This medically confirmed literature report (initial receipt 24-Jul-2012) concerns a 50 year old patient with no medical history and was not taking any medications. The patient had no history of recent illness and denied tobacco, alcohol, or illicit drug use. On an unknown date the patient received his annual influenza vaccine (batch number unknown). On an unknown date, four days after receipt of influenza vaccine, the patient presented to the emergency department (ED) complaining of bleeding gums and painless discoloration of his right hand for 1 day. The patient was unable to recall any trauma to his right hand. The patient appeared well and was in no acute distress. He had bilateral petechial lesions to the sclera with no icterus. On oral examination he had multiple petechial lesions to the soft palate. There was no active bleeding. The patient's heart, lungs, and abdominal examinations were unremarkable, and he had no evidence of lymphadenopathy or hepatosplenomegaly. He had ecchymosis to the right thenar eminence and purpuric rash over the left forearm. His vital signs were: temperature 36 degrees C (97.1 degrees F), heart rate 66 beats/min, blood pressure 108/80 mm Hg, respiratory rate 18 breaths/min, oxygen saturation 99% on room air. Laboratory tests revealed a white blood cell count (WBC) of 3.6 k/uL, hemoglobin (Hb) 15 g/dL, hematocrit (Hct) 42%, and platelet count (PLT) less than 5 k/uL. The patient's peripheral blood smear showed thrombocytopenia with no schistocytes, and no other abnormalities. The patient's prothrombin time (PT), partial thromboplastin time (PTT), and liver function tests were all within normal limits, and his HIV (human immunodeficiency virus) and hepatitis A, B, and C serology tests were negative. Abdominal ultrasound demonstrated a normal size spleen with no other abnormalities. The patient was admitted to the hospital and treated with prednisone 60 mg orally daily for 3 days with no improvement in the platelet count. On the third hospital day, he was started on intravenous immunoglobulin (IVIG) 80 g daily for 2 days. His platelet count gradually improved, and on the sixth hospital day his platelet count was 70 k/uL. The patient was discharged home on the sixth hospital day and was prescribed a prednisone taper. The patient returned to the ED 1 week after his recent discharge complaining of bleeding gums. His laboratory evaluation revealed WBC 20.6 k/uL, Hb 8.7 g/dL, Hct 25%, and PLT less than 5 k/uL. The lactate dehydrogenase was elevated at 1140 U/L, and the DAT (anti-IgG, direct antiglobulin test) was positive. The peripheral blood smear showed thrombocytopenia with occasional spherocytes and no other abnormalities. Bone marrow aspirate and core biopsy revealed hypercellular marrow with erythroid and megakaryocytic hyperplasia. There was a mild to moderate left shift of the red cell precursors and megakaryocytes. Flow cytometry showed  a normal cell profile with less than 1% blasts. The lymphocytes were phenotypically normal with polyclonal B cells and plasma cells. No features of neoplasia were found. The patient was treated with a single dose of IVIG 80 g on admission and intravenous methylprednisolone 60 mg twice daily. The patient gradually improved and was discharged home on Day 5 of his second admission, and he was prescribed prednisone. Laboratory results on the day of discharge revealed WBC 15 k/uL, Hb 9.1 g/dL, Hct 27%, and PLT 119 k/uL. At the 2-week follow up, the patient's PLT count had improved to 200 u/mL. The overall patient outcome was reported as recovering.