Anemia Flashcards

(210 cards)

1
Q

What is hematology?

A

Evaluation of medical conditions related to blood cells (anemia, leukemia, lymphoma, myeloma)

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2
Q

Oncology relates more to what?

A

Solid organ tumors (colon, lung, breast, prostate cancers)

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3
Q

How many RBCs are produced by the bone marrow each day in regular individuals?

A

200 billion

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4
Q

After RBCs are produced in the bone marrow, where are they released?

A

Peripheral blood

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5
Q

What do RBCs contain?

A

Hemoglobin

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6
Q

What does hemoglobin carry?

A

Oxygen to every cell in the body

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7
Q

RBC production can increase as needed in response to what?

A

Erythropoietin released from kidneys

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8
Q

Production of RBCs can be limited by what?

A

Deficient states or conditions

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9
Q

How is it determined that a patient has anemia?

A

Measuring RBCs (decreased) and Hgb concentration in the blood

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10
Q

Normal Hgb values in adult males?

A

13.5-17.5 g/dL

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11
Q

Normal Hgb values in adult females?

A

12-16 g/dL

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12
Q

Why do men have more Hgb?

A

A combo of increased androgens and lack of menses

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13
Q

Hgb values for those with anemia?

A

<12 g/dL

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14
Q

Mild anemia Hgb values?

A

10-12 g/dL

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15
Q

Moderate anemia Hgb values?

A

8-10 g/dL

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16
Q

Severe anemia Hgb values?

A

<8 g/dL

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17
Q

_____ is sensitive to fluid levels, while _____ is less sensitive

A

Hematocrit is sensitive, while Hgb is less sensitive

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18
Q

How are anemias classified?

A

Morphologic features (shape) and etiologic/pathophysiologic factors

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19
Q

What are the morphologic classes of anemia based on?

A

Size, shape, and color of RBC

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20
Q

Size variation of RBCs in anemia?

A

Normal, microcytic, macrocytic (megaloblastic)

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21
Q

What determines the color of RBCs?

A

Hgb amount

1+ to 4+ (least amount, pale) hypochromia levels

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22
Q

MCV (mean corpuscular volume) of microcytic RBC?

A

<80 femtoliters/cell

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23
Q

MCV of normocytic RBC?

A

80-100 femtoliters/cell

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24
Q

MCV of macrocytic RBC?

A

> 100 femtoliters/cell

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25
Color variations in RBCs/anemia?
Hypochromic, Normochromic, Hyperchromic
26
What is normocytic anemia?
Cells appear normal size but reduced in quantity
27
Causes of normocytic anemia?
Excessive blood loss, destruction/hemolysis of RBCs, anemia of chronic disease, aplastic anemia, drug-induced myelosuppression, increase in plasma volume
28
What is megaloblastic (macrocytic) anemia?
Large nucleated RBC precursors and elevated MCV >100fL
29
What is megaloblastic (macrocytic) anemia typically associated with?
Folic acid or Vit B12 deficiency
30
Role of RBC maturation in megaloblastic (macrocytic) anemia?
Normally size of RBCs get smaller as they mature, yet cells are larger from the cells not being able to complete maturation
31
What is microcytic anemia?
Smaller than usual RBCs, MCV <80fL (anisocytosis-variations in size, poikilocytosis-variations in shape, and hypochromic-pale color)
32
Most common cause of microcytic anemia?
Iron deficiency
33
Causes of anemia are mostly related to what?
Factors affecting normal processes of RBCs (ability to make/affect lifespan of RBCs)
34
Lack of which nutrients to make RBCs can contribute to anemia?
Iron, folic acid, Vit. B12 (cyanocobalamin)
35
Lack of which stimulus to make RBCs can contribute to anemia?
Decreased erythropoietin
36
Lack of which process/ability to make RBCs can contribute to anemia?
Impaired bone marrow function
37
What can contribute to reduced lifespan of RBCs/can contribute to anemia?
Chronic diseases, hemolysis
38
What may cause loss of RBCs/contribute to anemia?
Hemorrhage, hemolytic anemia
39
Presentation of anemia varies depending on what?
Acuity of onset and cause
40
General symptoms related with acute onset of anemia?
Tachycardia, light-headedness, breathlessness
41
General symptoms related with chronic onset of anemia?
Fatigue, headache, vertigo, faintness, cold sensitivity, pallor, loss of skin tone
42
Symptoms of acute/chronic onset of anemia could _______ depending on the individual
Overlap
43
Hx and PE to assess sx?
Level of fatigue, pallor, etc
44
Labs to identify anemia?
CBC (Hgb, HCT, platelets, WBC), RBC indices (to differentiate between micro vs macro), Reticulocyte count stool guaiac, specialty labs if needed & blood smear (# or morphology of RBCs)
45
RBC indices labs?
MCV, NL: 80-100 fL MCHC (mean corpuscular hemoglobin conc), NL: 31-37% MCH (mean corpusc hemoglobin), NL: 26-34 pg
46
Reticulocyte count normal value?
0.5-1.5% (high vs normal, expected rxn)
47
Labs to further evaluate anemia?
Serum iron, Serum ferritin, Transferrin, Total iron binding capacity (TIBC), Transferrin saturation (serum iron/TIBC), Folic acid, Vit. B12, Erythropoietin, Coombs test
48
Normal serum iron values?
50-160 mcg/dL
49
Normal serum ferritin levels?
Males: 30-300 ng/mL Females: 15-200 ng/mL
50
What is serum ferritin efficient for?
Iron deficiency dx
51
Normal values for Transferrin?
200-360 mg/dL
52
Normal TIBC values?
250-400 mcg/dL
53
Normal transferrin saturation values?
Males: 20-50% Females: 15-50%
54
Normal folic acid values?
1.8-16 ng/mL
55
Normal Vit. B12 values?
100-900 pg/mL
56
Normal erythropoietin values?
0-19 mu/mL
57
Types of coombs tests? what does this evaluate for?
Direct, indirect Tests for autoimmune hemolytic rxn
58
How to manage anemia?
Identify cause(s)/ineffective tx, determine goals/length of tx, correct causes, monitor effect during/after tx and make adjustments
59
How to correct causes of anemia?
Stop any bleeding, d/c myelosuppressive meds, replace deficient nutrients, blood transfusions, RBC growth factors (ESAs)
60
Which treatment option provides almost immediate correction of anemia?
Blood transfusions
61
When are blood transfusions used for anemia?
When clinical sx require immediate correction
62
Hgb levels when blood transfusions should be used for anemia?
Usually <8 g/dL, but every patients situation is different and there is no standard level which transfusion MUST be given
63
Use what type of blood for transfusions?
Packed RBCs
64
Aim for what Hgb conc. to resolve sx of anemia with blood transfusions?
>10 g/dL
65
Patient considerations with RBC transfusion?
Patients must consent, prohibited in some religions
66
What are the three nutrition deficiency-related anemias that can be aided with vitamin/mineral supplements?
Folic acid deficiency, Vit. B12 deficiency, Iron deficiency
67
Which drugs are erythropoiesis stimulating agents (ESA) for anemia?
Darbepoetin, Epoetin alfa, Epoetin alfa-epbx
68
What does iron deficiency anemia result from?
Negative iron balance (acute or chronic blood loss or insufficient iron intake)
69
Where is iron normally stored?
Intestinal mucosal cells and macrophages in liver, spleen, and bone
70
Only ______ ______ amounts of iron are eliminated each day
very small
71
Typical symptoms of iron deficiency anemia?
Fatigue, pallor, spooning of nails, brittle nails, cheilosis
72
RF for iron deficiency?
Premature infants, children in rapid growth periods, pregnant/lactating, chronic hemodialysis, post-gastrectomy, small bowel disease, menstruation, occult GI bleed
73
MCV labs for iron deficiency anemia?
Low (<80), small RBCs (microcytic)
74
MCH, MCHC labs for iron deficiency anemia?
Low, hypochromic
75
Serum ferritin level labs for iron deficiency anemia?
Low, <10-12 ng/mL (low iron stores)
76
Transferrin level labs for iron deficiency anemia?
High, body wants to transfer more iron to bone marrow
77
TIBC labs for iron deficiency anemia?
High (>400 mcg/dL), increased amount of binding sites for iron on transferrin
78
Transferrin saturation labs for iron deficiency anemia?
Low (<15%), less iron to transport on more transferrin available *ratio of serum iron/TIBC, saturation is low b/c less iron to bind to more transferrin
79
Goals of tx for iron deficient anemia?
Alleviate sx, correct iron deficiency, increase Hgb, prevent recurrence
80
Treatment options for iron deficiency anemia?
Oral iron supplements, parenteral supplementation, diet (meat, fish, poultry, plant sources are more difficult for body to extract iron)
81
% elemental iron and mg of elemental iron in ferrous sulfate PO iron salt?
20%, 60mg/300 or 65mg/325
82
% elemental iron and mg of elemental iron in ferrous gluconate PO iron salt?
12%, 37mg/300
83
% elemental iron and mg of elemental iron in ferrous fumarate PO iron salt?
33%, 33/100
84
% elemental iron and mg of elemental iron in polysaccharide iron complex PO iron salt?
100%, 150 total (50 as iron sumalate, 100 iron poly complex)
85
% elemental iron and mg of elemental iron in carbonyl PO iron salt?
100%, 45mg
86
% elemental iron and mg of elemental iron in ferric maltol PO iron salt?
100%, 30mg
87
% elemental iron and mg of elemental iron in ferric citrate PO iron salt?
21%, 210mg
88
New recommendations of iron dosing based on what?
Evidence that suggests lower doses are just as effective as higher, aiming to reduce pill burden, fewer side effects
89
Doses of iron supplement taken in the morning stimulate what?
Hepcidin production (regulates iron absorption) leading to dec. iron absorption for subsequent doses that day
90
Reduction of pill burden can be found by using what doses?
Once daily instead of 2-3x/day, every other day or 3x/wk (M-W-F)
91
Side effects of iron supplements are ______ dependent
dose
92
______ tablet per day is adequate iron supplementation for most pts
One
93
When to check Hgb to see how patients respond to PO iron?
Day 14 (should show >/=1g/dL increase)
94
Cost effective PO iron?
Generic brands of ferrous sulfate
95
Which PO iron supplements have the highest absorption?
Ferric fumarate, ferrous gluconate, ferrous sulfate
96
Which PO iron has lower bioavailability, and therefore may reduce amounts absorbed in overdoses?
Carbonyl iron
97
Which adjunct therapy can increase iron absorption?
Ascorbic acid (Vit. C) 100-1000mg
98
Which adjunct therapy can reduce risks or treat constipation from iron supplements?
Stool softeners (ex. Docusate 100mg BID)
99
Symptoms of acute iron toxicity?
Begin as nausea, vomiting, esophagitis, abdominal pain due to caustic action of iron to mucosal surface, can progress to hemorrhagic necrosis of GI tract, damage to heart/liver/CNS leading to multi-organ failure, coma, death
100
Treatment of acute iron toxicity?
Fluids, deferoxamine (iron chelator) which extract unabsorbed tablets from the GI tract, with whole bowel irrigation or gastric lavage
101
What is chronic iron toxicity?
Long term iron accumulation from overdose and/or too many RBC transfusions leading to liver, pancreas, and cardiac damage
102
How to manage chronic iron toxicity?
D/c iron treatments, and use deferoxamine or phlebotomy to remove excess iron
103
When to use parenteral iron?
Cases of iron malabsorption, intolerance of oral therapy, chronic non-compliance
104
Administration of iron dextran parenteral iron? What is dose determined by?
Multiple injections or infusions over days-weeks: typical dose 100mg/wk x 10wks *determined by degree of anemia
105
How to determine degree of anemia for parenteral iron dextran?
Dose (mL) = 0.0442 (desired Hgb - observed Hgb) x LBW + (0.26 x LBW)
106
Parenteral iron dextran requires a 25mg test dose to assess for what?
Anaphylaxis
107
What can parenteral sodium ferric gluconate and iron sucrose be used for?
Maintenance/prevention
108
Dosing for parenteral sodium ferric gluconate?
125mg/dose weekly for 8 doses (to replete iron, total 1g)
109
Dosing for parenteral iron sucrose?
100mg to 200mg per injection every 1-4 wks for 5-10 doses (to replete iron, total 1g)
110
Dosing for parenteral ferumoxytol (30mg/mL) iron?
Two 510mg doses separated by 3-8d *can rpt if needed after 1 month eval
111
Dosing for parenteral ferric carboxymaltose iron?
Weight based: If >/=50kg --> two 750mg doses separated by >7days If <50kg --> two 25mg/kg doses separated by >7days
112
How is parenteral ferric carboxymaltose iron given?
IV push or infusion
113
What is parenteral ferric carboxymaltose iron used for?
Treatment & may be repeated if required
114
Monitor patients for _____ minutes after doses of parenteral ferric carboxymaltose iron for what?
30 minutes for signs of hypersensitivity
115
How is parenteral ferric derisomaltose (monoferric) 100mg/mL given?
20 min infusion
116
How is parenteral ferric carboxymaltose iron dosed?
>/= 50kg --> give 1000 mg IV x1 <50kg --> give 20mg/kg IV ABW x 1 dose *may rpt doses if deficiency returns
117
What labs to check monthly for iron supplementation?
CBC and iron panel
118
With iron supplementation, expect to see an increase in _______ count in ___ days
reticulocyte count in 7 days (usually 4-5d) *d/t increased RBC synthesis
119
For any treatment option with iron supplementation, expect to see how much of an increase in Hgb?
1-2g/dL/wk increase
120
How long does iron therapy usually take to normalize labs?
3-6 months but may need to continue indefinitely to prevent reoccurrence (use lower doses in this case)
121
Side effects of iron therpy?
Nausea, abdominal discomfort, constipation or diarrhea, black stools
122
What does Vitamin B12 deficiency anemia result from?
Chronic low dietary B12 intake over years, poor absorption d/t intrinsic factor in gastric cells, contributing conditions
123
Contributing conditions to Vit. B12 deficiency anemia?
Whipple disease, Zollinger-Ellison syndrome, Tropical sprue, gastrectomy, IBD
124
Symptoms of Vit. B12 deficiency anemia?
Typical anemia sx, neuropsychiatric abnormalities, paresthesias, ataxia, memory loss
125
Lab tests for Vitamin B12 deficiency anemia?
Macrocytic cells (inc. MCV), Low Hgb, Low serum B12, Schilling test (to assess level of intrinsic factor), increased Homocysteine and methylmalonic acid (lack of B12 prevents enzymatic metabolic conversion)
126
Treatment goals of Vit. B12 deficiency anemia?
Resolve sx, increase Hgb, prevent recurrence
127
First line tx for Vit. B12 deficiency?
Cyanocobalamin 1000mcg PO daily (including those with neuro sx) *duration is indefinite & typically lifelong
128
Second line tx for Vit. B12 deficiency?
Cyanocobalamin 1000mcg IM or SC daily x 1-2wks or until acute sx subside THEN Weekly doses x 4wks or until Hgb/HCT normal THEN Monthly doses indeifintely (usually lifelong)
129
Why can PO cyanocobalamin for Vit. B12 be used in intrinsic factor deficiency?
Since alternative absorption routes exist
130
When to use parenteral cyanocobalamin for Vit. B12 deficiency?
If unable to take PO or no response after 2 weeks
131
What can mask Vit. 12 deficiency?
Tx with folic acid (therefore proper megaloblastic anemia dx is required)
132
How much Vit. B12 is delivered by one nasal spray of Nascobal?
500mcg
133
Dosing of Nascobal Vit. B12?
1 spray in one nostril/wk (only 4-8 doses/bottle)
134
When is Nascobal given for Vit. B12 deficiency?
Weekly for maintenance tx of patients who have responded to PO/IM/SC B12 tx **NOT for initial tx
135
When should Nascobal be administered for proper absorption?
1 hour before/after ingestion hot food or beverages
136
Rare adverse effects of Vit. B12 tx?
Hyperuricemia, Hypokalemia, Sodium retention (do not need to be routinely monitored unless suspicion of an issue)
137
How to monitor response to tx for Vit B12 deficiency?
Reticulocyte count should increase ~2-5d -Weekly Hgb (rise w/in 1-2wk, normalize w/in 1-2mos) -Sx should resolve w/in a week (some neuro/parasthesias can be irreversible in cases of prolonged deficiency) -After labs normalize, recheck q3-6mos
138
Which anemia is morphologically indistinct from Vit. B12 deficiency (macrocytosis/megaloblastosis)?
Folic acid deficient anemia
139
Causes of Folic acid deficient anemia?
Increased demand, poor absorption from SI, Alcoholism, use of folic acid antagonist meds (Sulfamethoxazole/trimethoprim, phenytoin)
140
Does folic acid deficient anemia cause psychiatric sx or parasthesias?
No
141
Lab work for dx of folic acid deficient anemia?
Low Hgb, increased homocysteine (normal MMA), low serum folic acid conc, low RBC folic acid conc
142
Treatment for folic acid deficient anemia?
PO folic acid 1-5mg IV/PO daily x ~4mos (1mg/d usually adequate, use higher doses for refractory cases) *maintenance dose of 0.4mg used in some pts w/ continued risk of folic acid deficiency
143
Monitoring response of tx for folic acid deficiency anemia?
Hgb and reticulocytes (should see response w/in 1-2wk, and should normalize in 2 months) *lack of response could suggest mixed-cause anemia
144
Is folic acid well tolerated?
Yes
145
Which drugs use folic acid pathway/may have altered metabolism leading to reduced serum levels and contribute to folic acid deficiency/slow response to tx?
Fosphenytoin, phenytoin, phenobarbital
146
What diseases involving inflammation can cause anemia of chronic disease?
Infections (HIV, Tb), Autimmune diseases (RA, lupus), CA, Chronic kidney disease, diabetes, IBD, UC, Chrons
147
Factors that lead to anemia of chronic disease?
Inflammation impairs proper use of stored iron to make RBCs, shortened RBC lifespan, decreased erythropoietin production, decreased sensitivity to erythropoietin
148
Characteristics of anemia of chronic disease?
Normal or elevated levels of iron, cause often uncorrectable, often compounded by tx for causative condition (hemodialysis, chemo, anti-virals)
149
Treatment options for anemia of chronic disease?
RBC transfusion, ESAs
150
RBC transfusion disadvantages?
Limited resources, immunologic concerns, expensive, short term/does not cure, infection risk, dated shelf life
151
What are ESAs?
Drugs that mimic the body's own erythropoietin produced by kidneys
152
Which ESA is a biosimilar to epoetin alfa?
Epoetin alpha-epbx
153
What kinds of anemia can darbepoetin be used for?
Myelosuppresive chemo, renal disease
154
What kinds of anemia can epoetin alfa and epoetin alpha-epbx be used for?
Myeslosuppressive chemo, renal disease, zidovudine use, reduce allogenic RBC transfusion w/ elective noncardiac/nonvascular surgery
155
What can be given with ESAs to prevent iron deficiency?
Iron supplements
156
How do ESAs work?
Mimic normal erythropoietin, circulate through vasculature to the bone marrow, bind to R's on hematopoietic stem cells and increase erythrogenesis -reticulocytes release into blood 7-10 days later, may be able to see change in Hgb after 2-6wks
157
Darbepoetin dosing?
Longer half life, less frequent dosing qwk, q2wk, q3wk, q4wk IV or SubQ Renal dose: 25mcg qwk Oncology dose: 500 mcg q3wk
158
Epoetin dosing?
3x/wk to qwk IV or SubQ Renal dose: 50-150 u/kg 3x/wk Oncology dose: 150-300 u/kg 3x/wk or 40,000u qwk
159
Criteria for considering ESA use in oncology pts?
Anemic (Hgb <10), getting RBC transfusions, getting myelosuppressive chemo (minimum 2 mos additional chemo planned)
160
When to NOT use ESAs in oncology pts?
DO NOT USE: -pts who's goal of chemo is to cure cancer -pts w/ myeloid malignancies (AML, CML) but okay in ALL or CLL lympoid leukemias -as a substitute for RBC transfusion when immediate correction needed -cancer pts receiving hormonal, biologic, radiotherapy unless also receiving myelosuppressive chemo
161
Dosing of ESAs?
All pts get same starting dose, change over time depending on pt response, goal is to use lowest effective dose to maintain lowest Hgb to reduce need for RBC transfusion and not exceed Hgb >11g/dL *no target HGb value as goal for success
162
5 dosing options for ESA once started?
Continue same dose, decrease dose, increase dose, hold dose (temporarily stop w/ potential restart), d/c drug
163
When to reduce dose of Darbe (ESA) by 40% or Epo by 25%?
(1) if Hgb increases by >/= 1g/dL w/in any 2 week period (2) Achieve Hgb at which RBC transfusion is not needed
164
When to hold ESA dose?
-if Hgb exceeds level at which RBC transfusion not needed (Hgb continued to increase pat Hgb at which dose was previously reduced) -continue to monitor pt/restart ESA at reduced dose if Hgb decreases to level that approaches Hgb that may need an RBC transfusion (Hgb which dose was previously reduced)
165
When to increase ESA dose?
if Hgb response <1 g/dL and remains <10 g/dL after: -4wks from start of epo, increase dose to 60,000u (max) -6wks from start of wkly darbe, increase dose from 2.25 mcg/kg/wk to 4.5 mcg/kg/wk (dose of 500mcg q3wks is max dose)
166
When to continue same ESA dose?
As long as patient still meets criteria to get ESA
167
When to d/c ESA dose?
If no response in Hgb or still need RBC transfusion 8wks after starting epo or 9wks after starting darbe
168
Maximum doses of EPO in renal patients?
20,000u 3x/wk
169
Maximum epoetin dose in oncology pts?
60,000u qwk
170
Maximum darbe dose in oncology pts?
500mcg q3wks
171
Warnings with ESAs?
Increased risk of death, MI, stroke, venous thromboembolism, thrombosis of vascular access, tumor progression or recurrenc
172
How to minimize risks of ESAs?
Monitor pts and adjust doses, use lowest dose needed to reduce need for RBC transfusion, follow dosing guidelines, only use ESAs in oncology pts for tx of anemia d/t myelosuppressive chemo & d/c following completion of chemo
173
When to use iron supplements with ESAs?
Check baseline serum iron in pts about to use ESAs May be needed during tx: ESAs trigger use of iron stores, risk of deficiency *monitor monthly with tx
174
How to monitor response to ESAs?
Monitor Hgb, HCT, reticulocyte count, iron panel, # of blood transfusions over time, BP, ESA dose
175
Response in Hgb and HCT with ESAs may not be seen for how long w/ renal pts?
2-6wks
176
Response in Hgb and HCT with ESAs may not be seen for how long w/ oncology pts?
4-8 wks (only ~60% respond to ESAs)
177
What is sickle cell anemia?
Group of conditions caused by genetic defects in hemoglobin, RBCs form sickle shape d/t abnormal Hgb causing hemolysis of affected RBCs
178
Basic pathophys of sickle cell anemia?
Amino acid substitution of beta polypeptide chain of Hgb that alters interactions between neighboring amino acids, leading to structural alterations
179
Most common type of abnormal Hgb resulting in sickle cells?
HGB-S (requires homozygous gene dor Hgb-S, 0.3% of black population where heterozygous are carriers/have sickle cell trait, 8% of black population)
180
Other abnormal Hgb types?
Hgb-C (3% black population) Hgb-E (Far east) Hgb-D (india, pakistan, afghanistan, iran) -Thalassemia
181
How to cells sickle?
RBCs produced w/ Hgb containing substituted amino acids --> oxidative stress + water imbalance --> Hgb molecules interact/clump together --> altered shape of Hgb changes shape of RBC cell membrane
182
How do sickled cells cause problems?
DO not flow well in capillaries, impaired circulation/RBC destruction/stasis flow ---> tissue hypoxia and end-organ damage
183
Humans who carry Hgb-S are resistant to what disease?
Malaria caused by protozoan plasmodium falciparum
184
Presentation of sickle cell anemia?
Sx appear as early as 4-6 mos of age when Hgb-F begins to decline (Hgb-F does not sickle): early sx- pain, swelling in hands/feet, splenomegaly chronic sx- anemia, fever, apllow, arthralgia, scleral icterus, abdominal pain, weakness, anorexia, fatigue, cardiomegaly, hepatomegaly, hematuria
185
Normal Hgb A is made of what?
2 alpha and 2 beta chains
186
Hgb-F is made of what?
2 alpha and 2 gamma chains
187
How to dx sickle cell anemia?
Evaluation based on H&P (pain, arthralgia in high risk individuals), peripheral blood smear w/ sickled cells, increased reticulocytes/platelets, screening of newborns to eval Hgb type
188
Acute increase in sx w/ sickle cell anemia can be triggered by what?
Infection, dehydration, hypoxia, acidosis, sudden temp change
189
What is a vaso-occlusive sickle cell crisis (MC crisis)?
RBCs obstruct BVs and impair circulation leading to ischemia/organ damage -pain in hands, feet, joints, extremities, abdomen, liver, lungs
190
What is aplastic sickle cell crisis?
Sudden decrease in RBC production w/ already shortened lifespan of RBCs = acute anemia
191
What is hemolytic sickle cell crisis?
Increased destruction of sickle cells in circulation faster than the body can make more
192
What is splenic sequestration sickle cell crisis?
RBCs trapped in spleen leading to splenomegaly/reducing amount of blood in circulation (MC in infants/young kids)
193
Extensive complications of sickle cell disease?
Acute chest syndrome, end organ damage, developmental delay and cognitive impairments in children
194
Sx of acute chest syndrome from sickle cell anemia?
Cough, dyspnea, chest pain, fever, pulmonary infiltrates
195
End organ damage affects of sickle cell anemia?
CV accidents, chronic skin ulcers, cardiomegaly, painful priapism, aseptic bone necrosis, osteomyelitis, retinal infarcts, cholelithiasis
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Tx goals for sickle cell anemia?
Dec. frequency and duration of crises, prevent/delay long term complications, improve QOL
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Supportive/Preventive tx for sickle cell anemia?
Folic acid (prevention of deficiency d/t hyper-erythropoiesis), Vaccines for Haemophilus influenza B and pneumococcus, prophylactic penicillin up to age 5 (125mg PO BID <3yrs, 250mg BID 3-5 yrs), Hydroxyurea (increases Hgb-F -does not sickle)
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How to treat complications of sickle cell anemia?
RBC transfusions in life-threatening situations (acute neurological deficits/TIA, may inc. transfusion rxns and iron overload), Hematopoietic stem cell transplants (only potentially curative tx, limited success, significant risk of toxicity, limited availability of donors)
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Management of sickle cell crises?
Hydration w/ saline based fluid (3-4L/d) *avoid overhydration, Pain management (individualized, can use opioids for mod-severe pain)
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Management of severe splenic sequestrian?
Splenectomy
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RBC transfusions for management of sickle cell?
Dilutes conc. of RBCs containing Hgb-S
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Follow up for Sickle cell?
Routine CBC, monitor crises, monitor pts on hydroxyurea for myelosuppression, monitor analgesic use (esp, opioids), counsel pts to avoid triggers
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L-glutamine tx for sickle cell?
Oral powder mixed w/ 8oz fluid or 4-6 oz food, may help restore antioxidant balance of NADH/NAD to prevent oxidative damage to cells *does not stop sickling but helps maintain cell flexibility, reduces complications *only for pts >5y/o
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Side effects of L-glutamine?
constipation, N/V, headache, abdominal pain
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Crizanlizumab tx for sickle cell anemia?
IV infusion q2wks x2, then monthly *for pts >/=16 yrs Blocks P-selectin binding (*inflammation in dz increases this) & reduces adhesion between sickled cells and WBCs w/ endothelial cells = better blood flow, dec vaso-occlusive crises)
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Potential SE of Crizanlizumab?
Infusion rxn: inc. pain, headache, fever, chills, NVD, dizziness, pruritus, SOB (antihistamines/acetaminophen given as prophylaxis) *severity dictates temporary or permanent d/c Can cause platelet clumping/interfere w/ tests to measure platelets Increased birth defects/miscarriage * do not use in pregnancy
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Voxelotor for sickle cell?
PO tablets once/day Inhibit polymerization of Hgb S & may limit RBC deformity, inhibit sickling, reduce blood viscosity clinical trials showed improved anemia, dec % of sickled cells, dec evidence of hemolysis (bilirubin, LDH) *for pts >/= 4 y/o
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Adverse effects of Voxelotor?
Hypersensitivity rxn, headache, N/D, abdominal pain, fatigue, interacts with strong CYP3A4 inhibitors or inducers, unclear impact/risk of vaso-occlusive crises
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Agents in clinical trials for sickle cell?
Inclacumab: Anti-P selectin monoclonal ab in phase III trial Rivipansel: E-selectin inhibitor in phase III trial
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CRISPR (exagamglogene autotemcel/exa-cel) for sickle cell?
CRISPR technology to inc. Hgb-F production: -hematopoietic stem cells removed from pt/modified w/ new gene before given back to pt *modified based on gene for BCL11A (protein that halts production of Hgb-F normally produces after birth to allow Hgb A to dominate) *modifying this gene allows for Hgb F to dominate, become major Hgb produced --> dec need for transfusions, dec. vaso-occlusive crises *being reviewed by FDA in 2023