Cystatin C is a marker for acute kidney injury, but not for mortality among COVID-19 patients in Mexico Karime Ramos-Santos; Arturo Cortes-Telles; María Elena Uc-Miam; Azalia Avila-Nava; Roberto Lugo; Rodolfo Chim Aké; Ana Ligia Gutiérrez-Solis;

Demographic, epidemiological and clinical profile of patients with post-COVID syndrome followed at a teaching hospital in Brazil João Paulo Borges de Melo; Alex Eduardo da Silva; Leandro Resende Yamamoto; Taciana Fernandes Araújo Ferreira; Gustavo José Luvizutto; Fernando Freitas Neves; Kelly Cristina Santos; Roger Lopes Batista; Isabel Cunha Santos; Francielle Schiavoni; Mario León Silva-Vergara;

Navigating the waves in Colombia: a cohort study of inpatient care during four COVID-19 waves David E. Rebellón-Sánchez; Tania M. Guzmán; Sarita Rodriguez; Julio Llanos-Torres; Daniela Vinueza; Eric Tafurt; Estefanía Beltrán; Álvaro Martínez; Fernando Rosso;