heme II

Question 1

where is erythropoisesis in PT vs T?

Answer 1

in pt it’s in liver. less responsive to anemia and hypoxia (maybe to avoid polycythemia in the relatively hypoxic fetal environment). in T it’s in kidney.

overally fetal erythro-progenitors are more sensitive to epo than adults - need less epo to get the same job done

Question 2

which factors are part of intrinsic and which are extrinisic?

Answer 2

Intrinsic (PTT - normally prolonged in neonates): XII, XI, XI, VIII (all hemophilias)
Extrinsic (PT - vit K): II, V, VII, X

Question 3

what is Ddimer a product of

Answer 3

breakdown product of fibrin

Question 4

how is factor V leiden deficiency inherited, tested, and how does it present?

Answer 4

AD. Genetic screen. Presents with abnormal thrombus including renal artery thrombus, stroke
Presents in 5% of NA whites
Factor V is both intrinsic and extrinsic - cofactor to FX to convert prothrombin to thrombin. Normally Protein C binds and inactivates FV. In FVL: resistant to Protein C –> prothrombotic

Question 5

How do protein C and protein S deficiency work?

Answer 5

Protein C and S are vit K dependent factors. Thrombin activates protein C –> pC inactivates FV and VIII with the help of pS to prevent clotting.

Question 6

How does a prothrombin mutation work?

Answer 6

Actually cause hypercoagulability. Causes there to be elevated amounts of thrombin. Rare.

Question 7

is unconjugated bilirubin hydrophilic or hydrophobic?

Answer 7

hydrophobic –> binds to albumin to go into liver. Since it is hydrophobic/lipophilic, can freely cross BBB

Question 8

what is ligandin in hyperbilirubinemia?

Answer 8

ligandin transfers bilirubin from plasma to ER. low levels at birth causing slow uptake.

Question 9

when do UGDPT levels reach adult levels?

Answer 9

around 1 m of life. Low at birth. Catalyzes bilirubin to glucoronic acid making it hydrophilic.

Question 10

how does phototherapy impact bilirubin?

Answer 10

converts bilirubin in three ways:
#1: configurational isomerization to E, reversible, 20% elimination
#2: structural isomerization to lumirubin, 6% elimination, light dose dependent. Still lipophilic but can be excreted in urine/bile
#3: photo-oxidation --> bleaching, doesn't do much

Question 11

what are the different forms of hemorrhagic disease of the newborn?

Answer 11

early: 0-2d (mom meds (warfarin, seizure meds))
classic: 2-7d (poor intake, poor stores - breastfeeding, no vit K injection)
late: 7d - 6m (liver disease, poor intake (breastfeeding))
severe ICH in 60% of these cases

Question 12

Other than anti-D, which other RBC antigens cause hemolysis?

Answer 12

Kell (K1): (Kell kills) causes hemolysis and erythropoiesis suppression
Rhc: also results in moderate disease (C, e and E not so much) - c for common
Duffy: Fy a and b - moderate to severe disease from hemolysis
Lewis: hemolysis rare b/c on IgM

Question 13

which factors are elevated in the neonate, at or above adult levels?

Answer 13

factor v, viii and xiii

Question 14

how are fetal megakaryocytes different than adult ones?

Answer 14

smaller but more in number

Question 15

what is the etiology of thrombocytopenia in TAR?

Answer 15

block differentiation of megakaryocytic precursors

Question 16

what are the embryologic hemoglobin?

Answer 16

z2e2 (Gower 1), z2g2 (Gower 2), a2e2 (poland)

Question 17

when does fetal hemoglobin premonimate

Answer 17

a2g2 (z –> a; e –> g) predominates after 8 weeks

Question 18

when does HbA start revving up

Answer 18

around 30 weeks, at birth it is 60-90% of all hgb

Question 19

What is Cooley’s anemia? How does it present?

Answer 19

homozygous B thal. Presents with chronic hemolytic anemia, bilirubinemia, cholelthiasis, HSM, skeletomegaly, growth delay

Question 20

what is Hb Constant Spring

Answer 20

• two types of HbH disease (-a, –) and HbH CS (-aCS, -a)
• long unstable Hb chain, assc with a thal
• more severe than just HbH
• clinically similar to B thal major, infants may need transfusions.

Question 21

What is the use of direct and indirect Coombs in hemolysis?

Answer 21

Direct: look at baby rbc and add anti-Ab reagent. If agglutinate, then Ab present against RBC (abo or Rh)

Indirect: look at moms blood and add reagent with Rh ag. If agglutination, mom has Anti Rh Ab (Rh)

Question 22

what is the purpose of irradiation, washing and leukocyte reduced RBDs?

Answer 22

irradiation: prevent GVHD, donor T cells attack host HLA Ag. Usually after large volume transfusions. Rare by 95% mortality. Presents ~1m after transfusion.
washing: washing with NS reduces plasma by 95%, for patients at risk for severe hyperK
leukocyte reduced: decreased WBC, reduces febrile nonhemolytic transfusion reactions by 60%, viral (cytomegalovirus) transmission, and HLA alloimmunization

Question 23

what are good and bad prognosticators for neuroblastoma

Answer 23

usually presents in adrenal

bad: uniform –> more likely to grow; MYCN amplification; elevated LDH
good: cystic –> more likely to regress; 4S, Ms stage; younger than 18m a diagnosis

Question 24

what are types of renal tumors?

Answer 24

1 congenital mesoblastic nephroma (75%)

WM is very rare in nenonates, 25% assc with syndrome
rhabdoid tumor is very aggressive
clear cell carcinoma, rare but better prognosis if in neonate

Question 25

what are sites of erythropoiesis?

Answer 25

yok sac: makes embryonic hgb

liver: makes fetal hgb
bm: by 22 weeks, all in bm

Question 26

how much fetal hgb is present during different stages of the baby?

Answer 26

22w: 100%
term: 75%
6m: 5%

Question 27

when do you need cmv neg, leukoreduced and irradiated rbc?

Answer 27

cmv neg or leukoreduced always, either is fine

irradiated (to prevent gvhd) in <1500g or immunocompromised

Question 28

which gene does TMD orginate from

Answer 28

GATA gene on X chromosome, mutation for megakarycocyte transcription factor

Question 29

what components of which part of the brain can be stained by kernicterus?

Answer 29

globus pallidus, subthalamic nuclei and substantia nigra of basal ganglia

Question 30

what is the difference between howell jowel bodies vs heinz bodies

Answer 30

HJ bodies: small round nuclear remnants that can be seen in RBC with asplenia
heinz: denatured hgb seen in g6pd

Question 31

are babies more predisposed to thrombosis or hemmorhage?

Answer 31

slightly more predisposed to thrombosis

Question 32

what is the treatment for symptomatic hemmorrhagic disease of the newborn (vit K def)

Answer 32

first FFP then vit K, b/c vit K will take 4 hours to work. treat the bleed.

Question 33

what is the cause and presentation of purpura fulminans

Answer 33

causes include dic (gbs, neisseria meningitis) and congenital protein c or s deficiency.
presents as microvascular thrombosis in dermis followed by perivascular emmorhage

Question 34

what should you think of what portal vein thrombosis and what is follow up for

Answer 34

omphalitis and uvc

follow up for 10 years to evaluate for portal hypertension and liver lobe atrophy

Question 35

how are direct and indirect bili measured?

Answer 35

react with diazo reagent to create colored derivatives. indirect is catalyzed by caffeine or dmso

Question 36

when does bilirubin peak?

Answer 36

4-5 days