Case discussion:
A 25-year-old Caucasian female with no significant past medical history except for well controlled bronchial asthma presented to us with two-day history of worsening petechiae that initially started on her face and lower extremities and eventually spread to back, chest, abdomen and upper extremities. She also complained of intermittent epistaxis.
Vital signs on initial presentation including blood pressure, heart rate and oxygen saturation were normal. Physical examination revealed extensive bruising over her back, chest and extremities along with scattered petechiae all over the body. Laboratory findings on presentation include WBC of 11x109/L, hemoglobin (Hb) of 11g/dl and severe thrombocytopenia with a platelet count of 1x109/L. Prothrombin time (PT/INR), activated partial thromboplastin time (aPTT), fibrinogen, Lactate dehydrogenase (LDH), absolute reticulocyte count and haptoglobin levels resulted normal. Peripheral blood smear showed profound thrombocytopenia with no evidence of schistocytes. RT-PCR testing for SARS CoV-2 infection was negative. Autoimmune and infectious workup including antinuclear antibody (ANA) screening, coombs testing, HIV ELISA and serology for hepatitis B, and C were negative. Ultrasound of the abdomen did not show evidence of splenomegaly or liver parenchymal changes.
Her most recent hematological labs including Hb, platelet count from three months ago during routine primary care visit were within normal limits. She neither reported personal or family history of bleeding disorders nor required blood transfusions prior to this presentation. 26 days prior to this presentation she had received her second dose of Moderna mRNA vaccination.
Given her clinical presentation, negative infectious and autoimmune workup, normal hemolysis and coagulation studies along with absence of other identifiable underlying etiology, she was presumed to be having immune mediated thrombocytopenic purpura (ITP) and was initiated on dexamethasone 40mg daily for four days along with intravenous immunoglobulin (IVIG) 1g/kg for two days. She continued to have clinical worsening during the second and third day of hospitalization and developed multiple bleeding sites including gross hematuria, hematochezia, subconjunctival hemorrhage. Her hemoglobin dropped from 11g/dl on presentation to 6.4g/dl. She was initiated on tranexamic acid for bleeding control and supportive care with platelet transfusions. Her platelet counts continued to remain low (5x109/L) despite receiving 4 days of dexamethasone, 2 days of IVIG and platelet transfusion support. She continued to have intermittent epistaxis however hematuria and rectal bleeding started improving with Tranexamic acid initiation.
As there was no improvement in platelet counts with IVIG and dexamethasone, on day 7 she was initiated on mycophenolate mofetil (MMF) 1 gram twice daily and Romiplostim 1 mcg/kg weekly. On day 12 her platelet counts for the first time improved to 13x109/L. Hb remained stable around 11g/dl. She was discharged after receiving second dose of Romiplostim 3mcg/kg on day 14. During her first outpatient visit on day 21 her platelet counts improved to 140x109/L. She went on to receive third dose of Romiplostim at 3mcg/kg. She continued to have no active sites of bleeding. During fourth week follow up, platelet count recovered to 268x109/L and MMF was tapered down to 500mg twice daily and Romiplostim to 2mcg/kg. By fifth week, her platelet counts continued to improve to 324x109/L and MMF was tapered to 250mg twice daily and Romiplostim to 1mcg/kg. She continued to have normal and stable platelet counts and eventually MMF and Romiplostim were discontinued.