Is there a link between pre-existing antibodies acquired due to childhood vaccinations or past infections and COVID-19? A case control study

Background: There is growing evidence indicating that children are less affected from COVID-19. Some authors speculate that childhood vaccinations may provide some cross-protection against COVID-19. In this study, our aim was to compare the circulating antibody titers for multiple childhood vaccine antigens, as an indicator of the state of immune memory between patients with COVID-19 and healthy controls, with a specific aim to identify the association between disease severity and antibody titrations which may indicate a protective function related to vaccine or disease induced memory. Methods: This study is a case-control study including 53 patients with COVID-19 and 40 healthy volunteers. COVID-19 severity was divided into three groups: asymptomatic, mild and severe. We measured the same set of antibody titers for vaccine antigens, and a set of biochemical and infection markers, in both the case and control groups. Results: Rubella (p = 0.003), pneumococcus (p = 0.002), and Bordetella pertussis (p 0.0001) titers were found to be significantly lower in the case group than the control group. There was a significant decline in pneumococcus titers with severity of disease (p = 0.021) and a significant association with disease severity for Bordetella pertussis titers (p = 0.014) among COVID patients. Levels of AST, procalcitonin, ferritin and D-dimer significantly increased with the disease severity Discussion: Our study supports the hypothesis that pre-existing immune memory, as monitored using circulating antibodies, acquired from childhood vaccinations, or past infections confer some protection against COVID-19. Randomized controlled studies are needed to support a definitive conclusion. © 2021 PeerJ Inc.. All rights reserved

Increased renal cortical stiffness in patients with advanced diabetic kidney disease

We aimed to determine whether cortical stiffness (CS) values obtained by point shear wave elastography (pSWE) were increased in patients with diabetic kidney disease (DKD) according to increased disease stage and to determine the parameters associated with CS value in the same patient group. A total of 120 patients with Type-II diabetes mellitus who developed DKD and 22 healthy controls were included in the study. In addition to routine laboratory tests and renal ultrasonography (USG), CS levels were measured using pSWE. Carotid intima-media thickness (IMT) and aortic-IMT values were measured. Patients were grouped according to DKD stage (Stage I-II-III-IV-V), then the control group was added and, the six groups were compared within themselves. Renal CS values were found to be significantly higher in all stages of DKD than in the control group and were found to be increased in accordance with the increase in DKD stage (P 70% for parathyroid hormone (PTH), common and internal carotid-IMT, NT-proBNP, cortical thickness, and CS values. It was found that cortical thickness and PTH levels were independently associated with renal CS in DKD patients and independently determined the risk of increased CS (>9.0 kPa) in DKD patients (P <0.05). Renal CS is increased with increasing DKD stage and this is closely related to decreased cortical thickness and serum PTH levels. Renal CS measurement should be used during follow-up of a patient as part of the renal USG