Hematology Flashcards
1
Q
normal WBC
A
5,000
2
Q
normal RBC
A
5 million
3
Q
normal platelet count
A
250,000
4
Q
hematocrit
A
% volume of blood occupied by red cells
5
Q
normal hematocrit values
A
approximately 45% to 52% for men and 37% to 48% for women.
6
Q
MCV
A
mean cell volume
7
Q
normal MCV value
A
82-98 fL
8
Q
how to calculate MCV
A
MCV = HCT/RBC
9
Q
RDW of RBCs
A
the red cell distribution width – how similar in size the RBCs are (how variable the sizes are)
10
Q
relative amounts of each white blood cell type (order from greatest to least)
A
PMN > L > Mono > Eos > Baso
11
Q
term for high white cell count
A
leukocytosis
12
Q
term for high neutrophil count
A
neutrophilia
13
Q
term for high eosinophil count
A
eosinophilia
14
Q
term for high lymphocyte count
A
lymphocytosis
15
Q
term for high RBC count
A
erythrocytosis
16
Q
clinical impact of high RBC count (erythrocytosis)
A
- hyperviscosity
- thrombosis/hypoxia
- plethoric appearace (red-faced)
17
Q
Causes of Increased RBC
A
- dehydration (less fluid = larger conc of rbc)
- hypoxia (real or imagined with increased Epo)
- Neoplastic (polycythemia vera)
18
Q
term for increased platelets
A
thrombocytosis
19
Q
-penia root
A
low count (i.e. neutropenia)
20
Q
clinical impact of anemia
A
- fatigue
- pallor (unhealthy pale appearance)
- hypoxic damage to heart or other organs
21
Q
causes of inadequate production of RBCs
A
- nutritional deficiency
- iron, folate, b12
- abnormal Hgb
- thalassemia
- infection
- parcovirus
- drug/toxin
- lead, alcohol
- marrow failure/cancerous marrow
22
Q
aplastic anemia
A
diminished or absent hematopoietic precursors in the bone marrow, usually as a result of injury to myeloid stem cell
23
Q
manifestations of aplastic anemia
A
- Anemia: pallor and fatigue
- Thrombocytopenia: purpura and mucocutaneous bleeding
- Neutropenia: infection
24
Q
bone marrow biopsy of aplastic anemia
A
hypocellular marrow with fat accumulation
25
treatment of aplastic anemia
* remove drug or toxin (if there is one)
* transfusions
* antibiotics (if infection)
* allogenic bone marrow transplant
26
causes of aplastic anemia
* Drugs (e.g. benzene, chloramphenicol, sulfonamides, chlorpromazine, propylthiouracil, alkylating agents, etc)
* Radiation exposure
* Viralinfections (e.g. EBV, hepatitis, HIV, parvovirus B19)
* Inherited Disorder (Fanconi anemia)
27
term for High RDW
anisocytosis
28
Plasma
soln of protein and electrolytes; appears some shade of yellow
29
serum
liquid soln that is left after blood or plasma cloths
30
platelets
fragments of megakaryocytes; contribute to chemical blood clotting; address sites of vascular injury
31
neutrophils
granular white blood cell; 55-70% of WBC, involved in inflammation and phagocytize foreign antigens; segmented dark nucleus; 3x bigger than RBC
32
lymphocyte
mostly in lymph nodes and spleen, less than 1% in blood, WBC responsible for immune protection; nucleus about size of RBC
33
normal values for Hemoglobin
Male: 13.5–17.5 g/dL
Female: 12.0–16.0 g/dL
34
normal RBC lifespan
120 days
35
normal PMN lifespan
1-4 days
36
normal platelet lifespan
7 days
37
Hematopoietic stem cells (HSC)
give rise to all hematopoietic cells types and self renew for the life of the animal
Stem cell --\> multipotent progenitor --\> lineage committed progenitor (myeloid progenitor or lymphoid progenitor) --\> differentiated progeny
38
allogenic bone marrow transplant
harvesting stem cells from the marrow of an individual and transfering them to another individual
39
what does a high reticulocyte count indicate?
high production of RBCs in the bone marrow
40
normal reticulocyte count
50,000 (about 1 percent of blood)
41
expected reticulocyte count in anemia
200,000 -- high reticulocyte count is expected in anemia if kidney is functioning (low oxygen causes kidney to release more epo leading to more RBC produced)
42
significance of low or normal reticulocyte count during anemia
something is wrong with RBC production; in anemia we would expect reticulocyte count to be increased
43
what does it mean if a patient has a high reticulocyte count but not anemia?
patient is losing blood and compensating by making more; double the retic count means losing blood at double the normal rate
44
conditions with microcytic anemia
**TAILS**
Thalassemia
ACD (anemia of chronic disease)
Iron deficiency
Lead poisoning
Sideroblastic
45
poikilocytosis
varied RBC shapes
46
hypochromia
pale RBC (decreased hemoglobin)
47
peripheral stained with ___ to check for reticulocytes
methylene blue
48
iron transferrin
In iron metabolism:
* Iron absorbed as Fe 3+
* Binds to transferrin in blood
* Transfer to cells
* Reduced to Fe2+
* Inserts to heme OR goes to storage
49
ferritin
storage protein for iron
Measures of ferritin levels in blood represents iron storage in body
50
hepcidin
* Liver-produced peptide; binds to channel ferroportin
* Causes iron to be sequestered (increases iron storage) -- less iron out in circulation
51
HFE gene
production gene for hepcidin
52
lab tests for iron
**Serum iron:** iron with transferrin in blood
**TIBC:** total iron binding capacity; amount of transferrin in the body
**Serum ferritin:** reflects body iron stores
53
Iron tests: differentiating iron deficiency and inflammation (anemia of chronic disease)
serum iron: decreased in both
TIBC: increasd in iron def, normal or decreased in ACD
serum ferritin: decreased in iron deficiency, increased in ACD
54
hereditary hemochromatosis
Mutations in HFE can cause diminished hepcidin release, and can eventually cause iron overload
55
factors that can lead to decreased activation of hepcidin (and then increased iron)
* iron deficiency
* HFE mutation
* ineffective erythropoiesis
* liver disease
56
factors that can lead to increased hepcidin (and decreased iron)
* inflammation
* iron excess
57
organ where excess iron is stored
liver
58
pregnancy affect on iron
pregnancy depletes iron stores
59
where is iron absorbed and what is the clinical significance of this area
iron is absorbed in the duodenum, any disease process of the small bowel (e.g. Crohn's) that affects the duodenum may compromise iron absorption
60
Clinical presentation of iron-deficiency anemia includes the following features:
* Pallor
* Fatigue
* Exertional dyspnea
* Spoon Nails (Koilonychia)
* Pica for ice (Pagophagia)
61
diagnosis of iron deficiency anemia
based on microcytic anemia & iron studies
* Decreased serum iron
* Decreased ferritin
* Increased TIBC (Total Iron Binding Capacity)
62
MCV of iron deficiency
normal MCV in early stages and microcytic later in disease
63
treatment of iron deficiency
Oral iron is the mainstay therapy for iron deficiency anemia
Blood products are generally reserved for patients who are unstable (either hypotensive due to bleeding or hypoxic due to anemia).
64
causes of iron overload
1. hereditary hemochromatosis
2. chronic ineffective erythropoiesis (decreased hepcidin); thalassemia
3. repeated transfusions
4. dietary
65
Diagnosis of iron overload
* Increased serum iron and high transferrin saturation (often \>90% in hemochromatosis)
* Very high serum ferritin (over 1000 in symptomatic patients)
* Increased liver iron (liver biopsy or MRI)
* DNA test available for hereditary HC
66
Complications of iron overload
classic triad of:
* Micronodular cirrhosis (deposition of hemosiderin in the liver)
* Diabetes mellitus (iron accumulation in pancreas and beta cell damage)
* Bronze skin pigmentation (secondary to hemosiderin and melanin deposition)
other symptoms may include:
* Arthropathy (40-60% of patients, may be the first sign of disease)
* Chondrocalcinosis
* 2nd and 3rd metacarpophalangeal (MCP) arthritis
* Dilated or restrictive cardiomyopathy (iron accumulation in the myocardium)
* Amenorrhea, impotence, hypogonadism
67
Medical treatment for hereditary hemochromatosis
repeated phlebotomy (preferred) or iron chelating agents (e.g. deferoxamine, deferiprone, deferasirox).
68
anemia of chronic disease laboratory/blood film examination findings
* MCV: Variable
* MCHC: Variable
* RDW: Variable to INCREASED
* Reticulocyte count: Usually decreased
* Free erythrocyte protoporphyrin (FEP): INCREASED
Iron study findings in the anemia of chronic disease are as follows:
* Serum ferritin: INCREASED (as an acute phase reactant, this may not be a reliable indice)
* Serum iron: DECREASED
* TIBC: DECREASED
69
Treatment for the anemia of chronic disease
involves curing or ameliorating the underlying disorder.
70
mechanism of anemia of chronic disease
Inflammation → incr hepcidin expression → Impaired release of stored iron from macrophages
lower EPO production
Direct inhibition of red cell precursors by inflammatory cytokines
Shortened red cell survival
Benefit: decreased iron available to bacteria, etc
71
low erythropoietin anemia
* Renal failure
* May be compounded by blood loss during dialysis, inflammation, decreased rbc lifespan
* Reversible with EPO injections
* Endocrine disorders
* Hypothyroidism, hypopituitarism
* Protein-calorie malnutrition 4. Right-shifted hemoglobin O2 dissociation curve
72
Megaloblastic anemias are caused by
* Vitamin B12 deficiency
* Folate deficiency
* Orotic aciduria
73
Causes of macrocytosis
– Liver disease – Alcoholism – Reticulocytosis – Hypothyroidism – Aplastic anemia – Myelodysplasia – Drugs that block DNA synthesis – B-12 and folate deficiency
74
how does vitamin B12 deficiency and folate deficiency lead to macrocytosis
there is decreased DNA synthesis in red cells. This causes red cells to undergo fewer mitotic divisions, which increases cell size (macrocytosis)
Both vitamin B12 and folate are required for the synthesis of deoxythymidine monophosphate (dTMP)
75
B12 deficiency shows high levels of \_\_\_
increased homocysteine and methylmalonate
76
folate deficiency leads to increased levels of \_\_\_
increased homocysteine
77
factors iron homeostasis depends on
1. Control of the amount of iron absorbed from the GI tract
2. Regulation of the rate of iron released to the circulation from the macrophages that are recycling senescent red cells.
3. Control of the amount of iron released to the circulation from the macrophages containing the iron storage protein ferritin
78
The hypoproliferative anemias are due to three basic mechanisms:
* An insufficient supply of iron for hemoglobin synthesis (iron deficiency or sequestration).
* Low erythropoietin levels for the degree of anemia.
* Marrow damage.
79
iron deficiency in adult men and in post-menopausal women is nearly always due to \_\_\_\_
gastrointestinal blood loss
80
Laboratory findings in vitamin B12 and folate deficiencies include:
* Hypersegmented neutrophils
* Increased serum homocysteine
* Increased serum methylmalonic acid (vitamin B12 deficiency only)
81
Pernicious anemia
autoimmune disorder characterized by a vitamin B12deficiency
trongly associated with autoimmune atrophic gastritis, in which autoantibodies against hydrogen-potassium ATPases (H+-K+-ATPases) of gastric parietal cells are formed
Parietal cells secrete intrinsic factor, which is required for vitamin B12 absorption in the terminal ileum. Thus, destruction of parietal cells leads to vitamin B12 deficiency.
82
Schilling test
a classic procedure for diagnosing pernicious anemia
* A patient may have normal intestinal absorption of vitamin B12 following administration of intrinsic factor. This raises the suspicion of pernicious anemia.
* A patient may have impaired intestinal absorption of vitamin B12 that is not corrected with administration of intrinsic factor. Potential causes of this abnormal finding include intestinal malabsorption (e.g. in Crohn disease), blind-loop syndrome, and giant tapeworm infection.
83
blood and marrow findings in B12 deficiency
* Megaloblastic anemia
* WBC and platelets may be low (pancytopenia)
* Low serum B-12 level, increased methylmalonate and homocysteine
* Marrow cellular with low G:E ratio, megaloblastic changes in rbc and granulocyte series
* Retic count not increased (ineffective erythropoiesis)
* High LDH and bilirubin due to red cell precursor breakdown in marrow (in advanced disease)
84
clinical consequences of B12 deficiency
* Loss of dorsal column function (leading to decreased vibration and position sense)
* Demyelination of the lateral corticospinal tract (leading to spasticity, weakness)
* Neural tube defects (in pregnancy)
* Glossitis
85
causes of folate deficiency
* Poor diet
* Celiac disease
* Pregnancy (increased utilization)
* Increased rbc production (chronic hemolysis – increased utilization)
* Alcoholism (poor diet, poor absorption, poor storage if liver injured)
* Anticonvulsants (phenytoin) decrease absorption
86
Clinical and laboratory findings of folate deficiency
* Megaloblastic anemia with ineffective erythropoiesis (typically less severe than advanced B-12 deficiency)
* WBC and/or platelets may be low
* No neurologic injury
* Mild maternal deficiency → neural tube defects
* Low serum folate level – RBC folate level does not provide additional useful information
* Increased serum homocysteine, normal methylmalonate
87
drug inhibition of B12
nitrous oxide
88
drug inhibition of folate
methotrexate
89
Heinz bodies
intracytoplasmic aggregates of oxidized hemoglobin that can be seen with either Prussian blue and methylene blue staining
indicate oxidative stress
90
Glucose-6-Phosphate Dehydrogenase deficiency
an acute, self-limited intravascular hemolysis due to oxidative injury to red blood cells
results in decreased formation of NADPH via the hexose-monophosphate shunt
(During states of oxidative stress NADPH is responsible for regenerating the reduced form of glutathione from its oxidized form. When glutathione is not regenerated the cell is more vulnerable to oxidative stress resulting in hemolysis.)
91
clinical complication of consuming Fava beans
ava beans can increase intracellular oxidative stress and can therefore cause an acute attack in patients with G6PD deficiency who do not have any history of infection and are not taking any medications.
92
Patients with suspected G6PD deficiency will have the following on blood smear:
* Heinz bodies are intracytoplasmic aggregates of oxidized hemoglobin that can be seen with either Prussian blue and methylene blue staining.
* Bite cells are the result of splenic macrophages attempting to phagocytose the Heinz body.
93
The Rapoport-Luebering Shunt
shunt from glycolysis pathway; Generation of 2,3-bisphosphoglycerate, the Allosteric Regulator of Hemoglobin
94
pyruvate kinase deficiency
extravascular, normocytic hemolytic anemia
The decrease in available ATP within erythrocytes leads to decreased membraneNa+/K+ ATPase activity. This leads to osmotic fragility, swelling, and hemolysis.
95
peripheral blood smear of pyruvate kinase deficiency
A peripheral blood smear in pyruvate kinase deficiency may reveal echinocytes ("Burr cells")
96
Pentose Phosphate Pathway in RBCs
An alternative but critical pathway of glucose metabolism needed to generate NADPH required to mitigate oxidative stress within the RBC.
97
All forms of hemolytic anemia are characterized by:
a shortened red cell life span (less than 120 days), elevated erythropoietin levels (increased reticulocyte count), and accumulation of hemoglobin degradation products (i.e. hemosiderin, bilirubin, etc.)
98
intravascular vs. extravascular hemolysis: definition
**Intravascular hemolysis** occurs when red cells undergo lysis inside the general circulation
**Extravascular hemolysis** occurs when red cells are phagocytosed and destroyed inside macrophages of the liver, spleen, or bone marrow
99
Intravascular hemolysis (osmolysis) occurs for some of the following reasons:
* Membrane attack complex (MAC) formation through activation of the complement cascade (paroxysmal nocturnal hemoglobinuria, acute hemolytic transfusion reaction)
* Excessive shear stress (prosthetic heart valves or microangiopathic hemolytic anemia)
* Intracellular parasitic infection (Plasmodium falciparum malaria)
100
Extravascular hemolysis (phagocytosis) occurs when macrophages are triggered to phagocytose red cells. Some of these triggers include:
* Physiologic (normal): decreased red cell deformability due to senescence or “old age”
* Intrinsic membrane defects, including spherocytosis (hereditary spherocytosis; opsonization leading to partial phagocytosis) and sickling (sickle cell disease)
* Oxidative damage
101
Laboratory findings more unique to intravascular hemolysis include:
* Decreased serum haptoglobin
* Hemoglobinuria
* Hemosiderinuria
* Increased urobilinogen in urine
102
Types of hemolytic anemia differ based on the poikilocyte produced:
* Schistocytes (helmet cells) are more common in intravascular hemolytic anemia
* Spherocytes are more common in extravascular hemolytic anemia
103
unconjugated hyperbilirubinemia (elevated indirect bilirubin) procuced in what kind of anemia?
Extravascular hemolytic anemia (and to a lesser extent, intravascular hemolytic anemia)
104
Hereditary Spherocytosis
caused by defects in red cell proteins that connect the cytoskeleton to the lipid bilayer
mutations in cytoskeletal proteins cause red cells to lose portions of their plasma membrane, thereby forcing red cells to adopt a spherical shape
105
genetics of hereditary spherocytosis
autosomal dominant
106
Red cells in patients with hereditary spherocytosis show:
* Increased mean corpuscular hemoglobin concentration (MCHC)
* Due to RBC membrane loss and dehydration
* Increased red cell distribution width (RDW)
* Due to the presence of spherocytes and normal RBCs
* Normal to decreased mean corpuscular volume (MCV)
107
osmotic fragility test
The osmotic fragility test (OFT) is used to measure erythrocyte resistance to hemolysis while being exposed to varying levels of dilution of a saline solution.
108
Conditions associated with increased osmotic fragility include the following:
* Hereditary spherocytosis
* Autoimmune spherocytosis
* Poisoning
* Severe burns
109
The following conditions are associated with decreased fragility
* Thalassemias
* Iron deficiency anemia
* Sickle cell anemia
110
diagnosing G6PD deficiency and changes through the RBC lifespan
* G-6-PD deficiency is marked by decreased stability of the enzyme
* Young RBCs have normal levels, older RBCs have lower levels and are susceptible to hemolysis
* Testing for G-6-PD levels during or immediately after a hemolytic event will yield normal results the cells with low levels have hemolyzed, leaving cells with normal levels to be measured.
* Accurate diagnosis requires waiting for recovery to normal RBC cell kinetics after removal of the oxidative stress
111
A peripheral smear of patients who have undergone splenectomy to treat hereditary spherocytosis will show:
**Howell-Jolly bodies** (basophilic nuclear remnants) and the persistence of **spherocytes**, since both are normally removed by splenic macrophages.
112
type of drug to avoid in G6PD deficiency
Drugs that increase RBC H₂O₂
113
When to Think About Hemolysis in differential
* Decrease in Hgb levels
* No source of bleeding
* No obvious reason for poor production and…
* Bone Marrow seems to be functioning well – reticulocytes are high (timing is important)
114
Labs in Hemolysis
* Reticulocytes increased (within a few days)
* Hemoglobin may be low or normal (compensated hemolysis)
* Bilirubin increased (mostly conjugated or direct)
* LDH increased – intravascular primarily
* Haptoglobin decreased (very sensitive so may be low in either situation)
* Urine heme or hemoglobin – present briefly with intravascular only
* Urine hemosiderin – present with intravascular after a couple days
115
Kidney response to oxygen (physiology)
* O2 delivered to kidney
* Kidney senses O2 levels
* peritubular interstitial cells of outer cortex release erythropoeitin (epo)
* epo acts as stimulating cytokine in erythroid cell precursor lineage
*
116
Thrombopoietin (TPO)
Regulates Platelet Production
117
what do we mean when we describe the "cellularity" of a patient's bone marrow?
Cellularity defined as % of marrow (non-bone) space consisting of hematopoietic cells (here about 60%) Normal is approximately 100 – age
118
normal bone marrow composition
About 50:50 heme cells : adipocytes in adult
Over 50% PMNs and precursors, 25% RBC and precursors, remainder lymphocytes, plasma cells, megakaryocytes
Mature cells outnumber immature cells
119
normal G:E (granulocytic:erythroid) ratio (also called myeloid:erythroid ratio)
2-3:1
120
bone marrow biopsy vs. aspirate
In bone marrow biopsy, your doctor uses a needle to withdraw a sample of the solid portion. In bone marrow aspiration, a needle is used to withdraw a sample of the fluid portion
121
composition of hemoglobin A
2 alpha and 2 beta subunits (98% of hemoglobin in adult)
122
composition of hemoglobin F
2 alpha and 2 gamma subunits
fetal hemoglobin
123
composition of hemoglobin A2
2 alpha and 2 delta subunits (2% of hemoglobin in adult)
124
composition of hemoglobin S
2 alpha and 2 beta S subunits
causes hemoglobin molecules to polymerize
125
composition of hemoglobin C
2 alpha and 2 beta C subunits
causes beta chains to crystalize
126
composition of hemoglobin H
four beta subunits
127
alpha thalassemia
Decrease in alpha subunit of hemoglobin
128
beta thalassemia
decrease in beta subunit of hemoglobin
129
hemoglobin BARTS
a tetramer of gamma (fetal) globin chains seen during the newborn period. Its presence indicates that one or more of the four genes that produce alpha globin chains are dysfunctional, causing alpha thalassemia.
130
Hemoglobinopathy
* Mutations in the amino acid sequence
* Locations in A.A. with defects -- such as affecting size (fitting) or charge
* example = sickle cell mutation
131
Sickle Cell Trait
* Heterozygous state for HbS (HbAS)
* No serious clinical consequences
* Sudden death during intensive training
* Hematuria, isosthenuria (renal papillary necrosis)
132
β+ mutations in thalassemia
characterized by diminished (but not completely absent) β-globin chain synthesis
133
β0 mutations in thalassemia
characterized by a complete absence of β-globin chain synthesis
134
β-thalassemia major alleles
([β+/β+],
[β+/β0], or
[β0/β0])
135
β-thalassemia minor alleles
([β+/β] or [β0/β])
136
Laboratory/blood film examination findings in β-thalassemia minor are as follows:
* MCV: Decreased
* RDW: Normal (differentiates β-thalassemia minor from iron deficiency anemia)
* Iron study findings in β-thalassemia minor are typically normal (differentiates β-thalassemia minor from iron deficiency anemia).
* Hemoglobin electrophoresis findings in β-thalassemia minor are as follows:
* (mildly) Decreased HbA (α2β2)
* (mildly) Elevated HbA2 (α2δ2)
* (mildly) Elevated HbF (α2γ2)
137
Laboratory/blood film examination findings in β-thalassemia major are as follows:
* MCV: Decreased
* RDW: Increased
* Indirect (unconjugated) bilirubin: Increased (from increased extravascular hemolysis)
* Codocytes ("target cells")
* Nucleated red cells (poorly hemoglobinized red cell precursors)
* Iron study findings in β-thalassemia major may reveal transfusion-related iron overload (secondary hemochromatosis).
Hemoglobin electrophoresis findings in β-thalassemia major are as follows:
* Absent (0%) HbA (α2β2)
* Increased HbA2 (α2δ2)
* (significantly) Increased HbF (α2γ2)
138
physical exam of beta thalassemia major
hepatomegaly
139
sickle cell anemia
Sickle cell anemia is a hereditary hemoglobinopathy characterized by hemolytic anemia, microvascular obstruction, and ischemic tissue damage
homozygosity for hemoglobin S (α2βS2)
140
sickle cell anemia and sickle cell trait gel electrophoresis
* In sickle cell anemia, approximately 90% of total hemoglobin is HbS. There is no HbA.
* In sickle cell trait, only approximately 40% of total hemoglobin is HbS while approximately 55% is HbA.
141
Peripheral blood smear from patients with sickle cell anemia may reveal the presence of the following poikilocytes:
* Sickle cells
* Codocytes ("target cells")
* Howell-Jolly bodies
142
what type of hemolytic anemia can sickle cell anemia produce?
extravascular hemolytic anemia
143
drug treatment for sickle cell disease
Hydroxyurea is the only widely used drug treatment for SCD. Its effectiveness is thought to stem from its ability to stimulate HbF production.
HbF has an inhibitory effect on sickling and improves the clinical course of sickle cell. HbF uses γ-globin chains (rather than β-globin) which interferes with the incorporation of sickle hemoglobin into the hemoglobin tetramer.
144
Elevated HbA2 (α2δ2) \>3.5% on gel electrophoresis is a confirmatory diagnostic test for:
β-thalassemia minor.
145
tetramer formation in alpha thalassemia
In α-thalassemia, β-globin tetramers precipitate inside mature red cells in the circulation (forming Heinz bodies that are destroyed by splenic macrophages)
146
tear drop cell / dacrocyte
bone marrow infiltration,
marrow fibrosis,
disruption with hematopoiesis in spleen
147
acanthocyte / spur cell
liver disease
states of cholesterol dysregulation
148
bite cell / degmacyte
G6PD deficiency
149
schistocyte
microangiopathic hemolytic anemias (DIC, TTP/HUS, mechanical hemolysis)
150
spherocyte
hereditary spherocytosis
drug- or infection-induced hemolytic anemia
151
target cell
HbC disease
Asplenia
liver disease
thalassemia
"HALT" said the hunter to the target
152
basophilic stippling
lead poisoning
sideroblastic anemias
153
RBC types seen in asplenia (such as post splenectomy)
target cells, nucleated RBC, Howell-Jolly bodies
154
Heinz bodies
seen in G6PD deficiency
155
Howell-Jolly bodies
seen in patients with functional hyposplenia or asplenia
(howell-jolly bodies are basophilic nuclear remnants that are normally removed from RBCs by splenic macrophages)
156
ABO chart (RBC antigen, serum, can receive blood from, can give blood to)
157
Rh factor of RBCs
* If D+ blood is given to a D- individual there will be an immunologic rxn
* A+ blood means that the individual is positive for D (Rh factor)
158
Rh hemolytic disease of the newborn
If an Rh negative mother is exposed to Rh positive blood, either by medical error or, more commonly, exposure to fetal blood during pregnancy (such as intrauterine trauma), abortion, or labor with an Rh positive infant, she may develop antibodies to Rh antigen, which can affect subsequent pregnancies. The greater the mother’s anamnestic response, the more severe the baby’s disease will be. Though any Rh group factor can cause HDN, 90% of cases are related to RhD.
159
ABO hemolytic disease of the newborn
usually occurs in type O mother with a type A or B fetus. can occur in a first pregnancy as maternal anti-A and/or anti-B IgG antibodies may be formed prior to pregnancy. does not worsen with future pregnancies. presents as mild jaundice in neonate within 24 hours of birth
160
Rhogam
medication given to mother with D- blood; has anti-D antibody and prevents mother from making anti-D response
161
Immune Hemolytic Anemia
Antibody-mediated destruction of RBC
_Types_
* Directed against foreign RBC (alloimmune) (after transfusion or from mother to fetus)
* Directed against own RBC (autoimmune)
* Drug-induced
162
Direct Antiglobulin (Coombs) Test:
test for autoimmune hemolytic anemia
detects IgG antibodies (or complement C3) on patient’s red cells
163
Indirect Antiglobulin (Coombs) Test
test for autoimmune hemolytic anemia
detects RBC IgG antibodies in patient serum
164
where are IgG antibodies cleared?
spleen
165
where are IgM antibodies cleared?
liver
166
autoimmune hemolytic anemia
antibodies directed toward the erythrocyte; can be "warm" antibodies (IgG) or "cold" antibodies (IgM)
167
autoimmune hemolytic anemia: temp at which warm and cold antibodies active
37 Celsius for warm, \<32 celsius for cold
168
autoimmune hemolytic anemia: predominant site of erythrocyte destruction in warm antibody vs cold antibody
warm: spleen
cold: liver or intravascular
169
treatment for warm antibody autoimmune hemolytic anemia
* Corticosteroids
* Splenectomy
* Immunosuppresion
* Transfusion
170
treatment for cold antibody autoimmune hemolytic anemia
* Avoid cold exposure
* Splenectomy and corticosteroids not as effective as in warm ab
171
Drug-induced Immune Hemolysis and DAT (coombs test)
* some drugs can cause positive DAT (Coombs) but not hemolysis – due to immunoglobulin adhereance to the RBCs
* DAT detects IgG on RBC surface no matter how it got there
* IgG checked for RBC specificity; might just be associating without specificity
172
clinical presentation of lead poisoning
Acute lead poisoning presents with abdominal and neurological symptoms. Anorexia, nausea, vomiting, headaches, ataxia, irritability, insomnia or seizures can be seen.
173
Peripheral smear in lead poisoning
* basophilic stippling
* Microcytic
* Sideroblast
* hypochromic anemia
174
sideroblast cell
(an iron-rich nucleated red blood cell in the bone marrow)
175
pathophysiology of lead poisoning causing anemia
The anemia results from inhibition of two enzymes involved in heme synthesis: δ-aminolevulinic acid dehydratase (ALAD), and ferrochelatase.
Heme synthesis blocked
176
this is the last hematology card
yay!
