Hematology

Question 1

Hematopoiesis

Answer 1

formation, production, and maintenence of blood cells
begins in the yolk sac at 2 weeks GA
liver becomes main source by 6 weeks until 16 weeks
at 24 weeks - bone marrow main source

Question 2

Expected physiologic anemia

Answer 2

In utero, low fetal PaO2 stimulates EPO production → resulting in erythropoiesis.

After birth → relative hyperoxic environment results in suppression of EPO from 2 DOL to 6-8 weeks = expected decline in hemoglobin levels over the first 2-3 months of life with a nadir at 6-12 weeks of life.

The decline in hemoglobin (and oxygen carrying capacity) is offset by the gradual right shift in the oxy-hemoglobin dissociation curve which increases oxygen availability to tissues

resolves by 4-6 months of life

Question 3

Dose of iron supplementation

Answer 3

1 mg/kg/day to 10 mg/kg/day

Question 4

Heme is converted to ____________ by ____________.

Answer 4

heme → biliverdin by heme oxygenase

Question 5

Biliverdin is converted to ___________ by ___________

Answer 5

bilirubin by biliverdin reductase

Question 6

DIC Laboratory Indicators

Answer 6

• thrombocytopenia
• Elevated Fibrin Degradation Products (FDP)
• Elevated D-Dimers
• Prolonged PT
• Prolonged PTT

Question 7

DIC management

Answer 7

treatment of underlying cause

platelet transfusions, FFP, or cryo

Question 8

DIC patho

Answer 8

activation of blood clotting proteins is initiated by tissue factor from bacterial products (endotoxins)

→ leads to hypercoagulable state

→ thromboses form (especially in the small vessels of the liver, kidneys, spleen, brain, adrenal glands

→ bone marrow releases platelets

system regulating coagulation is immature and is quickly overwhelmed

results in a deficiency of platelets and clotting proteins

Question 9

Management of asymptomatic and symptomatic polycythemia

Answer 9

asymptomatic infants with HCT >60-70% can be managed with increased fluid intake

symptomatic infants may require a partial exchange transfusion to dilute circulating blood volume

Question 10

Normal platelet count in neonate

Answer 10

150k - 450k

Question 11

Neonatal Alloimmune thrombocytopenia

Answer 11

antibody is produced in the mother against a specific human platelet antigen (HPA) present in the fetus but absent in the mother

tx: random platelets; test infant for HPA, in absence of HPA, maternal platelets indicated

Question 12

neonatal autoimmune platelets

Answer 12

should be considered in any early onset thombocytopenia with maternal hx of ITP or autoimmune disease;

tx: IVIG + random donor platelets for active bleeding

Question 13

vitamin K dependent clotting factors

Answer 13

factor II, VII, IX, X

Question 14

Early Onset Vitamin K Dependent Bleeding Disorder

Answer 14

within 24 hours - usually a result of maternal anticonvulsants or vitamin K antagonists such as warfarin

Question 15

Classic Vitamin K Deficient bleeding disorder

Answer 15

DOL 2-6 : results because of physiologic deficiency of vitamin k and exclusive breastfeeding or inadequate feeding

Question 16

Late Onset VKBD

Answer 16

2-12 weeks of age; results in infants who did not receive vitamin K at birth and are receiving inadequate dose (exclusive breastfeeding,ect.) or in infants with hepatobiliary disease

Question 17

VKBD treatment

Answer 17

transfusions of blood products (PRBCs, FFP) and repeated doses of vitamin K

Question 18

VKBD lab indicators

Answer 18

elevated PT and PTT, low levels of vitamin K dependent clotting factors

Question 19

Biliary Atresia

Answer 19

inflammation and fibrosis of the bile ducts;

one of the most common causes of chronic liver disease

Question 20

BA symptoms

Answer 20

presentation between 2-5 weeks with acholic stools;

cholestatic or prolonged jaundice;

ascites may present later in disease course

conjugated bili >2mg/dL

elevated total serum bili

elevated ALT, ALP, GGT

Question 21

_________ bilirubin is able to cross the blood-brain barrier

Answer 21

unconjugated

Question 22

Phototherapy mechanism

Answer 22

converts unconjugated bilirubin to photoisomers (lumirubin) that can be excreted without conjugation

Question 23

polycythemia risk factors

Answer 23

baby’s risk factors: IUGR, SGA, post-term, delayed cord clamping

maternal risk factors: insulin dependent diabetes, hypertension, smoking, living at high altitude

Question 24

polycythemia clinical manifestations

Answer 24

CNS: lethargy, irritability, jitteriness

RDS: tachypnea, pulmonary edema, pulmonary hemorrhage, PPHN

Cardiac: tachycardia, cyanosis, CHF, murmur, cardiomegaly

renal: renal vein thrombosis, hematuria, proteinuria

GI: Poor feeding, decreased bowel sounds, abdominal distention

increased risk of hyperbili

Question 25

Most Common Cause of Late-Onset Thrombocytopenia (>72 hours)

Answer 25

Sepsis

Question 26

hematopoiesis

Answer 26

the process of pluripotent stem cells delineation into different blood cells

Question 27

erythropoiesis

Answer 27

the maintenance and production of red blood cells

Question 28

site of erythropoietin production

Answer 28

after delivery, EPO is produced in the kidneys

Question 29

Treatment of hemophilia ( unknown factor)

Answer 29

Fresh Frozen Plasma contains all clotting factors (Cryo is missing factor IX)

Question 30

Lab Indicators of Hemophilia

Answer 30

prolonged aPTT, normal PT, normal platelet count

Question 31

normal aPTT

Answer 31

30.5-39.5

Question 32

normal PT value

Answer 32

12.2-14

Question 33

Hemophilia A (most common) is a deficiency of factor ____

Answer 33

VIII

Question 34

Maternal Transfer of ____ antibodies provide the newborn with a measure of passive immune protection and are the only ones to cross the placenta in significant amounts (after 20-22 weeks GA)

Answer 34

IgG

Question 35

Antibodies that evoke primarily _____ or _____ antibody responses are poorly transported across the placenta

Answer 35

IgA or IgM

Question 36

Early Onset Sepsis commonly occurs _________ and is ________ acquired during __________,

Answer 36

before 72 hours and is acquired horizontally during birth

Question 37

Most common organisms for Early Onset Sepsis

Answer 37

Group B Streptococcus, E. Coli, Listeria monocytogenes

Question 38

Late onset Sepsis

Answer 38

occurs after the first week of life (or as early as DOL 3)

Question 39

Treatment for Early onset sepsis

Answer 39

ampicillin and gentamicin until organism is confirmed

Question 40

Treatment for late onset sepsis

Answer 40

Vanc and Gent until organism confirmation

Question 41

ANC (absolute neutrophil count)

Answer 41

predictive of infection if <1000

%WBCs x (% Immature neutrophils + % mature neutrophils) x 0.01

Question 42

I/T Ratio

Answer 42

%Bands + %Immature Forms
%Mature + %Bands + %Immature Forms

most informative from 1-4 hours after birth

normal <0.2

Question 43

Immature Neutrophils

Answer 43

bands, myelocytes, metamyelocytes

Question 44

Neutrophils also known as ….

Answer 44

segs, polys, polymorphonuclear leukocytes (PMNs)

Question 45

Hydrops

Answer 45

a prenatal form of heart failure almost always caused by fetal anemia; characterized by subcutaneous edema and fluid in 2 compartmental spaces

result of imbalance of interstitial fluid and lymphatic return

2 types: immune and non-immune

Question 46

Immune Hydrops

Answer 46

maternal antibodies cross the placenta and attack and destroy fetal RBCs; seen in Rh and ABO incompatibility

Question 47

Nonimmune hydrops

Answer 47

disease or anomalies interfere with fetal fluid management;

• cardiovascular (most common cause)
  
  • dysrhythmias: SVT, atrial flutter, heart block
  • cardiac malformation: left and right outflow obstructions
  • myocarditis
• chromosomal: aneuploidy, including trisomies 13,18,21, triploidy, and 45, X (turners), achondroplasia
• inborn errors of metabolism
• LONG LIST with conditions under each system