Hematology Oncology III Flashcards
What is the main cause of death in patients with paroxysmal nocturnal hemoglobinuria?
Thrombosis
e.g. hepatic, portal, or cerebral thrombosis; destroyed platelets release cytoplasmic contents into circulation, inducing thrombosis
What is the mode of inheritance of hemophilia A and B?
X-linked recessive
versus von Willebrand disease, which is autosomal dominant
What is the most appropriate pain management for a patient with advanced prostate cancer with bony metastasis, status-post orchiectomy?
Radiation therapy
bisphosphonates are useful for controlling chronic pain, but radiation is more acute; anti-androgen therapy is not needed in patients that have undergone orchiectomy
What is the most common cause of megaloblastic anemia in chronic alcoholics?
Folate deficiency
conversely, alcohol abuse is the most common nutritional cause of folate deficiency in the United States
What is the most common cause of vitamin B12 deficiency?
Pernicious anemia
often associated with other autoimmune conditions (e.g. thyroid disease, vitiligo)
What is the most common mode of inheritance of hereditary spherocytosis?
Autosomal dominant (75%)
What is the most common side effect associated with recombinant erythropoietin?
Worsening of hypertension (30%)
hypertension is generally mild, but can be severe, leading to end organ damage; other common side effects include headache (15% of patients) and flu-like symptoms (5% of patients)
What is the most common source of symptomatic pulmonary embolism?
Proximal deep leg veins (e.g. femoral, popliteal, iliac)
distal veins (e.g. calf veins) are less likely to embolize
What is the most common underlying etiology of pancytopenia in patients with SLE?
Immune-mediated destruction
What is the most important initial screening test in a Mediterranean female receiving preconception counseling due to possible thalassemia?
CBC
hemoglobin electrophoresis would be obtained only if the initial CBC is abnormal with low MCV and proof of normal iron status
What is the most likely underlying etiology of DVT in a young, Caucasian patient that presents with leg swelling, positive D-dimer, and shortness of breath?
Factor V Leiden
mutated factor V gene is unresponsive to activated protein C (an anticoagulant); most commonly inherited hypercoagulable disorder in the Caucasian population (mutated prothrombin is the second most common)
What is the next step in management for a patient with a year history of fatigue, weakness, and difficulty remembering things? Laboratory examination reveals macrocytic anemia and basophilic stippling.
Measure serum B12 and folate levels
basophilic stippling is a non-specific finding; the initial evaluation of macrocytic anemia should involve measuring folate/B12 levels
What is the next step in management for a patient with moderate-high probability of DVT (modified Wells > 2)?
Compression ultrasonography
may use D-dimer to rule-out DVT in patients with low pretest probability; diagnosis of DVT should be confirmed before anticoagulation is started if patients have no evidence of PE
What is the next step in management for an older patient with a significant smoking history that presents with painful, pruritic red streaks on the arm, with a similar episode two weeks prior on the chest that self-resolved, and mild epigastric pain?
Abdominal CT
this patient has migratory superficial thrombophlebitis (Trousseau’s syndrome), which is associated with occult visceral malignancy (pancreas, stomach, lung, prostate)
What is the pathophysiologic mechanism underlying polycythemia in patients with obstructive sleep apnea?
Increased EPO production (secondary to hypoxemia)