A 67-year-old woman presents to the clinic with fatigue, nau…

A 67-year-old woman presents to the clinic with fatigue, nausea, and mild confusion over the past two weeks. She also reports increased thirst and frequent urination. She has a history of smoking and unexplained weight loss over the past few months. On examination, she appears dehydrated, with mild muscle weakness but no focal neurological deficits. Laboratory results show: Serum calcium: 12.8 mg/dL (normal: 8.5–10.5 mg/dL). What is the most likely explanation for this patient’s elevated serum calcium?

A 25-year-old man presents to the clinic with a painless lum…

A 25-year-old man presents to the clinic with a painless lump in his neck that he first noticed three months ago. He reports occasional night sweats and unintentional weight loss of 10 pounds over the past few months. He denies fever, recent infections, or tenderness in the lump. A lymph node biopsy is performed and reveals a malignant proliferation of lymphoid cells. Which of the following is the most common site where Hodgkin lymphomas typically arise?

A 5-year-old boy is brought to the clinic by his parents due…

A 5-year-old boy is brought to the clinic by his parents due to excessive bruising and recurrent joint swelling after minor falls and injuries. His mother reports that he has had prolonged bleeding after minor cuts and a history of painful joint swelling (hemarthrosis). There is no family history of similar symptoms. Laboratory testing reveals: Prolonged activated partial thromboplastin time (aPTT), normal prothrombin time (PT), normal platelet count and deficiency of a coagulation factor involved in the early phase of the intrinsic coagulation pathway. What is the most likely diagnosis?