Benign WBC Disorders

Question 1

what is the normal range of WBC (total)?

Answer 1

5K-10K / uL

Question 2

what is a normal range of platelets in CBC?

Answer 2

150K - 300K / uL

Question 3

give the normal range for the following CBC measurements:
a. RBC count
b. hemoglobin
c. hematocrit
d. reticulocytes

Answer 3

a. RBC count: 4.5-6 million/uL
b. hemoglobin: 12-18g / 100mL
c. hematocrit: 38-48%
d. reticulocytes: 1-2%

Question 4

most common form of leukocytosis

Answer 4

granulocytosis: high neutrophils (PMNs)

may see immature forms (bands) in blood during significant stress (“left shift”)

can be due to release from marrow (storage), margination, or migration into tissues

Question 5

leukemoid reaction vs leukostasis

Answer 5

secondary cause-mediated leukocytosis with WBC over 50K / uL

leukostasis: WBC over 100K —> immediately evaluate for leukemia or myeloproliferative disorder

Question 6

how do beta-adrenergic drugs and glucocorticoids affect neutrophil count?

Answer 6

increase neutrophil count (variety of mechanisms)

[remember that glucocorticoids are immunosuppressive, so count may increase but they won’t work well]

Question 7

myeloid neoplasms, Down Syndrome, and Leukocyte Adhesion Deficiency are all primary causes of….

Answer 7

high neutrophil (PMN) count

(leukocyte disorder)

Question 8

in a patient with neutrophilia (high PMN count), what would you consider if they were:
a. acutely ill
b. chronically ill

Answer 8

acutely ill —> evaluate for acute infection, examine peripheral smear for toxic granulation, Dohle body (residual RER)

chronically ill —> evaluate for inflammation and neoplastic disorders

Question 9

what are the most common causes of eosinophilia in US and in developing countries?

Answer 9

US: asthma, reaction to allergens, SLE, vasculitis, myeloid neoplasms, Hodgkin lymphoma

developing countries: Helminth infections

Question 10

if a patient has basophilia, with no other context, what is most likely the cause?

Answer 10

chronic myeloid leukemia

Question 11

if you see mononucleosis (large CTL cells with lots of cytoplasm, stuck to RBC - “kissing cells”) on peripheral smear, what are you thinking?

Answer 11

lymphocytosis associated with viral infections

Question 12

a patient presenting with more than 100K WBC count should immediately be evaluated for? (2)

Answer 12

leukemia or myeloproliferative disorder

Question 13

what is a normal WBC count and neutrophil %?

Answer 13

normal WBC count: 4.5-11K /uL with 60% neutrophils

Question 14

what neutrophil count is considered neutropenic?

Answer 14

<1500 / uL (normal 60% of 4.5-11K / uL total WBC)

Question 15

what does neutropenia + fever indicate?

Answer 15

SEVERE infection —> medical emergency