Silvia Medina

BACKGROUND: The SARS-CoV-2 infection has widely spread to become the greatest public health challenge to date, the COVID-19 pandemic. Different fatality rates among countries are probably due to non-standardized records being carried out by local health authorities. The Spanish case-fatality rate is 11.22%, far higher than those reported in Asia or by other European countries. A multicentre retrospective study of demographic, clinical, laboratory and immunological features of 584 Spanish COVID-19 hospitalized patients and their outcomes was performed. The use of renin-angiotensin system blockers was also analysed as a risk factor. RESULTS: In this study, 27.4% of cases presented a mild course, 42.1% a moderate one and for 30.5% of cases, the course was severe. Ages ranged from 18 to 98 (average 63). Almost 60 % (59.8%) of patients were male. Interleukin 6 was higher as severity increased. On the other hand, CD8 lymphocyte count was significantly lower as severity grew and subpopulations CD4, CD8, CD19, and NK showed concordant lowering trends. Severity-related natural killer percent descents were evidenced just within aged cases. A significant severity-related decrease of CD4 lymphocytes was found in males. The use of angiotensin-converting enzyme inhibitors was associated with a better prognosis. The angiotensin II receptor blocker use was associated with a more severe course. CONCLUSIONS: Age and age-related comorbidities, such as dyslipidaemia, hypertension or diabetes, determined more frequent severe forms of the disease in this study than in previous literature cohorts. Our cases are older than those so far reported and the clinical course of the disease is found to be impaired by age. Immunosenescence might be therefore a suitable explanation for the hampering of immune system effectors. The adaptive immunity would become exhausted and a strong but ineffective and almost deleterious innate response would account for COVID-19 severity. Angiotensin-converting enzyme inhibitors used by hypertensive patients have a protective effect in regards to COVID-19 severity in our series. Conversely, patients on angiotensin II receptor blockers showed a severer disease.

BACKGROUND: The precise mechanism of action of dimethyl fumarate (DMF) treatment in MS remains unknown. OBJECTIVE: To identify the changes in the blood lymphocyte profile of MS patients predicting no evidence of disease activity (NEDA) status after DMF treatment. METHODS: We studied blood lymphocyte subsets of 64 MS patients treated with DMF at baseline and after 6 months of treatment by flow cytometry. NEDA (41 patients) or ongoing disease activity (ODA, 23 patients) were monitored after a year of follow-up. RESULTS: During treatment, all patients experienced an increase in the naive T cells and a decrease in effector memory ones. However, only NEDA patients showed a significant reduction in central memory CD4+ and CD8+ T cells, memory B cells, CD4+ T cells producing interferon (IFN)-gamma, CD8+ T cells producing tumor necrosis factor-alpha (TNF-alpha), and IFN-gamma and B cells producing TNF-alpha. Additionally, they had an increase in regulatory CD56bright cells not observed in ODA group. After treatment, there was a negative correlation between CD56bright cells and CD8+ T cells producing IFN-gamma and TNF-alpha. CONCLUSION: A pro-tolerogenic shift in the blood leukocyte profile associates with an optimal response to DMF in MS.

Background Gut microbiota has been related to multiple sclerosis (MS) etiopathogenesis. Short-chain fatty acids (SCFA) are compounds derived from microbial metabolism that have a role in gut-brain axis. Objectives To analyse SCFA levels in plasma of MS patients and healthy donors (HD), and the possible link between these levels and both clinical data and immune cell populations. Methods Ninety-five MS patients and 54 HD were recruited. Patients were selected according to their score in the Expanded Disability Status Scale (EDSS) (49 EDSS ≤ 1.5, 46 EDSS ≥ 5.0). SCFA were studied in plasma samples by liquid chromatography-mass spectrometry. Peripheral blood mononuclear cells were studied by flow cytometry. Gender, age, treatments, EDSS and Multiple Sclerosis Severity Score (MSSS) were evaluated at the recruitment. Results Plasma acetate levels were higher in patients than in HD ( p = 0.003). Patients with EDSS ≥ 5.0 had higher acetate levels than those with EDSS≤ 1.5 ( p = 0.029), and HD ( p = 2.97e–4). Acetate levels correlated with EDSS ( r = 0.387; p = 1.08e–4) and MSSS ( r = 0.265; p = 0.011). In untreated MS patients, acetate levels correlated inversely with CD4+ naïve T cells ( r = − 0.550, p = 0.001) and directly with CD8+ IL-17+ cells ( r = 0.557; p = 0.001). Conclusions Plasma acetate levels are higher in MS patients than in HD. In MS there exists a correlation between plasma acetate levels, EDSS and increased IL-17+ T cells. Future studies will elucidate the role of SCFA in the disease.

BACKGROUND: Cardiovascular disease is an increasing concern among HIV-infected persons and their providers. We determined if fatty liver disease is a marker for underlying coronary atherosclerosis among HIV-infected persons. METHODS: We performed a cross-sectional study in HIV-infected adults to evaluate the prevalence of and factors, including fatty liver disease, associated with subclinical coronary atherosclerosis. All participants underwent computed tomography for determination of coronary artery calcium (CAC; positive defined as a score >0) and fatty liver disease (defined as a liver-to-spleen ratio <1.0). Factors associated with CAC were determined using multivariate logistic regression models. RESULTS: We included in the study 223 HIV-infected adults with a median age of 43 years [interquartile range (IQR) 36-50 years]; 96% were male and 49% were Caucasian. The median CD4 count was 586 cells/μL and 83% were receiving antiretroviral medications. Seventy-five (34%) had a positive CAC score and 29 (13%) subjects had fatty liver disease. Among those with CAC scores of 0, 1-100 and >100, the percentage with concurrent fatty liver disease was 8, 18 and 41%, respectively (P=0.001). In the multivariate model, CAC was associated with increasing age [odds ratio (OR) 4.3 per 10 years; P<0.01], hypertension (OR 2.6; P<0.01) and fatty liver disease (OR 3.8; P<0.01). CONCLUSIONS: Coronary atherosclerosis as detected using CAC is prevalent among young HIV-infected persons. The detection of fatty liver disease among HIV-infected adults should prompt consideration of assessment for underlying cardiovascular disease and risk factor reduction.