Acute onset of juvenile myelodysplastic syndrome mimicking thrombotic thrombocytopenic purpura and rapidly evolving in overt myeloid leukemia

Pancytopenia and TTP-like picture secondary to pernicious anaemia

A 21-year-old man presented to the emergency department with generalised weakness, weight loss and decreased appetite for few weeks. He had evidence of severe pancytopenia and haemolysis. His peripheral smear with many schistocytes was suspicious for thrombotic thrombocytopenic purpura (TTP). He was supported with blood transfusions and daily plasmapheresis. His platelet counts worsened despite 4 days of therapy. Bone marrow biopsy was significant for hypercellular bone marrow with megaloblastic changes. Further workup revealed normal ADAMTS13 level, low vitamin B12, positive intrinsic factor antibodies and high methylmalonic acid. Diagnosis of pernicious anaemia was established and he was started on daily treatment with intramuscular vitamin B12which subsequently improved his symptoms and haematological parameters. This report highlights the importance of checking vitamin B12level in patients presenting with pancytopenia and TTP-like picture before making a diagnosis of TTP.

Myelodysplastic Syndrome Clinically Presenting with the "Classic TTP Pentad"

The clinical presentation of myelodysplastic syndrome (MDS) is not specific. Many patients can be asymptomatic and can be detected only due to an abnormal complete blood cell count (CBC) on routine exam or for other reasons while others can be symptomatic as a consequence of underlying cytopenias. Thrombotic thrombocytopenic purpura (TTP) usually is suspected under the evidence of microangiopathic hemolytic anemia (MAHA) and thrombocytopenia and because it is a life-threatening condition (medical emergency) immediate initiation of plasmapheresis could be life-saving. The following case illustrates an unusual presentation of MDS in a patient who came in to the emergency room with the classic TTP “pentad” of fever, renal involvement, MAHA, mental status changes, and thrombocytopenia. We will focus our discussion in the clinical presentation of this case.

Chronic myelomonocytic leukemia presenting as relapsing thrombotic thrombocytopenic purpura

A 67-year-old woman presented with fever, purpura, and confusion. A preliminary diagnosis of thrombotic thrombocytopenic purpura (TTP) was made on the basis of clinical presentation and lab findings, such as reduced platelet count, increased bilirubin, and so on. She was treated with therapeutic plasma exchange (TPE) and methylprednisolone. During the treatment, peripheral blood monocytosis (monocyte 4 × 10(9)/L) was noticed. The monocytes were CD56 positive. A putative diagnosis of chronic myelomonocytic leukemia (CMML) was proposed. Three months later, the diagnosis of CMML was established on the basis of persistent monocytosis. All other potential causes were considered (e.g., quinine exposure, diarrhea) and excluded. This case highlights the needs to consider hematological malignancy such as CMML in patients with TTP.

Acute leukemia: an association with atypical hemolytic uremic syndrome

A 5-year-old boy was admitted for anemia, thrombocytopenia, and azotemia. Bone marrow examination demonstrated only erythroid hyperplasia, and he was diagnosed with an atypical form of hemolytic uremic syndrome (HUS). He was treated with daily prednisolone, and hematological profiles and renal function normalized 1 month later. However, heavy proteinuria persisted, and renal biopsy findings were consistent with HUS. Four months later, pancytopenia developed with recurrence of azotemia, and a second bone marrow examination revealed acute lymphoblastic leukemia (ALL). The remission of proteinuria with no recurrences of HUS after antileukemic treatment suggests that the HUS was associated with the ALL.