hem3 - pacemaker

[ArchivalUser]

A 50-year-old man is evaluated for the recent onset of pruritus while showering. He has previously been in excellent health, eats a normal diet, has never smoked, and does not take any medications.

On physical examination, there are ruddy facies and a palpable spleen tip. Results of fecal occult blood testing are negative. The oxygen saturation at rest is 99% on room air.

Laboratory studies indicate a hematocrit of 61.0% compared with a value of 44.5% documented 5 years ago, leukocyte count of 11,100/μL (11.1 × 109/L), mean corpuscular volume of 79 fL, and platelet count of 550,000/μL (550 × 109/L). Serum chemistries are normal except for a reduced serum iron saturation and serum ferritin concentration. Results of upper and lower endoscopy are normal.

Which of the following is the most appropriate management of this patient?

A Phlebotomy and anagrelide
B Oral iron supplementation and low-dose aspirin
C Hydroxyurea and aspirin, 325 mg/d
D Phlebotomy and low-dose aspirin

[ArchivalUser]

DDDDDD?

[ArchivalUser]

dddddd

[ArchivalUser]

D Phlebotomy and low-dose aspirin

[ArchivalUser]

D..

[ArchivalUser]

No I think it's A....

[ArchivalUser]

D)
Key Points

* Major diagnostic criteria of polycythemia vera include an elevated red blood cell mass, a normal blood oxygen saturation, and the presence of splenomegaly.
* Low-dose aspirin reduces the risk of thrombotic complications in polycythemia vera.

This patient's presenting symptom of pruritus while showering is typical of polycythemia vera. Major diagnostic criteria of this disease include an elevated red cell mass, a normal blood oxygen saturation, and the presence of splenomegaly. It is currently difficult to obtain a red cell mass study in many places in the United States; therefore diagnosis of polycythemia vera is frequently established by the identification of an elevated hematocrit in the absence of secondary causes of erythrocytosis. The presence of a low serum iron saturation and serum ferritin concentration in this patient reflects the increased use of endogenous iron stores as a consequence of increased bone marrow erythroid activity rather than iron deficiency caused by blood loss or decreased dietary iron consumption.

A major cause of morbidity in patients with polycythemia vera is thrombosis, which can be alleviated by lowering the hematocrit to <45% with phlebotomy or by administering hydroxyurea. Patients with polycythemia vera may also have a mildly increased leukocyte or platelet count; treatment with hydroxyurea, which lowers counts of all three hematopoietic cell lines, would be preferable to phlebotomy if the patient's platelet count were increased to >600,000/μL (600 × 109/L). The addition of low-dose aspirin has been shown to reduce thrombotic complications in polycythemia vera and should be administered in the absence of contraindications. Although phlebotomy would lower the patient's hematocrit and anagrelide can be administered to lower the platelet count, low-dose aspirin would still be a necessary component of treatment. The administration of oral iron supplementation may further increase the patient's hematocrit and increase the risk for a thrombotic complication. The use of low-dose aspirin is preferred to aspirin at a dose of 325 mg/d to prevent thrombotic complications in patients with polycythemia vera who paradoxically are also at increased risk for developing hemorrhagic complications.