This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bleeding disorder, Subject name: Pathology
A 9-year-old girl develops widespread pinpoint skin hemorrhages. She recovered from a fl u-like illness 1 week earlier. Laboratory findings reveal a platelet count of 20,000/mL but no other abnormalities. Her bone marrow shows an increased number of megakaryocytes. The platelet count is normal after 2 months. Which of the following is the appropriate diagnosis? 
Select and explain. 
A. Antiphospholipid antibody syndrome, B. Disseminated intravascular coagulation, C. Hemolytic-uremic syndrome, D. Idiopathic thrombocytopenic purpura
D: Idiopathic thrombocytopenic purpura
Answer: D: Idiopathic thrombocytopenic purpura 
Explanation: Idiopathic thrombocytopenic purpura -quantitative disorder of platelets caused by antibodies directed against platelet or megakaryocytic antigens -related to antibody-mediated immune destruction of platelets or their precursors. -The peripheral blood smear in ITP exhibits numerous large platelets, and the bone marrow shows a compensatory increase in megakaryocytes. - C/F Petechia Purpura Hemorrhagic bullae Gum bleeding Hematuria Melena *Thrombocytopenia may be observed in the other choices but is usually associated with other systemic signs and symptoms.