Hematology Flashcards
(124 cards)
1
Q
Anemia
A
2 SD below normal for age/sex
Hgb concentration <11g/dL for both male and females aged 6 mo - 5 yrs
2
Q
Labs for anemia
A
CBC w/ diffferential
peripheral blood smear
reticulocyte count
3
Q
Reticulocyte results
A
high- bone marrow working
low- trouble
4
Q
normocytic, normochromic anemia
A
anemia of chronic disease
5
Q
microcytic, hypochromic anemia
A
IDA
thalassemia
lead intoxication
6
Q
Macrocytic anemia
A
vitamine b12
folate deficiency
7
Q
S/sx of anemia
A
acute: lethargic, tachy, pallor; infants - irritable, poor oral intake
chronic: may present w/ few or no sx at all
8
Q
Other findings w/ anemia
A
jaundice gallstone disease petechiae purpura ecchmosis bleeding
9
Q
Types of bone marrow failure
A
fanconi anemia
acquired aplastic anemia
10
Q
What is fanconi anemia
A
inherited bone marrow failure syndrome
auto recessive
defective DNA repair
majority develop in first 10 years of life
11
Q
Clinical manifestation of fanconi anemia
A
progressive panctyopenia abnormal pigmentation short stature skeletal malformation increased incidence of malignancies
12
Q
Lab findings for fanconi
A
thrombocytopenia or leukopenia (then followed by anemia)
anemia = severe aplastic anemia
bone marrow hypoplasia or aplasia
13
Q
Fanconi anemia may be misdiagnosed as
A
ITP
14
Q
Tx for fanconi
A
supportive
HSCT
15
Q
Prognosis for fanconi
A
many succumb to bleeding, infection, or malignancy in adolescence or early adult
high risk for developing Myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML)
16
Q
Acquired aplastic anemia
A
peripheral pancytopenia w/ a hypocellular bone marrow
idiopathic (50%)
meds, toxic exposure (insecticides) and viruses (mono, hepatitis, HIV)
17
Q
S/sx of acquired aplastic anemia
A
weakness, fatigue, pallor
frequent or severe infections
purpura, petechiae, bleeding
18
Q
Lab findings for acquired aplastic anemia
A
anemia, usually normocytic
low WBC w/ marked neutropenia
thrombocytopenia
low reticulocyte count (bone marrow suppressed)
19
Q
Complications of acquired aplastic anemia
A
overwhelming infection
severe hemorrhage
can lead to death
20
Q
Tx for acquired aplastic anemia
A
supportive referral stop offending agent abx if infection RBC transfusion for severe anemia Platelet transfusions immunosuppressant agents HSCT
21
Q
Most common nutritional deficiency in children
A
Iron deficiency
22
Q
Prevalence of IDA
A
1-2 yo
females of chldbearing age
african american and hispanics
poverty
23
Q
S/sx of IDA
A
varies w/ severity pallor fatigue, irritability delayed motor dev. hx of Pica (eating ice)
24
Q
Screening for IDA
A
12 months- determine Hb concentration and assessment of risk factors
25
Risk for IDA
low SE status
premature/LBW
lead exposure
exclusive breast feeding beyond 3 mo of age w/o iron supplementation
weaning to whole milk or foods w/o iron
feeding problems, poor growth, inadequate nutrition
26
Lab findings for IDA
microcytic, hypochromic
Hb <11 g/dL
Ferritin <12 mcg/L
27
Tx for IDA
Hb 10-11 mg/dL @ 12 mo screening-- monitor closely or empirically treated; recheck Hb in one month
ID/IDA: iron 6 mg/kg/d, 3 divided daily doses
28
Cobalamin
vitamin B12
29
Causes of b12 deficiency
malabsorption
| dietary insufficiency
30
Folic acid deficiency
increased folate requirement (rapid growth, chronic hemolytic anemia)
malabsorptive syndromes
inadequate dietary intake (rare)
Medications
31
S/sx of megaloblastic anemia
pallor
| glossitis
32
B12 sx
paresthesias, weakness, unstead gait
decreased vibratory sensation and proprioception on enuro exam
neuro sx only occur w/ B12 not folate
33
Neuro sx
B12 deficiency
34
Lab findings for megaloblastic anemia
elevated MCV/MCH
low levels of folic acid or vit B12
neutrophils large and hypersegmented nuclei
Macro-ovalocytes (large, ocal RBC)
Elevated Methylamlonic acid w/ 12
Elevated homocysteine w/ B12 and folate deficiency
35
How to tell the difference between B12 and folate?
Methylmalonic acid elevated in B12
36
Hypersegmented nuclei
megaloblastic anemia
37
Tx for megaloblastic anemia
Vit B12 and/or folic acid supplementation
****tx w/ folate will fix anemia picture in B12 BUT...must treat vit B12 to avoid neuro deficits
38
Congenital hemolytic anemias
```
hereditary spherocytosis (HS)
thalassemia
sickle cell disease
G6PD
Lead poisoning
```
39
Hereditary Spherocytosis (HS)
red cell membrane defect
hemolytic anemia (jaundice, SPLENOMEGALY, gallstones)
Spherocytes*
Increased osmotic fragility*
40
Tx for HS
supportive +/- RBC transfusion
| SPLENECTOMY
41
Test for HS
osmotic fragility test
42
Thalassemia
alpha or beta
related to # of gene deletions
microcytic, hypochromic anemia
IRON OVERLOAD
43
Dx of thalassemia
HgB electrophoresis
44
Tx for thalassemia
supportive +/- RBC transfusion
Iron monitoring + chelation
splectomy may help
HSCT (severe beta-thal)
45
Sickle Cell disease sx
```
Sickle-shaped RBC when deoxygenated
Vaso-occlusion that leads to pain!
chronic hemolysis
splenomegaly
splenic infarcts (functional asplenia)
Increased risk of bacterial sepsis
may see growth failure and delayed puberty
```
46
Dx for sickle cell disease
HgB electrophoresis shows HbS
Howell-jolly bodies; target cells on peripheral smear
47
Tx of sickle cell
avoid precipitating factors
supportive
hydroxyurea*** - depress bone marrow function; used to decrease incidence of pain crises
Stem cell transplant
48
G6PD deficiency
red cell enzyme defect that causes hemolytic anemia
x-linked recessive
african, mediterranean, asian
episodic hemolysis at times of exposure to:
- oxidant stress of infection
- certain drugs/food substances
49
Clinical manifestations of G6PD deficiency
neonatal jaundice, hyperbilirubinemia
| episodic hemolysis: pallor, jaundice, hemoglobinuria
50
Lab findings of G6PD
peripheral smear: rate bites; heinz bodies (denatured Hgb)
51
Heinz bodies
G6PD
52
Tx for G6PD
supportive
| avoid certain foods/drugs known to trigger hemolysis
53
Etiology of lead poisoning
older home w/ lead pain
54
Sx of lead poisoning
anemia that is mild, hemolytic and normocytic
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Dx of lead poisoning
basophilic stippling
56
Tx for lead poisoning
chelation
57
Congenital erythrocytosis aka
familial polycythemia
58
What is familial polycythemia?
only RBC affected
| increased HgB as high as 27 g/dL
59
Sx of polycythemia
plethora and splenomegaly
| h/a, lethargy
60
Tx for familial polycythemia
phlebotomy
61
Secondary polycythemia cause
occurs in response to hypoexmia
- cyanotic congenital heart disease
- chronic pulmonary disease (CF)
62
Tx of secondary polycythemia
correct underlying disorder
| phlebotomy when indicated
63
Tests for bleeding disorders
```
CBC
peripheral smear
PT/INT, aPTT
+/- bleeding time
Platelet count (N: 150k-400k)
```
64
Risk of spontaneous bleeding platelet level
<20k
65
PT (prothrombin time)
extrinsic and common pathway
| I, II, V, VII*, X + TF
66
PTT/aPTT (activated partial thromboplastin time)
intrinsic and common
| I, II, V, VIII*, IX*, X, XI*, XII
67
Common pathway factors
I, II, V, X
68
intrinsic factors
VIII, IX, XI, XII
69
Extrinsic factors
VII and TF
70
Prothrombin
II
71
Thrombin
IIa
72
Fibrinogen
I
73
INR
more accurate reflection of PT
| used to monitor warfarin
74
Bleeding time
measure of time for hemostasis
screen test for platelet dysfunction
prolonged in platelet disorder (von Willebrand disease) and severe thrombocytopenia
75
most common bleeding disorder of childhood
idiopathic thrombocytopenic purpura (ITP)
76
ITP epidemiology
```
2-5 yo
often follows infection w/viruses
immune-mediated
90% have spontaneou remission
10-20% chronic
```
77
Pathophys behind ITP
immune-mediated attac against its own platelets (autoantibody bind platelet--> platelets phagocytized primarily by splenic macrophages --> decreased platelet life span)
78
Clinical manifestations of ITP
petechiae
ecchymosis
epistaxis
79
Lab findings for ITP
thrombocytopenia
normal WBC
normal Hgb (unless hemorrhage)
PT and aPTT are normal
80
Dx of ITP
exclusion of others
81
Tx for ITP
```
observation in asymptomatiic children
avoid medications that compromise platelet function
bleeding precautions
PREDNISONE
IVIG
Splenectomy
```
82
Inherited bleeding disorders
Von Willebrand disease
| Hemophilia
83
Most common inherited bleeding disorder
Von Willebrand Disease
84
von willebrand disease
auto dominant
M=F
decrease in the level or impairment in the action of vWF
85
Most common type of von willebrand disease
Type 1
86
vWF
bind to factor VIII and is a cofactor for platelet adhesion to the endothelium
87
Clinical presentation of VWD
prolonged bleeding from mucosal surfaces (epistaxis, menorrhagia, GI)
easy bruising
88
Lab findings for VWD
normal PT
prolonged or normal aPTT
normal or decreased vWF
PROLONGED BLEEDING TIME (helps differentiate from hemophilia)
89
Difference between VWD and hemophilia
VWD has prolonged bleeding time
90
Tx for VWD
desmopressin (DDAVP)
| vWF replacement therapy
91
DDAVP
causes release of vWF and factor VIII from endothelial stores
92
Hemophilia A
factor VIII deficiency (most common)
93
Hemophilia B
factor IX deficiency (Christmas disease)
94
Clinical presentation of hemophilia
bleeding from impaired hemostasis
mild: bleed in response to injury/trauma or surgery; may not be clinically apparent til later in life
severe: spontaneous bleeding, earlier age
```
bleeding can occur anywhere -- into joints and mm. is common
spontaneous hemarthrosis (severe disease) - can lead to joint destruciton if recurrent
```
95
Lab findings for hemophilia
normal platelet count, PT and bleeding time
prolonged aPTT (normal in mild disease)
normal vWF
96
Tx for hemophilia
```
DDAVP (hemo A)
factor replacement (VIII and IX)
```
97
Inherited bleeding disorders
VWD
| Hemophilia
98
Acquired bleeding disorders
Disseminated Intravascular Coagulation (DIC)
Liver Disease
Kidney Disease
99
DIC cause
triggered by event: sepsis, trauma or tissue injury, malignancies
100
What is DIC
hemorrhage and microvascular thrombosis
101
Pathophys behind DIC
triger --> widespread activation of coagulation cascade leading to microthrombi --> massive consumption of platelets, fibrin and coagulation factors --> severe bleeding
102
s/sx of DIC
shock- end organ dysfunction
diffuse bleeding tendency (hematuria, melena, purpura, petechiae; persistent oozing from punctures)
evidence of thrombotic lesion (major vessel thrombosis, purpura fulminans)
103
lab findings for DIC
decreased platelet count
prolonged aPTT and PT
decreased fibrinogen level (may be normal until late in course)
Elevated D-Dimer and fibrin degradation products (FDPs)
104
Tx for DIC
identify and treat triggering event
replacement therapy for consumptive coagulopathy
anticoagulant therapy when indicated
105
Liver synthesizes
prothrombin, fibrinogen
| Factors V, VII, IX, X, XII, XIII
106
Vitamin K dependent factors
II, VII, IX, X
107
Lab findings for liver disease/vit K def.
platelet count: normal in vitamin K deficiency; normal/low in liver disease
Prolonged PT, aPTT
108
Tx for liver disease and vit K
treat underlying condition
| vitamin K at birth
109
Inherited thrombotic disorders
Protein C def
Protein S def
antithrombin def
factor V Leiden Mutation
110
Protein C def
homo and hetero forms
| activated protein C inactivated activated factors V and VIII
111
Warfarin induced skin necrosis
associated w/ protein C def
112
Protein S def
homo and hetero forms
| Protein S is a cofactor for protein C
113
Factor V Leiden Mutation
point mutation in factor V that leads to resistance to inactivation by activated protein C
hetero and homo forms
114
Risk with factor V Leiden mutation
increased risk of VTE 2-7x
35 fold with hetero taking oral contraceptives
80 fold in homo
115
Antithrombin
inhibits thrombin
116
Clinical presentation of antithrombin def
VTE (efficiency of heparin may be diminished)
117
Tx of thrombotic disorders
anticoagulant prophylaxis
(UFH, LMWH, warfarin)
1st episode VTE - anticoag for at least 3 mo; may need longer
118
Type of vasculitis
Henoch-Schonlein Purpura (HSP)
119
most common type of small vessel vasculitis
HSP
120
Epidemiology of HSP
boys, ages 2-7
spring and fall
URI often precedes diagnosis
121
Cause of HSP
deposition of IgA immune complexes in small vessels of the skin, GI tract and kidneys
122
Clinical presentation of HSP
PALPABLE PURPURA
arthritis/arthralgias
abdominal pain
renal disease
123
Labs for HSP
```
normal/elevated platelet count
antistreptolysin O (ASO) titer elevated
serum IgA may be elevated
hemoccult +
urinalysis: hematuria, sometimes proteinuria
```
124
Tx for HSP
supportive
| prognosis generally good
