ADAMTS13 and vitamin B12 deficiency: In contrast to TTP, in which there is no lack of substrate for DNA synthesis and a compensatory increase in erythropoiesis is observed, in vitamin B12 deficiency, there is a suppression in the bone marrow’s production of hematopoietic cells, leading to ineffective erythropoiesis, as reflected by a low reticulocyte count [3,10].