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Flashcards in Myeloproliferative disorders Deck (49)
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1
Q

What is Myeloproliferative?

A

Overproduction of cells in the bone marrow

2
Q

There are four main myeloproliferative disorders. What are they?

A

Chronic myelogenous leukemia (CML)
Polycythemia vera
Myelofibrosis
Essential thrombocytosis

3
Q

What is polycythemia vera is characterized by what?

2

A

elevated Hgb/HCT.

Elevated red cell mass (although difficult to measure)
Elevated hemoglobin and hematocrit

4
Q

There are 3 main causes of polycythemia in general. (elevated HgB and HCT)
What are they?

A

Appropriately elevated erythropoietin: hypoxemia

Inappropriately elevated erythropoietin: renal cell carcinoma, hepatocellular carcinoma

Germline and somatic mutation: polycythemia vera

Genetic production
Renal production
something wrong with erythropoeitn production

5
Q

Survival if untreated?

treated?

A

untreated is 6-18 months

If treated the survival is > 10 years

6
Q

Symptoms associated with polycythemia?

A

Headache
Weakness
Dizziness
Excessive sweating

7
Q

Demigraphic that usually gets polycythemia?

3

A

Average age at diagnosis is 60 years of age
Men more common then women
Most common is in men aged 70-79 (24 cases per 100,000)

8
Q

Hallmark symptoms of polycythemia?

2

A

Pruritus post bathing is a hallmark symptom

Erythromelalgia: burning pain in the feet and/or hands often with pallor, erythema or cyanosis

These with all the symtpoms described before

9
Q

What are the symptoms of polycythemia related to?

A

thrombosis

Arterial and venous

10
Q

Transient visual disturbances assocaited with thrombosis due to polycythemia?
2

A
Amaurosis fugax
Scintillating scotomata (opthlamic migraine, decreased retinal and choroidal blood flow due to increased blood viscosity
11
Q

GI symtpoms associated with polycythemia?

3

A

Epigastric discomfort
History of peptic ulcer disease
Gastroduodenal erosions

12
Q

Physical exam findings in polycythemia vera?

6

A
  1. Splenomegaly 70% of the time
  2. Facial plethora (ruddy cyanosis) 67%
  3. Hepatomegaly
  4. Injection of conjunctival small vessels &/or engorged veins of the optic fundus
  5. Excoriation of the skin
  6. Gouty arthritis and tophi
13
Q

Lab abnormalities in polycythemia vera?

9

A
  1. Hgb/HCT > 18.5/56 men
  2. Hgb/HCT > 16.5/50 women
  3. WBC > 10.5
  4. Platelets > 450 K
  5. Elevated serum lactate dehydrogenase (LDH is released when cells or tissue is destroyed) in 50%
  6. JAK2 mutation in 98%
  7. Abnormal serum erythropoietin in 81% (abnormally low)
  8. Hypercellular bone marrow
  9. Iron storage in bone marrow is absent
14
Q

Criteria for PV?

2

A

Hemoglobin > 18.5 g/dL in men and 16.5 g/dL

Jak2 mutation

15
Q

What is polycythemia vera treatment targeted at?
2

In which ways can we do this?
3

A

Lowering hemocrit and decreasing thrombosis

Phlebotomy to keep HCT

16
Q

What are the mylosuppressive agents that can be used in the treatment of polycythemia vera and in what situations are they used?

A

1 . Hydroxyurea- use if other treatments arent working or if at high risk for thrombosis
2. Interferon alpha- Use in womenin childbearing age or in hydroxyurea is ineffeective

17
Q

What are the symptoms of PV?

A

Pruitis
Hyperuricemia
Erythromelalgia

18
Q

How would we treat pruitis caused by PV?

7

A
  1. Antihistamines,
  2. H2 blockers,
  3. myelosuppression,
  4. interferon alpha,
  5. antidepressants such as paroxetine (Paxil) or fluoxetine (Prozac),
  6. photo chemotherapy
  7. (cool water. hotter the water the worse it will be)
19
Q

How would we treat hyperuricemia (gout) caused by PV?

A

Allopurinol for prevention

20
Q

How would we treat erythromelalgia caused by PV?

2

A
  1. Aspirin 75-100 mg daily

2. Lowering the platelet count with myelosuppresive agents also helps

21
Q

Polycythemia vera can progress to more serious disorders of bone marrow metabolism such as?
2

A

Myelofibrosis

Acute leukemia

22
Q

What is the pathology behind myelofibrosis?

What causes it?

A

Replacement of the marrow with collagenous connective tissue

Cause is generally unknown but it is associated with spent phase of polycythemia

23
Q

What are the main causes of morbidity and mortality in myelofibrosis?
5

A
Progression to acute leukemia
Infection
Bleeding
Portal hypertension
Vascular complications
24
Q

What are the most common clinical presentations of myelofibrosis? 2

What are other common manifestations seen in myelofibrosis? 5

A

severe fatigue
LUQ pain
(due to splenomegaly)

  1. Symptoms due to splenomegaly (25-50%)
    - -LUQ pain (could radiate to left shoulder)
    - -Early satiety (gastric vessels plugged up)
  2. Hepatomegaly
  3. Weight loss (5-20%)
  4. Low grade fever, night sweats (5-20%)
  5. Asymptomatic (15-30%)
25
Q

What are symptoms of myelofibrosis due to hepatomegaly?

5

A
  1. Ascites,
  2. esophageal and gastric varices,
  3. GI bleeding,
  4. hepatic encephalopathy,
  5. portal vein thrombosis
26
Q

What is extramedullary hemotopoiesis and why is it problematic?

A

When red cell production is pushed outside the bone marrow and into the surrounding tissue by the medullary tissue turning into connective tissue. It will then disrupt the tissue of that organ that it invades.

27
Q

What can extramedullary hematopoiesis present as?
(where does it go commonly)
9

A
  1. splenomegaly,
  2. hepatomegaly,
  3. lymphadenopathy,
  4. pleural effusions,
  5. pericardial effusions,
  6. abdominal effusions,
  7. GI,
  8. GU (dysuria) or
  9. Respiratory (dyspnea)
28
Q

What will a blood smear look like in someone with myelofibrosis?
2

A
  1. Marked poikilocytosis (variation in cell shape)
    - Especially with the tear-drop poikilocytes
  2. Anisocytosis
29
Q

What will a bone marrow biopsy in the early stages of PMF result in?
2

What happens has the disease progresses?

A
  1. high white count with a left shift, and a
  2. hypercellular marrow,
    - - features common to all myeloproliferative disorders

the marrow becomes replaced by fibrous tissue.

30
Q

In PMF what will the WBC look like?

A

WBC can be low or high
> 30,000 in 11%; or low in 8%
(depending on stage of disease)

31
Q

In PMF what will platelet levels look like?

A

Platelets can be low or high
> 500,000 in 13%; or low in 26%
(depending on stage of the disease)

32
Q

What lab levels will be elevated in PMF?

4

A

Elevated alkaline phosphatase
Elevated lactate dehydrogenase
Elevated uric acid
Vitamin B12

33
Q

Why is alkaline phophatase elevated in PMF?

A

Due to liver involvement or bone disease

34
Q

Why is lactate dehydrogenase Elevated in PMF?

A

Due to ineffective hematopoiesis

35
Q

Why is uric acid elevated in PMF?

A

Due to enhanced turnover of hematopoietic tissue

36
Q

Why is B12 elevated in PMF?

A

Due to increased neutrophil mass

37
Q

PMF pts might have a JAK2 mutation. What would this disrupt?

A

regulation of the production of cells in the bone marrow

38
Q

Characteristics of PMF that you need to know???

4

A
  1. bone marrow fibrosis
  2. philadelphia chromosome absence
  3. Splenomegaly
  4. Tear drop erythrocytes
39
Q

Treatment options for PMF?

6

A

Pretty limited

  1. Stem cell transplant
  2. Hydroxyurea
  3. Various chemotherapeutic agents
  4. JAK2 inhibitors:Ruxolitinib (Jakafi)
  5. Splenectomy but may cause worsening hepatomegaly and decline in liver function
  6. Radiation therapy (spleen or other sites of EMH)- not to bone marrow but to the sites of extramedullary hematopoeisis
40
Q

What is essential thrombocytosis due to?

2

A
  1. overproduction of platelets
    (isolated thrombocytosis)- clotting disorder
  2. Abnormal platelet function that can lead to thrombosis and bleeding- bleeding disorder
41
Q

How would we diagnose essential thrombocytosis?

A

elevated platelet count without other blood cell abnormalitites

42
Q

What would a peripheral smear show in a patient with essential thrombocytosis?

A

normal RBC morphology

43
Q

What would a bone marrow biopsy show in essential thrombcytosis?

A

reveals increase in number and giant megakaryocytes (platelets) but it otherwise normal

44
Q

HIGH FREQUENCY OF JACK MUTATIONS

A

STATEMENT

45
Q

Symptoms are secondary to elevated platelet count in essential thrombocytosis?
6

A
  1. Headache
  2. Lightheadedness
  3. Visual changes
  4. Numbness, tingling or burning in the feet (erythromelalgia)
  5. Splenomegaly
  6. History of thrombosis
46
Q

Where is arterial thrombosis most likely to occur?

3

A

in the hands, feet and brain but can occur anywhere (heart, larger vessels)

47
Q

Where is venous thrombosis most likely to occur?

4

A

mesenteric, hepatic and portal vein as well as deep vein thrombosis can occur

48
Q

What is the treatment targeted at for essential thrombocytosis?

And what are the treatments?
2

A

lowering the platelet count to prevent symptoms and thrombosis.

  1. Low dose aspirin (81 mg/day)
  2. Hydroxyurea to keep platelet count below 500,000
49
Q

How can essential thrombocytosis progress to worse conditions?
4

A

Bone marrow may become fibrotic

Massive splenomegaly may occur

10-15% risk of progression to myelofibrosis after 15 years

1-2% risk of progression to acute myelogenous leukemia over 20 years