Covid-19 and blood groups: ABO antibody levels may also matter.

BACKGROUND: Susceptibility to Covid-19 has been found to be associated with the ABO blood group, with O type individuals being at a lower risk. However, the underlying mechanism has not been elucidated. Here, we aimed to test the hypothesis that Covid-19 patients might have lower levels of ABO antibodies than non-infected individuals as they could offer some degree of protection. METHODS: After showing that the viral spike protein harbors the ABO glycan epitopes when produced by cells expressing the relevant glycosyltransferases, like upper respiratory tract epithelial cells, we enrolled 290 patients with Covid-19 and 276 asymptomatic controls to compare their levels of natural ABO blood group antibodies. RESULTS: We found significantly lower IgM anti-A + anti-B agglutination scores in blood group O patients (76.93 vs 88.29, P-value = 0.034) and lower levels of anti-B (24.93 vs 30.40, P-value = 0.028) and anti-A antibodies (28.56 vs 36.50, P-value = 0.048) in blood group A and blood group B patients, respectively, compared to controls. CONCLUSION: In this study, we showed that ABO antibody levels are significantly lower in Covid-19 patients compared to controls. These findings could indicate that patients with low levels of ABO antibodies are at higher risk of being infected.

Successful conversion from cyclosporine to tacrolimus for gastric motor dysfunction in a lung transplant recipient.

BACKGROUND: Conversion after transplantation from cyclosporine to tacrolimus is often performed because of recurrent acute/chronic rejection or unacceptable side effects such as nephrotoxicity, arterial hypertension, and cosmetic disorders. Although gastrointestinal discomfort is often reported after transplantation, it is usually not considered a sufficient reason for conversion, although tacrolimus seems beneficial with regards to gastric motor activity in renal transplant patients. METHODS: A lung transplantation was performed in a 41-year-old woman with alpha-1 antitrypsin deficiency emphysema. Because the patient presented severe symptoms of nausea, vomiting, and dyspepsia, without obvious endoscopic explanation, that resulted in highly variable cyclosporine trough levels, she was converted from cyclosporine to tacrolimus. RESULTS: After conversion, dyspepsia, nausea, and vomiting resolved. Neurological complications caused by a transient high trough level of tacrolimus resolved completely upon dose reduction with tacrolimus trough levels remaining very stable afterwards. CONCLUSION: Tacrolimus may be the immunosuppressant of choice after solid organ transplantation in patients with problems related to gastric motor dysfunction.