Long-term antibody titers variation in unvaccinated patients receiving convalescent plasma or placebo for severe SARS-CoV-2 pulmonary infection.

BACKGROUND: Convalescent plasma (CP) became a prominent treatment in the early stages of the SARS-CoV-2 pandemic. In Argentina, a randomized clinical trial was executed to compare the use of CP in inpatients with severe COVID-19 pneumonia versus placebo. No differences in clinical outcomes or overall mortality between groups were observed. We conducted a cohort study in outpatients enrolled in the trial to describe long-term antibody titer variations between CP and placebo recipients. METHODS: Patients' total SARS-CoV-2 IgG antibodies against spike protein were collected 3, 6 and 12 months after hospital discharge from August 2020 to December 2021. In addition, reinfections, deaths and vaccination status were retrieved. Statistical analysis was performed using antibody geometric mean titers (GMT). All estimations were made considering the date of the trial infusion (placebo or CP) as time 0. RESULTS: From the 93 patients included in the follow-up, 64 had received CP and 29 placebo. We excluded all 12-month measurements because they were collected after the patients' vaccination date. At 90 days post-infusion, patients had an antibody GMT of 8.1 (IQR 7.4-8.1) in the CP group and 8.8 (IQR 8.1-9.1) in the placebo group. At 180 days, both groups had a GMT of 8.1 (IQR 7.4-8.1). No statistical differences in GMT were found between CP and placebo groups at 90 days (p = 0.12) and 180 days (p = 0.25). No patients registered a new COVID-19 infection; one died in the CP group from an ischemic stroke. CONCLUSIONS: No differences were observed in long-term antibody titers in unvaccinated patients that received CP or placebo after severe COVID-19 pneumonia.

Medicina transfusional basada en la evidencia / Evidence-based transfusional medicine

La idea de publicar este trabajo, es estimular la utilización de preguntas surgidas de la práctica médica, para obtener respuestas con base en la mejor evidencia publicada. La medicina basada en la evidencia, es una herramienta fundamental para la toma de decisiones, no sólo en lo que respecta a un paciente o caso puntual, sino también para la salud y la sociedad en general. El caso que motiva esta publicación es una de las entidades que, como equipo dedicado a la medicina transfusional más nos convoca, ya que no sólo es una patología que requiere de nuestra participación activa como integrantes de un equipo médico, sino que además depende en gran medida del desarrollo de los bancos de sangre como servicios activos y pensados para dar respuesta a este tipo de problemática.

Publishing this paper aims to encourage doctors to take questions that arise from their medical practice to be answered basing their research on the best evidence published. Evidence-based medicine is an essential tool when making decisions not only when it comes to a patient or a particular case but also when these decisions have an impact on health and societies in general. The case that inspires this publication is one that concerns us the most because it consists in a pathology that requires our whole active participation as members of a transfusion medicine team. Furthermore, it heavily depends on the development of blood banks as an active service that is conceived to salve this type of problem.

Glomérulo esclerosis focal y segmentaria. Trasplante renal y plasmaféresis / Focal segmental glomerulo sclerosis renal transplant and plasmapheresis

La Glomérulo Esclerosis Focal y Segmentaria (GEFS) primaria es una entidad que se define histológicamente por el depósito de material hialino en los glomérulos renales. Su origen permanece aún desconocido y es una de las causas más importantes del Síndrome Nefrótico (SN) Corticorresistente. La GEFS es la causa diagnostica de base del 8,3 por ciento de los casos de Insuficiencia Renal Crónica (lRC), del 14 por ciento de pacientes en plan de diálisis y del 13,5 por ciento de los receptores de Trasplante Renal. Además, luego del trasplante renal, esta enfermedad tiene una tasa elevada de recaída sobre el injerto. Sobre la fisiopatología de esta enfermedad, las últimas líneas teóricas hacen hincapié en la función de los podocitos, estos datos surgieron del conocimiento de alteraciones genéticas que implican a estas células. La hipótesis de que un "factor plasmático circulante" aumenta la permeabilidad de los glomérulos a la albumina está apoyada en numerosos estudios clínicos y experimentales. Esta es la base fisiopatológica del tratamiento donde se encuentra ubicada como uno de los pilares la Plasmaféresis, acompañando a las nuevas modalidades de Inmunosupresión. Esta revisión está focalizada en los mecanismos fisiopatológicos involucrados en esta enfermedad y a describir las terapéuticas utilizadas en su tratamiento.

Primary focal segmental glomerulosclerosis (FSGS) is an entity defined in histological terms by the hyaline material depot that is found in renal glomerulus. Its origin still remains unknown and it's one of the most important causes of corticosteroid-resistant nephrotic syndrome. FSGS is the main diagnostic cause of: 8.3 per cent of chronic renal failure (CRF) cases, 14 per cent of dialysis patients and 13.5 per cent of people receiving a kidney transplant. Besides, after the renal transplantation, this disease has a high rate relapse over the graft. Concerning the pathophysiology of FSGS, the latest theoretical research emphasizes on the podocytes function. These data came out from the knowledge of the genetic disorder that these cells implicate. The hypothesis that a "plasmatic circulating factor" increases the permeability of the glomerulus for albumin is supported by both several clinical and experimental research. The plasmatic circulating factor is the pathophysiological base for the treatment whit plasmapheresis along whit immunosuppression procedures. This present revision is focused on the pathophysiological mechanisms involved in, and des­cribes the therapies used on its treatment.