PATH - Chronic myeloproliferative disorders

Question 1

Chronic myeloproliferative disorders

Answer 1

The myeloproliferative disorders (polycythemia vera, essential thrombocythemia, myelofibrosis, and
CML) are malignant hematopoietic neoplasms with varying impacts on WBCs and myeloid cell
lines.

Associated with *V617F JAK2 mutation.

Question 2

Polycythemia vera

Answer 2

Chronic myeloproliferative
disorder

A form of 1° polycythemia
DEC EPO

Disorder of INC hematocrit

*intense itching after hot shower

Rare but classic symptom is *erythromelalgia (severe, burning pain and red-blue
coloration) due to episodic blood clots in vessels of the extremities

Associated with *V617F JAK2 mutation

TX: aspirin

Question 3

Essential thrombocythemia

Answer 3

Characterized by massive proliferation of megakaryocytes and platelets

Symptoms include
bleeding and thrombosis

Blood smear shows markedly *increased number of platelets, which may
be large or otherwise abnormally formed

Erythromelalgia may occur

Associated with *V617F JAK2 mutation (30-50%)

Question 4

Myelofibrosis

Answer 4

Obliteration of bone marrow with fibrosis due to  fibroblast activity

• massive splenomegaly
• “teardrop” RBCs

“Bone marrow is crying because it’s fibrosed and
is a dry tap.”

Associated with *V617F JAK2 mutation (30-50%)