Final answer:
The patient likely has immune thrombocytopenic purpura (ITP), and the treatment options include corticosteroids, intravenous immunoglobulin (IVIG), or platelet transfusion.
Step-by-step explanation:
Thrombocytopenia is a condition in which there is a low platelet count in the blood. The patient in this case is a 20-year-old male with recurrent bruising, hematuria, and hemarthrosis, and an increased partial thromboplastin time (PTT) that corrects with mixing studies. Based on these symptoms, the likely cause of the thrombocytopenia is an immune-mediated destruction of platelets known as immune thrombocytopenic purpura (ITP). The treatment for ITP involves the use of corticosteroids, intravenous immunoglobulin (IVIG), or platelet transfusion, depending on the severity of the symptoms.