Hematology

Question 1

Normal retic count

Answer 1

0.5-2%

Question 2

When does physiologic anemia of infancy occur

Answer 2

2-3 months

Question 3

Lab findings in aplastic anemia

Answer 3

Hypocellular or acellular bone marrow
Platelets < 20, ANC < 0.5, retics < 20

Question 4

What is the osmotic fragility test for?

Answer 4

Hereditary spherocytosis

Question 5

Cause of
1. Febrile non-hemolytic reactions
2. Allergic reactions
3. Acute hemolytic reactions
4. GVHD
from blood transfusions

Answer 5

1. Cytokines or Abs to WBC antigens
2. Foreign plasma proteins
3. ABO incompatibility
4. Donor WBCs (why we irradiate)

Question 6

Why do we
1. Irradiate
2. Leukoreduce
blood products

Answer 6

1. Prevent GVHD
2. Reduce febrile reactions, reduce CMV transmission

Question 7

Metzner index

Answer 7

MCV/RBC
13+ = IDA
< 13 = thalassemia

Question 8

Most common complication of hereditary spherocytosis

Answer 8

Gallstones

Question 9

Is ABO vs Rh incompatibility

Answer 9

Rh more severe
ABO can occur with initial pregnancy (sensitized through diet)

Question 10

What is in
1. Crypoprecipitate
2. FFP

Answer 10

1. Fibrinogen, factor 8, factor 13, VWF
2. All factors (but less VWF)

Question 11

Lab findings in DIC

Answer 11

Increased PT and PTT
Thrombocytopenia
Decreased fibrinogen
Elevated D dimer
Increased thrombin time
RBC fragments

Question 12

5 causes of isolated PTT elevation

Answer 12

Hemophilia
Factor 11 or 12 deficiency
Lupus anticoagulant
vWD
Heparin

Question 13

4 causes of isolated INR elevation

Answer 13

Factor 7 deficiency
Early vitamin K deficiency
Early liver disease
Early/chronic DIC

Question 14

7 causes of prolonged INR and PTT

Answer 14

Factor 10 deficiency
Factor 5 deficiency
Factor 2 deficiency
Low fibrinogen
Xa inhibitors
DIC
Severe liver disease

Question 15

Risk factors for IDA

Answer 15

Prematurity
LBW
Maternal anemia or obesity
Early cord clamping
Exclusive BF > 6 mo
Infection
Lead exposure
Diet
Low SES

Question 16

Empiric abx in acute chest syndrome

Answer 16

3rd gen cephalosporin + macrolide

Question 17

Red flags in ITP

Answer 17

History: constitutional sx, bone pain, recurrent thrombocytopenia, poor response to tx
Physical: HSM, lymphadenopathy, unwell, signs of chronic disease
Labs: more than mild Hb, high MCV, abnormal WBC/neutrophil count, abnormal morphology

Question 18

NAIT treatment

Answer 18

Gold standard: washed maternal platelets
Can also do antigen compatible donors, IVIG and random donor
Threshold usually 30

Question 19

Treatment for stroke in SCD

Answer 19

Sats 95+
IV hydration not exceeding maintenance
Exchange transfusion with goal HbSS < 30%

Question 20

Screening for stroke in SCD

Answer 20

Screen annually from 2-16 years with a transcranial Doppler US
If at risk, begin chronic transfusions to maintain HbS < 30% to reduce risk of first stroke

Question 21

When does ITP typically resolve

Answer 21

75-80% within 6 months
Most resolved by 1 year

Question 22

Treatment for neonatal autoimmune thrombocytopenia

Answer 22

Limited to severe and clinically significant bleeding
IVIG, steroids, platelet transfusions if ++ serious

Question 23

How long to wait after IVIG before giving live vaccines

Answer 23

11 months

Question 24

Hereditary spherocytosis

Answer 24

Autosomal dominant
Northern Europeans
Low MCV, high MCHC
Neonatal anemia, hyper bili
Splenomegaly common after infancy, gallstones around 4-5
Can get aplastic crisis from parvo
Splenectomy is curative

Question 25

Kasabach-Merritt syndrome

Answer 25

Giant hemangiomas can have localized DIC causing thrombocytopenia and hypofibrinogenemia More in kaposiform or tufted hemangiomas Blood smear shows microangiopathic changes Normal INR/PTT

Question 26

Transient erythroblastopenia of childhood

Answer 26

Acquired red cell aplasia Children 1-3 years old Often follows a viral illness NO organomegaly or petechiae Normocytic anemia, reticulocytopenia Supportive care, resolves in 1-2 mo

Question 27

Diamond-Blackfan anemia

Answer 27

Autosomal dominant congenital red cell aplasia Presents in infancy Congenital anomalies often present Macrocytic anemia, reticulocytopenia, increased fetal hemoglobin Tx: RBC transfusions, steroids

Question 28

TEC vs Diamond blackfan

Answer 28

Both affect RBCs TEC: Normocytic, reticulopenic, no increased fetal Hb DBA: Macrocytic, reticulopenic, increased HbF

Question 29

Type 1 VWD

Answer 29

Decreased AMOUNT of vWF Most common Normal PT and aPTT AD inheritance

Question 30

Type 2 VWD

Answer 30

PT is normal aPTT is prolonged Type 2A = decreased binding to platelets Type 2B = increased binding to platelets, but bound to early so not helpful Type 2M = mix Type 2N = decreased binding to factor 8 (PT and aPTT are normal) AD except 2N which is AR

Question 31

Type 3 VWD

Answer 31

Undetectable vWF levels and low factor 8 Rare, autosomal recessive More severe symptoms (like hemophilia) Prolonged aPTT, PT

Question 32

Treatment for VWD

Answer 32

Type 1: DDAVP Type 2/3, unknown, severe bleeding: vWF/factor concentrates Could also use cryoprecipitate

Question 33

Factor 5 leiden

Answer 33

Factor 5a becomes resistant to inactivation by protein C (causes excessive clotting) Causes strokes and hemiplegic CP in neonates

Question 34

Hemophilia

Answer 34

A = factor 8, B = factor 9 deficiency X linked recessive inheritance PTT is increased, PT is normal Muscle and joint hemorrhages Treat with factor concentrates

Question 35

Hemophilia C

Answer 35

Factor 11 deficiency AR inheritance Less severe than A or B Bleeding risk does not correlate with factor levels TXA for mucosal bleeding, FFP if severe

Question 36

Fanconi anemia

Answer 36

AR inheritance Congenital pancytopenia Hyper/hypo pigmentation, cafe au lait, absent or abnormal thumbs, other congenital stuff Increased risk of hepatic and squamous cancerns HSCT will cure aplasia

Question 37

What chains are involved in: 1. HbA 2. HbF 3. HbA2 4. HbSS

Answer 37

1. 2 alpha, 2 beta 2. 2 alpha, 2 gamma 3. 2 alpha, 2 delta 4. 2 alpha, 2 S

Question 38

Beta thalassemia

Answer 38

Autosomal recessive, chromosome 16 (2 alleles) B0 = no beta = no HbA B+ = reduced beta globin = some HbA Minor: AB0 or AB+, elevated HbA2> 3.5% = diagnostic for B thal minor Intermedia: B+/B+ or B+B0, elevated HbA2 and HbF Major: B0/B0, HbF predominant

Question 39

Alpha thalassemia

Answer 39

Autosomal recessive, chromosome 16 (4 alleles) Absent or decreased alpha chains A thal trait = 1 loci, asymptomatic A thal minor = 2 loci, mild anemia HbH disease = 3 loci (4 beta chains), mod to severe Hb Bart = 4 loci (4 gamma), death in utero Hb electophoresis not sensitive enough for diagnosis

Question 40

4 naturally occurring anticoagulants and where they work

Answer 40

Antithrombin - factor 10, thrombin Protein C - factor 5, 8 Protein S - cofactor for C Tissue factor pathway inhibitor - limits activation of factor 10

Question 41

Heparin MOA

Answer 41

Binds to antithrombin Causes inactivation of thrombin and factor 5 UFH monitoring = PTT LMWH monitoring = anti-Xa Reversal = protamine

Question 42

Contact factors

Answer 42

Factor 7, high molecular weight kininogen, prekallikrein Reduced levels of contact factors = prolonged aPTT but NOT increased risk for hemorrhage

Question 43

Schwachman-Diamond

Answer 43

Severe congenital neutropenia and pancreatic exocrine insufficiency Autosomal recessive Like CF, but normal sweat test

Question 44

How to manage severe bleeding from ITP

Answer 44

Ex: prolonged epistaxis, GI bleeding, or ICH IV steroids and IVIG TXA can be used Platelet tx only for acute, life threatening bleeds or children needing immediate surgery

Question 45

Where is 1. folate 2. B12 absorbed

Answer 45

1. Jejunum 2. Terminal ileum