Amegakaryocytic thrombocytopenia with a positive direct Coombs' test
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Updated: Oct 13, 2026

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
1Department of Hematology-Oncology, Apollo Hospitals, Hyderabad, India.
Abstract:
A 50-year-old previously well woman developed a sudden onset of ecchymoses and petechiae over the trunk and extremities and gum bleeding. There was no history of alcohol use or drug ingestion. Physical examination was normal except for the ecchymoses, purpuric rash, and gum bleeding. Complete blood count showed Hb 8.0 g/dl, leucocytes 10.9 x 10(9)/L with a normal differential, platelets 8 x 10(9)/L and reticulocytes, 4%. The bone marrow was normocellular and showed absence of megakaryocytes; there was normoblastic erythroid hyperplasia and the myelopoiesis was normal. The direct Coombs test result was positive. There was poor response to treatment with prednisone and bolus doses of vincristine. Therapy with danazol resulted in the complete normalization of the blood counts, and the patient remains well 32 months after diagnosis and is currently taking 100 mg danazol daily.
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