Intestinal inflammation and the microbiota: Beyond diversity.

The recent manuscript entitled "Relationship between clinical features and intestinal microbiota in Chinese patients with ulcerative colitis" reported a difference in the intestinal microbiota of patients with ulcerative colitis according to the severity of the colitis. The influence of the intestinal microbiota on the development and progress of gastrointestinal disorders is well established. Besides the diversity in the microbiome, the presence of virulence factors and toxins by commensal bacteria may affect an extensive variety of cellular processes, contributing to the induction of a proinflammatory environment.

Role of vitamin D deficiency and comorbidities in COVID-19.

Recent manuscripts described the incidence of vitamin D hypovitaminosis in coronavirus disease 2019 (COVID-19) patients. Vitamin D deficiency is also common in patients with comorbidities that are associated with a poor COVID-19 prognosis. In this letter, we review the literature regarding the association of comorbidities, vitamin D deficiency, and COVID-19.

SARS-CoV-2 infection in liver transplant recipients: A complex relationship.

The recent manuscript reviewed investigations involving liver damage in coronavirus disease 2019 (COVID-19) patients, and COVID-19 in patients with previous chronic hepatological diseases, such as patients with liver graft. The literature presents several conflicting results concerning the anti-SARS-CoV-2 response in patients with solid organ transplants, in liver transplant recipients. Therefore, we would like to humbly state a few points for consideration involving liver transplant recipients and COVID-19, such as the time since transplantation, comorbidities, and immunosuppressive regimens.