Pediatric WBC/Neutropenia

Question 1

What is the order of WBC #? Remember the pneumonic

Answer 1

Neutrophils > lymphocytes > monocytes > eosinophils > basophils

Never let monkeys eat bananas

Question 2

What is the formula for ANC

Answer 2

(%neutrophils + %bands) x WBC / 100

Question 3

What is the definition of neutropenia?
Mild vs moderate vs severe
What is assoc w/ severe neutropenia

Answer 3

Neutropenia is ANC <1500
Mild 1000-1500, moderate 500-1000, and severe <500
Severe neutropenia is assoc w/ inc risk of severe infection

Question 4

What is Kostmann syndrome?

Does it inc the risk of malignancy and if so what type?

Answer 4

Kostmann syndrome is autorecessive severe congenital neutropenia leading to life threatening pyogenic infections in infants due to impaired myeloid differentiation leading to maturation arrest of neutrophilic precursors
Inc risk of AML

Question 5

What is cyclic neutropenia?

Does it inc risk of malignancy and if so what type?

Answer 5

Cyclic neutropenia is sporadic or autodom disorder characterized by cyclic fever, oral ulcers, gingivitis, periodontal diseae, and recurrent bacterial infections due to defects in stem cells leading to defective maturation
Does not inc risk of malignancies

Question 6

What is Shwachman Diamond syndrome?

Does it inc risk of any malignancy and if so what type?

Answer 6

Schwachman diamond syndrome is autorecessive disorder characterized by triad of neutropenia, pancreatic insufficiency, and skeletal abnml due to defective neutrophil mobility, migration, and chemotaxis
SD syndrome inc risk of MDS and leukemia

Question 7

What is Fanconi Anemia?

When does it present in life? What cells does it affect?

Answer 7

Fanconi anemia is autorecessive bone marrow failure characterized by GU and skeletal abnml and chrom fragility
Presents in first decade of life and affects all cell lineages

Question 8

What is Leukocyte Adhesion Deficiency?

Answer 8

LAD is rare autorecessive disorder characterized by delayed separation of umbilical cord for >3 weeks and recurrent severe bacterial/fungal infections w/o pus due to dec neutrophil adhesion

Question 9

What is Chronic Granulomatous Disease?

Whats the prognosis? How common/rare is it?

Answer 9

Chronic granulomatous disease is characterized by recurrent purulent infection by catalase + orgs in infants leading to chronic inflammatory granulomas due to defects in oxidative metabolism leading to absence of superoxide
Good prognosis; affects 1 in 250,000

Question 10

What is infection assoc neutropenia?

Explain B19 parvovirus

Answer 10

Infection assoc neutropenia- viral infections lead to neutropenia w/in 3 days and lasts about 1 week
B19 parvovirus causes 5ths disease characterized by slapped check appearance that causes neutropenia 1-2 weeks post infection

Question 11

What are 2 additional causes of pediatric neutropenia?

Answer 11

Cytotoxic agents and b12 deficiency

Question 12

What is leukocytosis

What are 3 additional assoc with it?

Answer 12

Leukocytosis is reactive process to infection that subsides w/ resolution of infection
Chronic inflammation- autoimmune disorders
Oncogenic processes- leukemia, lymphoma, neuroblastoma
Seizures

Question 13

What is the most common general cancer type affect adolescents?

Answer 13

Lymphomas

Question 14

What is the most common cancer affecting 15-19 yo?

Answer 14

Hodgkins lymphoma

Question 15

What is a pathognomoic morph feature of HL?

Answer 15

Reed sternberg cells

Question 16

What type of symptoms is HL assoc w/ and what are they?

Answer 16

HL assoc w/ B symptoms

Unexplained fever over 39, night sweats, and wt loss >10% of body mass in past 6 months

Question 17

What is general rule for diagnosis of HL w/ regards to when you should get a LN biopsy?

Answer 17

Any pt w/ unexplained persistent LAD that is not related to inflammatory or infectious processes should undergo a chest radiograph to rule out mediastinal mass prior to having a LN biopsy

Question 18

NHL accounts for what % of lymphomas affecting children and adolescents?

Answer 18

60%

Question 19

A small % of NHL is assoc w/ acquired/inherited immunodeficiencies, what are they and explain

Answer 19

SCID
X linked Wiscott syndrome characterized by recurrent sino-pulm and ear infections, severe atopic dermatitis, and bleeding secondary to thrombocytopenia

Question 20

Burkitts Lymphoma
Where does sporadic form arise?
Where does endemic form arise and w/ what else involved?

Answer 20

Sporadic BL- arises as abdominal mass

Endemic BL- arises as head/neck mass w/ CNS and BM involvement

Question 21

NHL Prognosis
Localized
Advanced
What does prognosis depend on

Answer 21

Localized NHL- >90% survivial
Advanced NHL- 60-95% survival
Prognosis of NHL depends on patho subtype, tumor burden at time of diagnosis based off LDH levels, sites of spread, and whether or not there is CNS disease along with it

Question 22

What are the 2 most common types of cancers affecting children?

Answer 22

Leukemias and brain tumor

Question 23

Explain how leukemia arises?

Answer 23

Leukemias arise due to malignant transformation and clonal expansion of hematopoietic cell at early stage of differentiation that is unable to undergo maturation

Question 24

What are the 2 general classes of leukemias? Think general WBC neoplasm classes

Answer 24

Lymphoid and myeloid

Question 25

What % of childhood leukemias are acute or chronic and what are the 2 major examples

Answer 25

More than 97% of childhood leukemias are acute; most commonly ALL or AML

Question 26

What common genetic disorder inc the risk of childhood leukemia?

Answer 26

Trisomy 21 inc risk of childhood leukemia

Question 27

With anemia what happens to [2,3-DPG]? What does that do to the O2 dissociation curve and O2 binding affinity?

Answer 27

With anemia 2,3-DPG concentration inc in RBC causing a right shift in O2 dissoc curve which causes Hb to have dec binding affinity to O2

Question 28

What is MCV? | How can it be used to classify anemias?

Answer 28

MCV Mean corpuscle vol- represents the mean value of the vol of individual RBC in a sample MCV low (microcytic), MCV nnml (normocytic), MCV high (macrocytic)

Question 29

Whats MCHC? | How it is used to classify anemias?

Answer 29

MCHC Mean corpuscular Hb concentration- grams of Hb per 100 mL of RBC MCHC low (hypochromatic), MCHC nml (normo), MCHC high (hyperchromatic)

Question 30

What is MCH?

Answer 30

MCH presents average amount of Hb per RBC

Question 31

Whats RDW?

Answer 31

RDW | RBC distribution width- measure of anisocytosis

Question 32

What does a peripheral smear allow us to evaluate w/ regards to RBC?

Answer 32

We can use peripheral smears to evaluate RBC morph change

Question 33

Dec RBC production in marrow is due to what 2 causes?

Answer 33

Dec RBC production in marrow is due to ineffective hematopoiesis/MDS or marrow/erythropoeisis failure

Question 34

Intravascular hemolysis results in what?

Answer 34

Anemia, hemoglobinemia, hemoglobinuria, hemosiderinuria, jaundice, dec haptoglobin, hemosiderosis due to free iron, and free Hb is oxidized to methamoglobin and excreted causing dark urine

Question 35

Extravascular hemolysis causes what?

Answer 35

Anemia splenomegaly and jaundice

Question 36

Blood loss anemia is classified in what two categories?

Answer 36

Acute and chronic blood loss anemia

Question 37

What does a low reticulocyte count indicated during anemia?

Answer 37

Low reticulocyte count indicates inadequate marrow response to anemia due to ineffective hematopoiesis or due to marrow failure

Question 38

What does a high reticulocyte count indicate during anemia? What causes the anemia?

Answer 38

High reticulocyte count represents a nml marrow response to anemia meaning the anemia is do to blood loss, hemolysis, or due to splenic sequestration

Question 39

What is the physiologic nader

Answer 39

At about 2 months old fetal Hb and Hct will dec after initially being elevated very high before rising to a nml value

Question 40

What are the 5 neonatal causes of anemia?

Answer 40

Isoimmunization, congenital hemolytic anemia, B19 parvovirus, shwachmann diamond syndrome, and fanconi anemia

Question 41

Explain neonatal anemia due to isoimmunization

Answer 41

Isoimmunization occurs due to ABO incompatability and results in positive direct coombs test, elevated unconjugated bilirubin, elevated reticulocyte, and normocytic anemia

Question 42

Explain neonatal anemia due to congenital hemolytic anemia

Answer 42

G6PD Deficiency- Heinz bodies and bite cells | Pyruvate Kinase Deficiency- spur cells

Question 43

Explain B19 parvovirus w/ regards to neonatal anemia

Answer 43

Normocytic w/ low reticulocyte count

Question 44

Explain diamond syndrome w/ regards to neonatal anemia

Answer 44

diamond syndrome causes congenital pure RBC aplasia leading to macrocytic and low reticulocyte

Question 45

Explain fanconi anemia w/ regards to neonatal anemia?

Answer 45

Macrocytic, reticulocytopenia, and pancytopenia

Question 46

What are the 3 causes of infancy anemia

Answer 46

Iron deficiency Defective Hb structure or synthesis Lead Poisoning

Question 47

Explain iron deficiency w/ regards to infancy anemia

Answer 47

Iron anemia causes microcytic hypochromatic anemia w/ low iron/ferratin and high transferrin Due to low dietary iron (milk rich diet) or chronic occult blood loss

Question 48

Explain defective Hb structure/synthesis w/ regards to infancy anemia?

Answer 48

Microcytic, dec RDW, dec Mentzer index in thallassemias, basophilic stippling, hemolysis, and reticulocytosis

Question 49

Explain lead poisoning w/ regards to infancy anemia?

Answer 49

Microcytic w/ basophilic stippling | Risks- young age, house built before 1970, contaminated soil, and pica