A 5-year-old boy presents with spontaneous joint bleeding and easy bruising. Laboratory tests show prolonged activated partial thromboplastin time (aPTT) and low factor VIII levels.  What is the most likely diagnosis? 

A 55-year-old female with a history of deep vein thrombosis is prescribed an anticoagulant that enhances the effects of prostacyclin.  What is the expected outcome of this therapy?

A 22-year-old female basketball player presents with knee pain and swelling after landing awkwardly from a jump. She reports hearing a “pop” at the time of injury. Physical examination reveals a positive Lachman test.  What is the most likely diagnosis? 

A 35-year-old female is diagnosed with melanoma. Genetic testing reveals a gain-of-function mutation in the BRAF gene, a proto-oncogene.  What is the primary consequence of this mutation? 

A 76-year-old man with Parkinson disease is evaluated for Pisa syndrome. He leans significantly to one side when walking. What additional symptom is likely to be contributing? 

Which substances are released to aid leukocyte chemotaxis by producing vasodilation and increased capillary permeability? 

A 65-year-old male with a history of rheumatoid arthritis presents with fatigue and joint pain. Laboratory tests show a hemoglobin level of 11 g/dL, MCV of 85 fL, and elevated inflammatory markers.  What is the most likely cause of his anemia? 

A 7-year-old girl presents with headaches, vomiting, and difficulty walking. MRI reveals a mass in the posterior fossa.  What is the most likely diagnosis? 

An 80-year-old female with a history of recurrent infections is diagnosed with a late-stage cancer.   What role does immunosenescence play in her cancer progression? 

A 45-year-old male presents with pain and numbness in his right hand and forearm. He reports that his symptoms are worse with repetitive use of his hand and wrist. Physical examination reveals tenderness in the forearm muscles and a positive Tinel’s sign at the wrist.  What is the most likely diagnosis?