Impact of plasmapheresis on severe COVID-19.

The clinical course of COVID-19 may show severe presentation, potentially involving dynamic cytokine storms and T cell lymphopenia, which are leading causes of death in patients with SARS-CoV-2 infection. Plasma exchange therapy (PLEX) effectively removes pro-inflammatory factors, modulating and restoring innate and adaptive immune responses. This clinical trial aimed to evaluate the impact of PLEX on the survival of patients with severe SARS-CoV-2 and the effect on the cytokine release syndrome. Hospitalized patients diagnosed with SARS-CoV-2 infection and cytokine storm syndrome were selected to receive 2 sessions of PLEX or standard therapy. Primary outcome was all-cause 60-days mortality; secondary outcome was requirement of mechanical ventilation, SOFA, NEWs-2 scores modification, reduction of pro-inflammatory biomarkers and hospitalization time. Twenty patients received PLEX were compared against 40 patients receiving standard therapy. PLEX reduced 60-days mortality (50% vs 20%; OR 0.25, 95%CI 0.071-0.880; p = 0.029), and this effect was independent from demographic variables and drug therapies used. PLEX significantly decreased SOFA, NEWs-2, pro-inflammatory mediators and increased lymphocyte count, accompanied with a trend to reduce affected lung volume, without effect on SatO2/FiO2 indicator or mechanical ventilation requirement. PLEX therapy provided significant benefits of pro-inflammatory clearance and reduction of 60-days mortality in selected patients with COVID-19, without significant adverse events.

Combination of survival movement strategies in cyclic game systems during an epidemic.

Disease outbreaks affect many ecosystems threatening species that also fight against other natural enemies. We investigate a cyclic game system with 5 species, whose organisms outcompete according to the rules of a generalised spatial rock-paper-scissors game, during an epidemic. We study the effects of behavioural movement strategies that allow individuals of one out of the species to move towards areas with a low density of disease vectors and a high concentration of enemies of their enemies. We perform a series of stochastic simulations to discover the impact of self-preservation strategies in pattern formation, calculating the species' spatial autocorrelation functions. Considering organisms with different physical and cognitive abilities, we compute the benefits of each movement tactic to reduce selection and infection risks. Our findings show that the maximum profit in terms of territorial dominance in the cyclic game is achieved if both survival movement strategies are combined, with individuals prioritising social distancing. In the case of an epidemic causing symptomatic illness, the drop in infection risk when organisms identify and avoid disease vectors does not render a rise in the species population because many refuges are disregarded, limiting the benefits of safeguarding against natural enemies. Our results may be helpful to the understanding of the behavioural strategies in ecosystems where organisms adapt to face living conditions changes.

Relationship between diabetes mellitus and covid-19 prognosis in kidney transplant patients

Purpose: A high number of comorbidities associated with the severity of the disease caused by SARS-CoV-2 (COVID-19) has been reported, such as systemic arterial hypertension (SAH), diabetes mellitus (DM), cerebrovascular and cardiovascular diseases, obesity, chronic kidney disease, among others. Importantly, poor glycemic control in diabetic individuals and hyperglycemia at admission are associated to COVID-19 progression. To evaluate whether kidney transplant recipients with DM have worse outcomes in COVID-19 setting when compared to non-diabetics, as well as to verify whether the poor glycemic control contributes to COVID-19 progression. Methods: Retrospective analyses of 590 kidney transplant recipients who were diagnosed with COVID-19 at one single Brazilian center. We used DM, SAH and poor glycemic control as dependent variables in univariate analyses to determinant the risk factors for COVID-19 progression. Results: 60% male, 64.4% white, average age 51.6 years-old, 192 (32.6%) DM and 158 (26.8%) SAH. COVID-19-related symptoms included: fever (63.4%), chills (63.4%), cough (60.3%), dyspnea (49.3%), myalgia (46.3 %), diarrhea (32.4%), anosmia (31.2%), headache (23.7%) and runny nose (21.7%). DM was associated with acute respiratory distress syndrome (ARDS) (P=0.0001), use of supplemental oxygen (P=0.001), intensive care unit (ICU) admission (P=0.0001), mechanical ventilation (MV) (P=0.001), acute graft dysfunction (P=0.0001), hemodialysis (P=0.009), and death (P=0.0001). Fasting blood glucose prior to hospitalization was related to the risk of death (130 vs 112 mg/dL, P=0.002), MV (130 vs 119 mg/ dl, P=0.0001) and ICU admission (127 vs 109 mg/dl, P=0.0001). HbA1c values were associated with the risk of MV (7.2 vs 6.9%, P =0.031) and ICU admission (7.1 vs 6.6%, P=0.025). SAH was associated with ARDS (P=0.044), ICU admission (P=0.028), MV (P=0.018), graft dysfunction (P=0.006), HD (P=0.007) and death (P=0.037). ACE inhibitors or ARBs were not associated with the risk of death (P=0.792 and P=0.138, respectively). Conclusions: DM and poor glycemic control, as well as SAH were associated with worse outcomes in COVID-19. These findings highlight the importance of adequate management of comorbidities in transplant patients, especially in relation to DM, since poor glycemic control contributes to the worst outcomes in COVID-19. ACE inhibitors and ARBs should not be discontinued during COVID-19 pandemic, as they do not increase the risk of death.