Does Widespread Use of Hydroxychloroquine Reduce the Transmissibility of SARS-CoV-2 / COVID-19? An Ecological Correlational Study.

BACKGROUND: At the beginning of the coronavirus disease (COVID-19) pandemic, hydroxychloroquine (HCQ) was widely used as a possible antiviral agent. Current knowledge indicates that HCQ has little or no effect on individual clinical outcomes of COVID-19, but populational effects on disease transmissibility are still unknown. OBJECTIVE: This study investigates the hypothesis that massive HCQ consumption by a population may contribute to reducing the transmissibility of SARS-CoV-2 and COVID-19 spread by reducing the viral load of infected individuals. METHODS: Public database of seven states from Brazil in 2020 were assessed, before the start of COVID-19 vaccination. The daily values of the COVID-19 effective reproduction number (Rt) were obtained. Associations between Rt values and the proposed predictor variables (prevalence of COVID-19 as a marker of collective immunity; social isolation indices; consumption of HCQ) were tested using multiple linear regression analysis. RESULTS: In all seven states, consumption of HCQ was a significant negative predictor of Rt (ß ranged from -0.295 to -0.502, p = 0.001). Furthermore, the mean derivative of Rt during the declining period of the COVID-19 incidence (the mean rate of variation) was also significantly negatively related to the mean HCQ consumption in that period (R2 = 0.895; ß = -0.783; p = 0.011), meaning that the higher the HCQ consumption, the faster the decline of COVID-19 Rt. It suggests a dose-response phenomenon and a causal relationship in this association. CONCLUSION: The results of this study are compatible with the hypothesis that HCQ has small but significant in vivo antiviral effects that are able to reduce SARS-CoV-2 transmissibility at the populational level.

Reinforcing a medical hypothesis with a new question: is there a subgroup of shrinking lungs syndrome that is induced by pleurisy in systemic lupus erythematosus and is this subgroup marked by anti-Ro/SSA?

Shrinking lungs syndrome (SLS) is a rare entity associated with autoimmune diseases and its underlying pathogenesis is still unclear. We describe a series of seven consecutive cases of SLS in systemic lupus erythematosus, all of them with serositis and six (85.7%) with anti-Ro/SSA antibodies. Our findings reinforce the hypothesis that SLS may be, in some cases, a consequence of diaphragmatic restriction due to pleuritic pain, and we suggest anti-Ro/SSA as a marker of this subgroup of SLS.

Spontaneous pneumomediastinum and dermatomyositis may be a not so rare association: report of a case and review of the literature.

One patient with dermatomyositis (DM) who developed spontaneous pneumomediastinum (SPnM) is described. A review of 15 previously reported cases shows that this is a complication of DM but not of polymyositis. It occurs in young patients with recent onset of disease characterized by cutaneous vasculopathy, and patients treated with immunosuppressive drugs have, in general, better outcomes. We suggest that the onset of SPnM in DM patients must alert to possible vasculitic activity and that immunosuppressive agents with progressive tapering of corticosteroids are part of the most reasonable approach in these cases.