Platelets

Question 1

Thrombocytosis is a count of…?

Answer 1

> 450,000/uL; recheck in about 1 week

Question 2

Thrombocytosis can be reactive which is caused by?

Answer 2

Infection, surgery or cancer

Question 3

Thrombocytosis can be caused by chronic myeloproliferative, which is?

Answer 3

Chronic myeloproliferative is a disorder of slow growing blood cancers in which the bone marrow makes too many abnormal RBC, WBC or platelets.

Question 4

There are 6 disorders that fall into the chronic myeloproliferative category. What are they?

Answer 4

1. Chronic myelogenous leukemia
2. Polycythemia vera
3. Primary myelofibrosis
4. Essential thrombocytopenia
5. Chronic neutrophilic leukemia
6. Chronic eosinophilic leukemia

Question 5

If there is just a mild increase in platelets, what do you want to consider in differential diagnosis?

Answer 5

Dehydration or chronic hypoxia (COPD or chronic carbon monoxide poisoning from smoking)

Question 6

How low are the platelets with thrombocytopenia?

Answer 6

<150,000/uL

Question 7

If platelets are 100,000-150,000/uL, when do you recheck lab?

Answer 7

1-2 months

Question 8

If platelets are 75,000-100,000/uL, and patient is asymptomatic non-bleeding, when do you recheck lab?

Answer 8

1-2 weeks

Question 9

What symptom may you see when platelets drop to 50,000-80,000/uL?

Answer 9

Petechiae or may be asymptomatic

Question 10

What happens when platelets are between 20,000-50,000/uL?

Answer 10

Bleeding risk increases

Question 11

At what count does spontaneous bleeding happen with platelets?

Answer 11

<10,000/uL

Question 12

What are some possible causes of platelet count dropping at 50,000/uL or below

Answer 12

1. Drug related, which condition will resolve within 1 week of cessation
2. Herbal products (quinine-containing; cinchona, quina, Peruvian bark)
3. Viral; HIV, Hep C, or CMV
4. Less common: liver disease w/ hypersplenism, myelodysplastic syndrome