What is the correct term to describe a platelet count of 550 ...

[nmorano1]

What is the correct term to describe a platelet count of 550  109/L when all other complete blood count (CBC) results are basically normal?
 
  a. Normal
  b. Thrombocytosis
  c. Thrombocytopenia
  d. Essential thrombocythemia

Question 2

A patient arrives at the emergency department complaining of pain in the calf of his left leg and shortness of breath. A stat D dimer is ordered. Why is this useful information for this patient's care?
 
  a. An elevated D dimer supports the possibility of deep vein thrombosis.
  b. An elevated D dimer is diagnostic for deep vein thrombosis.
  c. A normal D dimer is diagnostic for deep vein thrombosis.
  d. This was not an appropriate test to order on this patient.

[mk6555]

Answer to Question 1

ANS: B
This platelet count is elevated, so the correct terminology to describe it is thrombocytosis; this is most probably a reactive thrombocytosis. Platelets are also elevated in essential thrombocythemia, but they usually exceed 1 million/mL (1000  109/L), and other abnormalities would also be seen in the CBC.

Answer to Question 2

ANS: A
An elevated D dimer supports the possibility of a deep vein thrombosis, but it is not diagnostic. Many other clinical situations can lead to elevation of this test. A normal D dimer has negative predictive value (i.e., a normal D-dimer result is useful for ruling out deep vein thrombosis). With the patient's presenting symptoms, pulmonary embolism may also be present, which can be a consequence of deep vein thrombosis. Thus this was an appropriate requisition for this patient.

[nmorano1]

Thank you

[mk6555]

Happy to help you