Transfusion Medicine Flashcards

1
Q

two components of blood?

A

cellular elements (RBC, WBC, plts)

plasma (soluble proteins and Abs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Blood type A

A

A antigen

Ab B in plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Blot type B

A

B antigen

Ab A in plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Blood type AB

A

AB antigens

NO abs in plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Blood type O

A

No antigens on RBC

Abs to A and B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Universal donor

A

type O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Universal recipient?

A

type AB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

There are over ___ RBC group systems and ___ blood group antigens

A

29

250

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How are RBCs broken down?

A
  1. Complement activation
  2. Activation of phagocytic cells
    - activation of coagulation
    - systemic inflammation
    - scavenge NO (free Hgb)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where are ABO Ags found? Are they soluble?

A

membrane bound

YES!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are other locations that ABO blood group antigens are found?

A

– Red cells and platelets
– Vascular endothelium
– Epithelial surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are soluble forms of ABO blood group antigens?

A

saliva, milk, urine, meconium, feces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What reactions are caused by ABO blood system incompatibilities?

A
  1. Hemolytic transfusion reactions (IgM)
  2. Solid organ transplantation (hyperacute rejection)
  3. Mild hemolytic disease fetus and newborn
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is mild hemolytic disease of the fetus/newborn?

A
  • mom is group O and baby is A, B or AB

- small percentage of IgG Abs cross placenta and hemolyze fetus’ RBCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What clinical sxs are assocaited with ABO incompatible RBC transfusions? What is the MC presenting symptom?

A
– Feelingofdread
– Flushing
– Feverandchills
– Pain at infusion site, lumbar spine and flanks
 – Chestandabdominalpain
– Nausea, vomiting
– Shock
– Dyspnea, hyperventilation, cyanosis

FEVER IS THE MOST COMMON PRESENTING SYMPTOM!!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the most important antigen associated with the Rh group?

A

D antigen (interchangable with Rh)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the most immunogenic blood group outside ABO?

A

Rh

Ab formation to Rh requires exposure to antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How are antibodies to D antigen (Rh) formed?

A

IgG Abs form AFTER exposure >

cause extravascular hemolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Can IgG Abs cross the placenta? What does this lead to?

A

YES

hemolyitic disease of the newborn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do you prevent hemolytic disease of the newborn?

A

anti-D prophylaxis with RhoGAM or Win RHO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Before RhoGAM ppx:

A

– D antigen responsible for most cases of HDFN

– 100% fatal for fetus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What clinical sxs are assocaited with increasing hemolysis from Anti‐D or anti‐ABO antibodies?

A

– Anemia
– Tachycardia
– Increased rate of blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the difference between weak D and partial D?

A
  • Weak D: Lower levels of D antigen on surface of RBC

* Partial D: Some antigens not present, causing negative screening results

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When are weak and partial D results (essential giving a false negative D Ag test) important?

A

Donor center

OB pts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Of the 25 Kell antigens which ones are most important?
K Kell | k Cellano
26
What is the most potent immunogen after ABO, RH?
K **kell system alloatibodies also imprt because they can lead to immediate/delayed hemolysis
27
How does the Kell system cause HDFN? What % cause severe fetal anemia?
- Kell Ag is expressed on the placenta. Ab binds causing suppression of erytropoiesis. - cause about 1-% of severe fetal anemia since use of RhIg
28
What is the McLeod phenotype?
XK protein or KX antigen system that consists of ONE antigen : XK on X chromosome
29
What is the mcleod phenotype?
(XK null, decrease in Kell as well) results from major deletions and point mutations in XK gene leading to decrased Kell antigen on RBCs BRAIN, BLOOD, PNS – Acanthocytosis–3%to40% (alteration in lipid content) – Neuromuscular disease. Weakness, areflexia in ankles and arms. – Central nervous system. • Chorea ‐ Hyperkinesias (fifth decade) limb chorea, • Basal ganglia degeneration (caudate, putamen) on CT and MRI
30
Due to chromosome placement there is an association between the McLEOD phenotype and ....
CGD
31
If you have a McLEOD pt you should...
encourage them to store autologous units of blood. If they form an antibody to XK, they will not be able to find a compatible unit in the future.
32
What antigens are associated with the Kidd blood group?
Jka, Jkb, Jk3(Jkab)
33
Kidd blood group is famous for...
disappearing and reappearing
34
Kidd blood group can cause...
ROARING delayed hemolytic transfusion reactions with AMENESTIC response and intravascular hemolysis (Increased IgG with secondary response)
35
What six angtigens (three impt) are associated with the duffy blood group?
Fya, Fyb, Fy3 (Fyab)
36
Antibodies to the Duffy "antigens" cause...
mild to severe transfusion reactions
37
Duffy Ags are less common in what populatioN? why is this impt?
• Duffy antigens are less common in African American population. – Duffy antigen is the receptor for Plasmodium vivax • This becomes important with sickle cell patients b/c tehy can develop Abs to duffy and Kidd antigens and it can be hard to find antigen negative units
38
what is the P antigen group?
* P is receptor for parvovirus B19 * Autoantibodies can develop against P‐antigen, causing Paroxysmal Cold Hemoglobinuria (PCH) * Antibodies bind in the extremities (COLD‐30 C) and activate complement in the CORE (warm‐ 37 C). * Complement causes hemolysis.
39
How does PCH present in adults vs children?
• Adults‐originallydescribedinassociationwith tertiary syphilis • Children–Usuallyfollowingaviralinfectionor vaccination. – Rarely paroxysmal, precipitated by cold, not necessarily hemoglobinuric – Children present with acute anemia following viral infection.
40
HOw do you diagnose PCH?
donald landsteiner test
41
How do you conduct the donald landsteiner test?
* Three tubes with patient’s whole blood * Tube 1: Incubate at 0 C * Tube 2: Incubate at 37 C * Tube 3: Incubate at 0 C, then move to 37 C.
42
What are L I and i antigens and what are they associated with?
* Autoantibodies against I and i develop after illnesses and cause hemolysis * Anti‐I associated with mycoplasma pneumonia‐ adults * Anti‐i associated with mononucleosis‐ pediatric
43
Why do we type?
determine ABO
44
why do we screen?
look for Abs against clinically impt RBC ags (kidd, kell, Rh)
45
How does the type and screen work?
• First do Blood Typing: Identify patient’s blood type with 2 tests: – FRONT type: Mix patient’s RBCs with anti‐A and anti‐B monoclonal antibodies – BACK type: Mix patient’s plasma with known RBCs • Since anti‐A and anti‐B are IgM, IMMEDIATE agglutination occurs • Also check Rh (D antigen) in ‘front reaction’
46
How do you perform the screening test?
With INDIRECT antiglobulin test
47
What is a cross match?
you take patients plasma and donors RBC... NO agglut - XMcompatible Agglu - XM incompatible
48
What is an electronic cross match?
• No History of Unexpected Antibodies • Current Negative Antibody Screen (q72 hours) • With Electronic Cross Match, Blood is Ready Immediately • Continues to be a small risk that patient has an antibody against a rare antigen
49
DAT vs IAT?
DAT looks for Ab bound to surface of RBC (ADD ABS to bind to Abs) IAT looks for Ab in PLASMA
50
Whole blood after a soft spin can be split into...
packed RBCS and platelet rich plasma
51
Platelet rich plasma can be HEAVY spun down to...
plt concentrate FFP Cryo
52
what volume is in a unit of RBCs?
``` Volume: 250‐350 ml – RBC = 200‐250 ml – Plasma=<50ml – 200‐250 mg Iron – Final hematocrit approximately 55‐60% – Leukoreduced ```
53
What is hte effect of 1u transfusion?
– Hematocrit increase = 3% | – Hemoglobin increase = 1 g/dL
54
What is the universal type of blood to be transfused?
O-
55
Why do we give transfusions?
to correct anemia and increase O2 delivery
56
if you have no comorbidities when are transfusions indicated?
Hgb = 7
57
if you ahve co morbidities when are transfusions indicated?
Hgb > 7 (use 8-10) ``` – Cardiac Disease – Tachycardia – Respiratory Failure – Bone Marrow Failure – Hematologic Disease – Cerebrovascular Disease ```
58
When do we transfuse neonates?
Hgb <13
59
When do we transfuse pts with cyanotic heart disease?
Hgb <13
60
What is in a FFP unit?
Volume: 200‐250 ml – 400 mg fibrinogen – 1 unit/ml all coagulation factors – Factor 7 has shortest half life = 4 hours
61
What is the difference between FFP and FP24?
– FFP must be frozen within 8 hours – If frozen with 24 hours = FP24 • FP24 contains less Factor 5, Factor 8, Protein S and Protein C
62
What are indications for plasma transfusion?
* INR >1.5 * PTT > 45” used to increase FACTORS!
63
What dose of plasma do you give?
– 10‐20 ml/kg – 2 units will should increase factor levels by 20‐30% in 70 kg person
64
What can be used for emergent reversal of warfarin?
better to use vit K if time permits
65
What is a single donor platelet unit and the volume?
6 whole blood derived units | • Volume: ~300 ml – 150 mg fibrinogen – Leukoreduced
66
1SDP unit should increase plt count by...
24-40,000 If pt is not bumping they are refractory to plts
67
What platelt count is sufficient to maintain vascular integrity? How many plts are consumed each day to repair the microvasculature?
5000 7000
68
What are the indications for platelets for normal pts, mucosal bleed, active bleeding, infants, neuro/optho surgery?
Transfuseplatelets: – <10,000 for normal patients – <20,000 for mucosal bleed – <50,000 for active bleeding, surgery, invasive procedure – <50,000 for infant < 1 month old – <100,000 for neuro or ophthalmologic surgery Platelet count = 5000/ul has been shown to be minimum required for maintenance of endothelial integrity
69
What volume of cryo to we give peopole and what does it contain?
``` • Volume: 15 ml – Usually pools of 5 or 10 are released at once • Contents: – ~250 mg fibrinogen – Factor VIII – Von Willebrand’s Factor – Factor XIII – Fibronectin ```
70
What is the indication for cryo?
Mainly fibrinogen deficiency
71
What is leukoreduction and why do we do it?
• Reduces the number of leukocytes present in RBC and platelet units. This reduces: – Febrile non‐hemolytic transfusion reactions • WBCs produce cytokines which cause febrile reactions – Alloimmunization to HLA antigens • Fairview uses 100% leukoreduced blood products
72
What does irradiation do?
– Disables Lymphocytes. Prevents TA‐GVHD – Does not compromise O2 Carrying Capacity – Increases Potassium level
73
If a patient has compromised T cell fxn, transfusion of donor lymphoctyes can cause?
‘Transfusion‐Associated Graft vs Host Disease’ (TA‐GVHD) • Nearly 100% mortality from bone marrow aplasia. – Death within 21 days of transfusion
74
What are signs/sxs of a transfusion reaction?
•Fever = 1C or 2F increase •Chills, rigors •Pain: infusion site, flank pain, back pain, chest pain, proximal extremity pain, headache •Respiratory: tachypnea, dyspnea, wheezing, rales, chest tightness, pulmonary edema, hoarseness, stridor •Cardiovascular: hypotension, hypertension, tachycardia, bradycardia, jugular venous distension, arrhythmia, shock •Cutaneous: pruritus, hives (urticaria), erythema, flushing, jaundice, pallor, cyanosis, petechia, purpura •GI: nausea, vomiting, diarrhea •Urinary: red urine (hemaglobinuria) •Heme: bleeding, oozing, coagulopathy
75
what do you do if you suspect an acute transfusion reaction?
• STOPthetransfusionimmediately! • KeeptheIVlineopen. • Administerfluidsandothermedicationsas necessary to manage clinical symptoms. • ReportthereactiontotheBloodBank • Returnunusedportionofunitwithinfusionsetto the Blood Bank. • Send additional specimens as necessary: – Purple top tube (EDTA) – Red top tube (clot tube) – Sample of first urine – Others as necessary: blood cultures, bilirubin, LDH
76
What does the blood bank do if you report a transfusion reactioN?
• Clericalcheck:confirmintendedunitwas transfused to intended patient • RepeatABObloodtypeandscreenforRBC antibodies • Directantiglobulintest(DAT):testforantibodies on RBC • Checkserumcolor(pink-redforhemolysis) – Compare to pre transfusion – Detects 2.5 to 5mL of hemolysis • Otherthingssometimesperformed – Repeat antibody screen – Gram stain and culture unit – Tests for hemolysis: LDH, bilirubin, haptoglobin,
77
What are non infectious complictions of tranfusioN?
* Allergic * HemolyticTransfusionReaction * Febrile, Non-hemolytic * TRALI * TACO * Post-TransfusionPurpura * TA-GVHD * Alloimmunization
78
Case 1 55 year old female with breast cancer who is undergoing chemotherapy. Her platelet count is 8,000 and you decide to transfuse her platelets prior to having a bone marrow biopsy. Five minutes after starting the transfusion, she feels itchy. The nurse notices red raised lesions forming on her arms and face. The transfusion is stopped and you are called to the room. When you arrive, the patient is having trouble breathing (you can hear her wheezing across the room) and is becoming hypotensive. What is your diagnosis?
Allergic Transfusion reaction - 1-3% of transfusions - hypersensitivity to plasma proteins - cause unkown - mild rxn (hives) - treat with benadryl and possibly steroids - if the reaction is only a MILD allergeci reaction and pt responds to therapy this is the ONLY time a transfusion can be restarted
79
What are known causes of alelrgic reactions?
1. IgA def (consider in pt w/ h/o severe allergic rxn to blood products, recurrent infections, atopy, asthma, ecema) 2. passively transfused alelrgens (peanuts) 3. coincidental expsoure to anagtigen
80
Anaphylactic reactions are most common in what type of transfusion?
platelets > plasma > RBC
81
most severe anaphylactic leads to...
``` hypotension uriticaria bronchospasm wheezing local edema anxiety abdominal distress ```
82
how do you tx anaphylaxis?
trendelenburg epi antihistamines, steroids, beta 2 ag
83
what are anaphylactoid reactions?
like anaphylactic but diff mechanism reactions associated w/ ACE inhibitors? – Flushing and hypotension – Historically associated with negatively charged bedside leukoreduction filters – Due to accumulation of BRADYKININ
84
Case 2 46 year old male with a GI bleed. He has a hemoglobin of 6.3g/dL, tachycardia, and feels uncomfortable. You decide to transfuse 1 units of RBC to increase his hemoglobin above 7g/dL. After 50mL of blood, he is hypotensive, feels anxious, complains of low back pain, is becoming febrile, and red urine is noted to becoming from the patient’s Foley catheter. What do you do first? What is causing the patient’s symptoms?
You stop the transfusion immediately - increases survivability. He continues to become unstable and you notice that he is starting to ooze around his IV catheter. While you are examining the patient, you notice that the unit bag tag has another patient’s name on it. this is a hemolytic transfusion reaction!! DIC!!
85
What is a hemolytic transfusion reaction and what causes it?
Occurs w/in 4 hrs of transfusion Due to the presence of preformed Ab if pt is transfusing RBC, plasma or plts Ab coated RBC activates the complement system> hemolysis (intravascular and the cytokin storm> DIC@
86
what are s/s of HTR?
* Fever–themostcommonsymptomofaHTR, but more frequently is due to other causes * Red urine (hemoglobinuria), red plasma (free hemoglobin) * Hypotension,shock * Severeflankpain * Urticaria,hives,flushing * Chesttightness,“senseofimpendingdoom” * DIC,oozing, * Vomiting,diarrhea
87
What is a delayed hemolytic transfusion reaction (DHTR) and when does it occur?
Typically occur 5-14 days to weeks after a RBC transfusion – Formation of a new antibody – Amnestic response may occur earlier with some antibodies, especially the Kidd blood group – Jka, Jkb Ab is usually undetectable on screen prior to transfusion
88
What are signs of a DHTR?
– Unexplained drop in hemoglobin – Unexplained rise in unconjugated bilirubin (jaundice) – Positive DAT (abs bound to RBC) ** If occurs without symptoms = delayed serological reaction
89
Case 3 17 year old female undergoing stem cell transplant for myeloid leukemia. While receiving a platelet transfusion she develops chills/rigors and her temperature rises from 98.6F to 102.0 F. You stop the transfusion and initiate a transfusion reaction. The work up in the Blood Bank shows a clerical check is OK, there is no evidence of hemolysis, and a gram stain on the unit is negative. What is your diagnosis?
febrile nonhemolytic trasnfusion reaction
90
What are s/s of a FNHTR?
* Most commonly reported reaction (1%) | * Fevers (>1  C or 2F) and chills/rigors
91
What is the mechanism of a FNHTR?
– Antibodies in recipient plasma to antigens on donor lymphocytes, granulocytes, and platelets. – Cytokines present in stored plasma/supernatant portion of product
92
How do you reduce hte incident of FNHTR?
Incidence reduced with leukocyte reduction of blood products
93
What is the dx and tx for FNHTR?
* Treatment: acetaminophen, meperidine for chills/rigors | * Diagnosis of exclusion, need to rule out other more serious causes of fever.
94
Case 4 78 year old frail female with heart disease, CABG, atrial fibrillation for which she is on warfarin, diabetes mellitus, hyperlipidemia, and obesity. She has been eating poorly recently. Three hours ago, her husband noticed the patient could not walk or move her left arm. Imaging confirms she has an acute hemorrhagic stroke. Her INR is 10.2 and you order 4 units of plasma to start to reverse her warfarin. During the transfusion of the 2nd unit the patient is noted to be tachypneic and her O2 sat has dropped to 80%. What is the cause of her respiratory distress?
* Transfusion Associated Circulatory Overload (TACO) •Transfusion Related Acute Lung Injury (TRALI) •Hemolytic transfusion reaction * Transfusion associated sepsis •Anaphylactic/Anaphylactoid reactions * Coincidental underlying condition: COPD, asthma, anxiety, pulmonary embolism, reaction to medication, etc.
95
What are the criteria to diagnose TRALI? RATE: • #1 cause of transfusion related fatality • 1 in 5000 transfusions
•Acute onset – within 6 hours of transfusion •Acute lung injury -Hypoxemia: PaO2/FiO2 <300 or SpO2 <90% on room air or other evidence of hypoxemia -Bilateral infiltrates on CXR -No evidence of left arterial hypertension (circulatory overload) •No other cause for acute lung injury
96
What are immune mechanisms of TRALI?
– Donor has antibodies to recipient human neutrophil antigens (HNA) or HLA on neutrophils – Soluble antibody-antigen complex activate complementneutrophil influxdamage
97
What are non-immune mechanisms of TRALI?
– Pre-existing condition activates neutrophils | – Transfused blood has accumulated lipids (biologic response modifiers) that further activate primed neutrophils
98
How do you prevent TRALI?
* Plasma containing products are more frequently implicated in TRALI * Multiparous and transfused females are the most likely to have anti-HNA or anti- HLA * Switching to male donor only plasma has reduced rates of TRALI
99
What is TACO - transfusion associated circulatory overload?
* Volume overload from transfusion * No clear definition * Occursduringorwithinseveralhoursof transfusion
100
What are sxs of TACO?
Dyspnea,respiratorydistress,orthopnea, cyanosis, tachycardia, hypertension, rales, jugular venous distension, S3 on cardiac auscultation, lower extremity edema
101
How do you tx TACO?
discontinuetransfusionandother fluids, diuretics, other supportive measures such as oxygen.
102
What increases your risk for TACO?
very young very old renal failure chronic anemia
103
what is post-transfusion purpura?
- acute severe onset of thrombocytopenia w/ plts < 10,000 - 3-10 days post transfusion - amnestic rsopnse to plt antigen on reexposure causes removal of both trasnfused and SELFL plts - RARE
104
what is tranfusion associated graft vs host disease?
Transfusion Associated Graft vs Host Disease •Engraftment of donor lymphocytes •Homozygote HLA type donor into a heterozygote recipient •Highest rate in Japan due to homogeneity of HLA types •Rash, severe diarrhea, liver abnormalities, pancytopenia (bone marrow aplasia) •4-30 days post transfusion •Almost always fatal! •Irradiation of unit prevents TA-GVHD •Very rare
105
What are indications for irradiation (i.e. pts at risk for TA- GVHD)?
* Neonates <4 months of age •Congenital immunodeficiency * All pediatric oncology patients * Stem cell transplant * Adults with acute or chronic leukemia * Adults with non-Hodgkin’s lymphoma * Hodgkin Disease * Purine analogs (e.g. fludarabine, cladribine, pentostatin) and alemtuzumab (Campath) in the past 12 months * Intrauterine transfusions •Granulocyte transfusions •Directed donations
106
what is HLA alloimmnization?
HLA (10%) – Causes poor response to platelet transfusions – Limits transplant donor options
107
What percentage of time does alloimmunization to RBC antigens occur?
• RBC antigens (1%) – Need to transfuse antigen negative RBC units – May need to find rare donor units
108
What happens if alloimmunization to plt antigens occurs?
cuases poor response to plt transfusions
109
What is alloimmunization?
defined as an immune response to foreign antigens after exposure to genetically different cells or tissues.
110
What testing is performed on donated blood?
``` • ABO and Rh typing • Screen for RBC antibodies • Tests for Hepatitis B – Anti-HbC – HBV NAT • Tests for Hepatitis C – Anti-HCV – HCV NAT (nucleic acid testing) • Tests for HIV – Anti-HIV1 and anti-HIV2 – HIV NAT • Anti-HTLV-I and HTLV-II • Serologic test for syphilis (marker of high risk behavior) • WNV (West Nile Virus) NAT • Serologic tests for CMV (some) • Bacterial testing of platelets ```
111
Case 5 15 year old female undergoing stem cell transplant for Hodgkin Disease with a platelet count of 5,000 (normal range:150,000 -300,000) and epistaxis. You order the transfusion of 1 unit of Apheresis Platelets. Within 15’ of starting the transfusion, the nurse calls you because she is developing chills and rigors, fever, and hypotension. PRE: BP 120/80, P 67, RR 20, T 98.6 POST: BP 90/50, P 104, RR 28, T102.1 What do you do first? What do you think is causing the patient’s symptoms?
Stop hte transfsuion... • A clerical check is OK. • Testing in the Blood Bank shows no evidence of hemolysis. • A gram stain of the unit shows gram positive cocci. • Cultures of patient and the unit both grow Coagulase negative Staphylococcus within 24 hours of culture.
112
What is transfusion associated sepsis?
• Platelets: – 1 in 75,100 septic transfusion reaction – 1 in 638,000 fatality • More common with platelet transfusion > store at room temperature • Symptoms:fever,hypotension,shock,nausea, vomiting, respiratory symptoms, coagulopathy
113
What are sources of contamination causing sepsis from transfusions?
* Skin commensals | * Asymptomatic bacteremia • Manufacturing
114
what are mehtods to reduce post transfusion sepsis?
``` •Donor screening •Skin preparation •Diversion of initial blood draw Bacterial detection •Culture •pH and glucose •Molecular tests for bacteria •ELISA tests for bacteria •Pathogen inactivation ```
115
Case 6 A 24 year old male presents to your clinic complaining of turning yellow, fatigue, and dark urine. He is otherwise healthy. His only hospitalization occurred 6 weeks ago after a motor vehicle accident, where his air bag deployed and he was treated for internal bleeding injuries. His recovery has been smooth since surgery and he was discharged 10 days after the accident. Why do you think he is turning yellow? On further investigation, you learn that he was transfused 2 units of RBC during surgery. You order several tests and find that he is....
Hep C POSITIVE
116
if the donation is tested, why does tranfsuion transmission still occur?
``` exposure > WINDOW 1> infectivity> VIREMIA WINDOW 2> serological detection ```
117
When does HCV ab form?
day 70
118
When does HIV Ab form?
day 22
119
How is west nile transmitted?
mosquitoes feed on birds infected w/ WNF > | infected mosquitos transmit WNV to humans and animals when taking blood meal
120
what is the incubation period for WNV?
3-14 days
121
What percent of WNV are asymptomatic?
80%
122
What percent of people develop WN fever?
20%
123
When should you consider transfusion transmitted WNV?
unexplained fever, meningitis, or encephilits after a transfusion
124
How does CMV affect infants?
– Following maternal infections, fetus becomes infected 30-40% – 5-10% develop sequelae = mental retardation, hearing loss, chorioretinitis
125
who long does the CMV seronegative window last?
6-8 weeks can still transmit virus if donor is VIREMIC but seronegative
126
How can you reduce risk of transmission of CMV?
leukoreduced = CMV safe WBC (WBC carry virus)
127
How is malaria transmitted and what is the most common type to be transmitted by transfusioN?
anopheles mosquito 14 cases in 10 years in us, 10 were p. falciparum
128
acute presentation of chagas?
chagoma, swelling of the eyelids, fever, lymphadenopathy, nausea, vomiting, diarrhea, splenomegaly
129
chronic presentation of chagas?
cardiac ( heart failure, cardiomyopathy, arrhythmia) and GI (enlarged esophagus or colon)
130
is testing of donors required for chagas?
NO!
131
Babesia
Ixodes tick >50 cases of transfuion especially in endemic areas sxs: fever, anemia, hemoglobinuria
132
risk of bacterial infection w/ transfusion?
– 1 in 5,000 – 15,000 products – 1 in 75,100 septic transfusion reaction – 1 in 638,000 fatality
133
virus most commonly found in donors?
CMV ``` then HBV HTLV HCV HIV WNV seasonally ```
134
rare parasites found in transfusions
malaria chagas babesia - Most common!
135
What are common signs and symptoms of a transfusion reaction?
fever chills hives respiratory distress
136
what is the risk of transfusion transmitted HIV?
1 in 2,135,000
137
what is the most common infectious comlication of transfusion?
bacterial
138
what are causes of respiratory distress associated with transfusioN?
``` TACO TRALI hemolytic transfuion reaction transfusion associated sepsis anaphylactic/anaphylactoid reactions ```
139
what ist he leading cause of transfusion associated fatality?
Trali