Myelodysplastic syndrome (MDS) is a hematologic malignancy characterized by clonal hematopoiesis, one or more cytopenia (i.e., neutropenia, anemia and/or thrombocytopenia), and abnormal cell maturation.  Acute myeloid leukemia (AML) is a type of cancer arising from the clonal expansion of malignant hematopoietic precursor cells in the bone marrow in which the bone marrow produces abnormal myeloblasts, platelets, and red blood cells. Leukemic cells interfere with the production of normal blood cells. The connection between MDS and AML is very well established, and it is known that one disease evolves into the other. However, the involvement of a thrombotic thrombocytopenic purpura (TTP) is not correlated. TTP is a thrombotic microangiopathy caused by greatly reduced activity of the ADAMTS13 protease that results in platelet fragmentation by uncleaved von Willebrand multimers and subsequent formation of blood clots in the entire microvasculature body We present a case of a MDS that progressed to AML with changes related to myelodysplasia that debuted as TTP. He presented to the emergency department with a quantified fever of up to 38.5 ° C, asthenia, adynamia, nausea, vomiting, edema of the lower extremities Godet +++ and altered mental status, each of which he had been present for the last 7 days. Physical examination found an overweight and stuporous man without acute distress, generalized jaundice, hepatosplenomegaly, and disseminated petechiae in bilateral palms and bilateral lower extremities, as well as generalized edema (palpebral, upper extremities, ascites, testicular and lower extremities). Relevant laboratory tests reported the following: ADAMTS13 activity 0.5%, pancytopenia and lactic acid dehydrogenase 950 UI/L. After a failure in response to plasmapheresis therapy and a poor long-term prognosis, the family opted for palliative care, the patient dying on the eleventh day of hospitalization. The case is an extremely rare presentation of a rare condition, as it is the second reported case of AML with myelodysplasia-related changes presenting as TTP, and the first reported case of TTP secondary to AML secondary to MDS.

Keywords: Thrombotic thrombocytopenic purpura, Acute myeloid leukemia, Myelodysplastic syndrome, Microangiopathic hemolyticanemia

Abbreviations: Myelodysplastic syndrome (MDS); Acute myeloid leukemia (AML); thrombotic thrombocytopenic purpura (TTP)