Leukopenia/Leukocytosis

Question 1

What is leukopenia?

Answer 1

low WBC (~<5,000 cells/mm³)

Question 2

What are the main causes of neutropenia?

Answer 2

Decreased production:

• supression of stem cells or precursors (cancer, drugs)
• ineffective hematopoiesis (precursors die in bone marrow) (MDS)
• impaired differentiation

Increased destruction/sequestration:

• immune injury to cells
• splenomegaly (sequestration)
• increased peripheral use (severe infections)

Question 3

What is agranulocytosis?

Answer 3

Decreased levels of neutrophils that there is a clinically significant change of infection.

Question 4

What is the main cause of agranulocytosis?

Answer 4

drug toxicity

Question 5

What is leukophila?

Answer 5

high WBC (~>10,000 cells/mm³)

Question 6

What are the main causes of leukocytosis?

Answer 6

Increased production in marrow:

• chronic infection/inflammation
• paraneoplastic
• myeloproliferative disorders (MPD)

Increased release from marrow:

• infection
• hypoxia

Decreased margination

• exercise
• catecholamines

Decreased extravasation:

-glucocorticoids

Question 7

What are common causes of neutrophilia?

Answer 7

• acute bacterial infections
• sterile inflammation tissue necrosis (ie. MI and burns)
• high cortisol (releases marginated neutrophils)

Question 8

What are common causes of eosinophilia?

Answer 8

-allergies

-parasitic infections

• malignacies
• drug reactions
• autoimmune disorders

Question 9

What are common causes of basophilia?

Answer 9

RARE, think myeloproliferative disorders (MPD/CML)

Question 10

What are common causes of monocytosis?

Answer 10

• chronic infections (granulomatous disease)
• autoimmune disorders
• IBS

Question 11

What are common causes of lymphocytosis?

Answer 11

• with monocytosis
• viral infections
• Bordetella pertussis (prevents lymphocyte entry into LN)