exposure time (OR 1.136, CI95% 1.000-1.289, p = .049) were predictors of echocardiography changes, but when adjusted for age, neither HCQ cumulative dose nor exposure time were predictors of echocardiography changes. CONCLUSION: No association was found between changes in ECG and echocardiogram in patients under HCQ, which remains a safe drug in patients with inflammatory rheumatic diseases.