A 14-year-old female is brought to the Urgent Care by her mother who states that the girl has had an abnormal number of bruises and “funny looking red splotches” on her legs. These bruises were first noticed about 2 weeks ago and are not related to trauma. Past medical history not remarkable and she takes no medications. The mother does state the girl is recovering from a “bad case of mono” and was on bedrest at home for the past 3 weeks. The girl noticed that her gums were slightly bleeding when she brushed her teeth that morning.
Labs at Urgent Care demonstrated normal hemoglobin and hematocrit with normal white blood cell (WBC) differential. Platelet count of 100,000/mm3 was the only abnormal finding. The staff also noticed that the venipuncture site oozed for a few minutes after pressure was released. The doctor at Urgent Care referred the patient and her mother to the ED for a complete work up of the low platelet count including a peripheral blood smear for suspected immune thrombocytopenia purpura (ITP).
Question:
What is ITP and why do you think this patient has acute, rather than chronic, ITP?