Pan-American League of Associations for Rheumatology-Central American, Caribbean and Andean Rheumatology Association Consensus-Conference Endorsements and Recommendations on the Diagnosis and Treatment of Chikungunya-Related Inflammatory Arthropathies in Latin America.

BACKGROUND/OBJECTIVE: Although mortality rates related with chikungunya (CHIK) outbreaks in Latin America's (LA's) dengue-endemic rural and new urban regions are low, dealing with symptoms and sequelae can both produce a significant burden of disease and diminish quality of life-from many months to years-after the acute phase of the infection, with a significant impact on public and individual health.The aim of this work was to establish Pan-American League of Associations for Rheumatology-Central American, Caribbean and Andean Rheumatology Association (ACCAR) consensus-conference endorsements and recommendations on the diagnosis and treatment of CHIK-related inflammatory arthropathies transmitted by Aedes aegypti and Aedes albopictus in LA. METHODS: Based on the Consensus Development Conference format, a panel of ACCAR rheumatologist voting members (n = 10) took part in this Pan-American League of Associations for Rheumatology initiative. Experts voted from a previous content analysis of the medical literature on CHIK, 4 subsequent topic conferences, and a workshop. Consensus represents the majority agreement (≥80%) achieved for each recommendation. RESULTS: The experts' panel reached 4 overarching principles: (1) CHIK virus (CHIKV) is a re-emergent virus transmitted by 2 species of mosquitoes: A. aegypti and A. albopictus; (2) CHIKV caused massive outbreaks in LA; (3) chronic CHIKV infection produces an inflammatory joint disease that, in some cases, can last for several months to years, and (4) currently, there are no vaccines or antivirals licensed for CHIKV infections. RECOMMENDATIONS: Pan-American League of Associations for Rheumatology-ACCAR achieved 13 endorsements and recommendations on CHIK categorized in 3 groups: (1) epidemiology and clinical manifestations, (2) diagnosis, and (3) treatment, representing the consensus agreement from the panel's members.

Management of immunosuppressive therapy in kidney transplant recipients with COVID-19. A multicentre national study derived from the Spanish Society of Nephrology COVID registry.

INTRODUCTION: SARS CoV2 infection has had a major impact on renal transplant patients with a high mortality in the first months of the pandemic. Intentional reduction of immunosuppressive therapy has been postulated as one of the cornerstone in the management of the infection in the absence of targeted antiviral treatment. This has been modified according to the patient`s clinical situation and its effect on renal function or anti-HLA antibodies in the medium term has not been evaluated. OBJECTIVES: Evaluate the management of immunosuppressive therapy made during SARS-CoV2 infection, as well as renal function and anti-HLA antibodies in kidney transplant patients 6 months after COVID19 diagnosis. MATERIAL AND METHODS: Retrospective, national multicentre, retrospective study (30 centres) of kidney transplant recipients with COVID19 from 01/02/20 to 31/12/20. Clinical variables were collected from medical records and included in an anonymised database. SPSS statistical software was used for data analysis. RESULTS: renal transplant recipients with COVID19 were included (62.6% male), with a mean age of 57.5 years. The predominant immunosuppressive treatment prior to COVID19 was triple therapy with prednisone, tacrolimus and mycophenolic acid (54.6%) followed by m-TOR inhibitor regimens (18.6%). After diagnosis of infection, mycophenolic acid was discontinued in 73.8% of patients, m-TOR inhibitor in 41.4%, tacrolimus in 10.5% and cyclosporin A in 10%. In turn, 26.9% received dexamethasone and 50.9% were started on or had their baseline prednisone dose increased. Mean creatinine before diagnosis of COVID19, at diagnosis and at 6 months was: 1.7 ±â€¯0.8, 2.1 ±â€¯1.2 and 1.8 ±â€¯1 mg/dl respectively (p < 0.001). 56.9% of the patients (N = 350) were monitored for anti-HLA antibodies. 94% (N = 329) had no anti-HLA changes, while 6% (N = 21) had positive anti-HLA antibodies. Among the patients with donor-specific antibodies post-COVID19 (N = 9), 7 patients (3.1%) had one immunosuppressant discontinued (5 patients had mycophenolic acid and 2 had tacrolimus), 1 patient had both immunosuppressants discontinued (3.4%) and 1 patient had no change in immunosuppression (1.1%), these differences were not significant. CONCLUSIONS: The management of immunosuppressive therapy after diagnosis of COVID19 was primarily based on discontinuation of mycophenolic acid with very discrete reductions or discontinuations of calcineurin inhibitors. This immunosuppression management did not influence renal function or changes in anti-HLA antibodies 6 months after diagnosis.

The Ppz protein phosphatases regulate Trk-independent potassium influx in yeast.

The Ppz protein phosphatases have been recently shown to negatively regulate the major potassium transport system in the yeast Saccharomyces cerevisiae, encoded by the TRK1 and TRK2 genes. We have found that, in the absence of the Trk system, Ppz mutants require abnormally high concentrations of potassium to proliferate. This can be explained by the observation that trk1 trk2 ppz1 or trk1 trk2 ppz1 ppz2 strains display a very poor rubidium uptake, with markedly increased Km values. These cells are very sensitive to the presence of several toxic cations in the medium, such as hygromicyn B or spermine, but not to lithium or sodium cations. At limiting potassium concentrations, addition of EGTA to the medium improves growth of these mutants. Therefore, our results indicate that, in addition to their role in regulating Trk potassium transporters, Ppz phosphatases (essentially Ppz1), positively affect the residual low affinity potassium transport mechanisms in yeast. These findings may provide a new way to elucidate the molecular nature of the low affinity potassium uptake system in yeast as well as a useful model to analyze the function of plant or mammalian potassium channels through heterologous expression in yeast.