MADRID – It involves the relationship between COVID-19 and new diagnoses of diabetes and blood glucose disorders, among others, in the post–COVID-19 period. These topics were addressed at the XXXIII National Congress of the Spanish Diabetes Society. They were also the central theme of the inaugural conference, Pancreatic Involvement During COVID-19: From Preclinical Studies to Clinical Relevance, which was led by Alexander Kleger, MD, PhD, head of the department of pancreatology at the Ulm (Germany) University Clinic for Internal Medicine.
The chair of the scientific committee of the congress, Franz Martín, MD, launched the conference by noting that the work of Dr. Kleger and his team has made it possible to ascertain that SARS-CoV-2 can infect pancreatic beta cells that produce insulin. This observation may help in understanding why patients with COVID-19 sometimes experience symptoms related to greater difficulty regulating blood glucose.
“In addition, the German expert and his group have described the abnormalities that occur in beta cells when they are infected by SARS-CoV-2, something especially important, given that knowledge of these abnormalities may be of great importance to understanding the possible appearance of more cases of diabetes in the future,” Dr. Martín added.
“Our data identify the human pancreas as a target of SARS-CoV-2 infection and suggest that pancreatic beta cell involvement could contribute to the metabolic dysregulation seen in COVID-19 patients,” Dr. Kleger pointed out.
In his speech, Dr. Kleger reviewed the evidence on the effects of SARS-CoV-2 that has been garnered since the start of the pandemic, and he presented his research group’s findings on the impact at the pancreatic level.
“Since March 2020, it has been seen that COVID-19 affected the pancreas, and studies published in August of that same year clearly spoke of both a worsening of diabetes and an increase in new cases of this disease diagnosed after SARS-CoV-2 infection. Also, the data showed how hospitalized patients with no previous history of diabetes experienced rapid increases in glucose levels 5 days after admission,” Dr. Kleger said.
Angiotensin-converting enzyme 2
As an example of the pace at which evidence on the pancreatic impact of this virus has been evolving, Dr. Kleger referred to early studies that found no angiotensin-converting enzyme 2 receptor on cells of the endocrine and exocrine pancreas. “To our surprise, in our work, we did observe the obvious presence of angiotensin-converting enzyme 2 specifically expressed in human pancreatic beta cells, something confirmed by other investigations. Another surprising aspect was verifying that the viral infection lasts longer in the pancreas than in the lungs,” said the expert.
These findings caused the researchers to realize that SARS-CoV-2 may be directly or indirectly associated with diabetes. “It is currently the subject of debate whether it may be a direct effect, infecting or directly reaching the pancreatic beta cells, or whether this involvement is a result of the effect of the infection at systemic level, in the context of the cytokine storm and the proinflammatory environment derived from it. Our current challenge is to confirm whether this virus can really replicate in pancreatic beta cells and to assess the possible existence of reinfections, among other aspects,” said Dr. Kleger.
Along with these “developing areas of knowledge,” there are several certainties regarding the link between diabetes and COVID-19. Dr. Kleger summarized the most relevant one. “Preexisting diabetes is known to be a highly prevalent comorbidity seen in 11%-22% of patients and increases the risk of severe disease and mortality.
“SARS-CoV-2 infection has also been shown to affect the exocrine pancreas, manifesting as pancreatitis in 5% of critically ill patients with COVID-19, as well as enlargement of the pancreas and abnormal levels of amylase or lipase in 7.5%-17% of patients.
“Furthermore, it is obvious that SARS-CoV-2 infection produces glycometabolic dysfunction in these patients, with increased hyperglycemia in people with type 2 diabetes and ketoacidosis in 2%-6.4% of patients with and without diabetes.”