* pregnancy and breastfeeding * preadmission anticoagulation * severe renal insufficiency (glomerular filtration rate \<30 ml/min/1.73m2) * active chronic hepatitis * patients with history of allergic reaction or significant sensitivity to methylene blue * treatment with immunosuppressive agents * diagnosis of cancer at any stage and of any type. * pregnancy and breastfeeding * patients who plan to become pregnant during the study period or within 6 months after the end of the study period. * participation in another clinical trial with an experimental drug in the last 30 days. * other pathologies that, in the medical opinion, contraindicate participation in the study. * uncompensated comorbidities

* pregnancy and breastfeeding * preadmission anticoagulation * severe renal insufficiency (glomerular filtration rate \<30 ml/min/1.73m2) * active chronic hepatitis * patients with history of allergic reaction or significant sensitivity to methylene blue * treatment with immunosuppressive agents * diagnosis of cancer at any stage and of any type. * pregnancy and breastfeeding * patients who plan to become pregnant during the study period or within 6 months after the end of the study period. * participation in another clinical trial with an experimental drug in the last 30 days. * other pathologies that, in the medical opinion, contraindicate participation in the study. * uncompensated comorbidities

- pregnancy and breastfeeding - preadmission anticoagulation - severe renal insufficiency (glomerular filtration rate <30 ml/min/1.73m2) - active chronic hepatitis - patients with history of allergic reaction or significant sensitivity to methylene blue - treatment with immunosuppressive agents - diagnosis of cancer at any stage and of any type. - pregnancy and breastfeeding - patients who plan to become pregnant during the study period or within 6 months after the end of the study period. - participation in another clinical trial with an experimental drug in the last 30 days. - other pathologies that, in the medical opinion, contraindicate participation in the study. - uncompensated comorbidities

- pregnancy and breastfeeding - preadmission anticoagulation - severe renal insufficiency (glomerular filtration rate <30 ml/min/1.73m2) - active chronic hepatitis - patients with history of allergic reaction or significant sensitivity to methylene blue - treatment with immunosuppressive agents - diagnosis of cancer at any stage and of any type. - pregnancy and breastfeeding - patients who plan to become pregnant during the study period or within 6 months after the end of the study period. - participation in another clinical trial with an experimental drug in the last 30 days. - other pathologies that, in the medical opinion, contraindicate participation in the study. - uncompensated comorbidities