Myeloproliferative disorders: Pathology review

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Myeloproliferative disorders: Pathology review

Hematological system

Coagulation disorders


Vitamin K deficiency

Leukemoid reaction

Leukemoid reaction


Myeloproliferative disorders: Pathology review

USMLE® Step 1 questions

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USMLE® Step 1 style questions USMLE

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A 58-year-old female comes to her outpatient provider’s office for symptoms of fatigue, headaches, and pruritus that is worse with showering. The symptoms began three months ago. The patient consumes half-a-pack of cigarettes per day, has a 30-pack-year smoking history, and drinks 3-4 beers per week. Her temperature is 37.0°C (98.6°F), blood pressure is 120/73 mmHg, pulse is 71/min, and respiratory rate is 14/min. On physical exam, the patient is observed to have a reddish face. Cardiac and pulmonary exams are non-contributory. Abdominal examination reveals an enlarged spleen. Laboratory testing is ordered and the results are as follows:  
 Laboratory value  Result 
 Hemoglobin  19.0 g/dL 
 Hematocrit  57% 
 Erythrocytes  7.2 million/mm3 
 Leukocytes  12,900/mm3 
 Platelets  440,000/mm3 

Which of the following additional sets of findings would be expected in this patient? 


A 70 year old female named Jenny is brought by her husband to the emergency department complaining of blurred vision and headache. Her face appears plethoric and her husband says that Jenny has been complaining of extreme itchiness after showers for the last few days. She has no significant past medical history. CBC shows increased hematocrit and slightly increased platelets. Uric acid is also increased. Next to Jenny, there’s a 65 year old male named Seth that came in with fatigue and progressive weight loss due to early satiety. Past medical history is unremarkable. Clinical examination reveals a very enlarged spleen. CBC shows pancytopenia and peripheral blood smear shows teardrop cells.

Both Jenny and Seth suffer from myeloproliferative neoplasms. These are a group of malignant neoplasms characterized by proliferation of the bone marrow cells from the myeloid lineage. That includes RBCs, platelets, as well as granulocytes, which include neutrophils, basophils, mast cells, and eosinophils. Each disorder can potentially cause proliferation of all of the myeloid cells, but they’re classified based on the dominant cell line involved. So there’s polycythemia vera, for RBCs, essential thrombocythemia for platelets, chronic myeloid leukemia, or CML, for granulocytes, and the odd one out, primary myelofibrosis, which doesn’t really have a dominant cell line, but instead is characterized by bone marrow fibrosis.

Okay, now CML is associated with the 9:22 translocation, which is when there’s fusion of the BCR gene on chromosome 22 and the ABL tyrosine kinase gene on chromosome 9. This is called the Philadelphia chromosome. Now, in this video, let’s focus on the myeloproliferative disorders that are not associated with Philadelphia chromosome, or the “Philadelphia chromosome negative myeloproliferative disorders,” like polycythemia vera, essential thrombocythemia, and primary myelofibrosis. All right, so let’s take a closer look at these myeloproliferative disorders, starting with polycythemia vera, where there’s an increase in RBC production. It typically begins with a mutation in a single hematopoietic stem cell, which gives rise to RBCs, WBCs, and platelets.


  1. "Kaplan USMLE Step 1 & 2 Lecture Notes " Kaplan Test Prep. (2018)
  2. "Robbins Basic Pathology" Elsevier (2017)
  3. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  4. "Diagnosis and Management of Polycythemia Vera: Proceedings from a Multidisciplinary Roundtable" Am Health Drug Benefits (2014)
  5. "Management of polycythaemia vera: a critical review of current data" British Journal of Haematology (2015)
  6. "Myeloproliferative Neoplasms" JAMA Oncology (2015)
  7. "Classification and diagnosis of myeloproliferative neoplasms according to the 2008 World Health Organization criteria" International Journal of Hematology (2010)
  8. " Myeloproliferative neoplasia: a review of clinical criteria and treatment" Neth J Med (2012)
  9. "Primary myelofibrosis: 2019 update on diagnosis, risk-stratification and management" American Journal of Hematology (2018)
  10. "Recent advances in the diagnosis and management of primary myelofibrosis" The Korean Journal of Internal Medicine (2018)
  11. "Essential thrombocythemia: a review of the clinical features, diagnostic challenges, and treatment modalities in the era of molecular discovery" Leukemia & Lymphoma (2017)

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