HGB-op Anemia pt2

Question 1

Describe Hgb structure

Answer 1

2 alpha 2 beta chains
4 hemes (Fe+2) protoprohyrin ring

two pairs of globin chains

4 hemes - 4 chains = Hgb

Question 2

What is a Hgb-op

Answer 2

defective animo acid sequence (exchange/deletion)

Question 3

What is a thalassemia

Answer 3

depressed production of globin chains

Question 4

What are the Adult Hgbs?

Answer 4

Hgb A (2a,2b)
Hgb H2 (2a,2d)
Hgb F (2a,2g)

Question 5

Describe Hgb S
Nationalities
What defect
What happens to Hgb S
___ transforms to ____

Shape?
Occulde?

Answer 5

most common in african/middle east/greek
B chain defect
Hgb deoxynagated
B6 GLU - VALINE
Hgb S less soluble/sickles

Occlude microvasc - infarction

Question 6

What are some promoters of sickling?

Answer 6

Hypoxia
Low pH
Dec affinity for O2

Question 7

What are the two types of sickling

Who is it not found in and why?

Answer 7

resversable/irreversable

Not found in children until 6mos of age (Due to HgbF being predominant/no B chains)

Question 8

Describe sickle cell crisis
VOC (vasc-occul-crisis)

Answer 8

Inflammation - over expressed P-Selectin (adhesion mediator )on endothelial cells
Cellular clusters
Infarctions and Inc infections
COMMON CAUSE OF DEATH IN KIDS

Question 9

Describe Hem. crisis in sickle cell crisises

Answer 9

short Rbc life
decreased Hgb/Hct
jaundice

Question 10

Describe Aplastic crisis

Answer 10

Bm suppressed
unable to compensate

Question 11

Describe sequestration

Answer 11

massive pooling of rbcs in spleen

Question 12

Describe sickle cell anemia (Homozygous)

cell populations
shift?
BM
Hgbs present?

Answer 12

norm/norm/micro/hypo
sickle cells/targets
Nrbc/Stippling
NEUTROPHILIA (SHIFT)
thrombocytosis/erythrohyperplasia
HGB S
incr Hgb F
NO HGB A (no B chains)
Tube sol +

Question 13

Describe sickle cell trait Heterozygous

symptoms?
cells?

Hgb ranges?

Answer 13

generally asympt
occ. sickling with extreme hypoxia
normal rbc morphology
Tube sol +
20-40% Hgb S
>60% Hgb A
norm HgbA2/HgbF

Question 14

Describe Hgb C

Homozygous vs hetero

Answer 14

2nd most common in US
B chain defect
B6 GLU - LYSINE

Crystal cells

Homo: hemolytic anemia
micro/hypo
envelope cells
Hetero: Aysmptom

Question 15

Describe Hgb SC
most common…
diff what?
population?
disease states?
hgb?

Answer 15

most common double hetero Hgb structure
diff amino acid substance on each of 2 globin chains
25% west africa
Tube sol +
Mild sickle cell disease
vaso-occlu less common
NO HGB A
Mild/mod anemia

Question 16

Describe Hgb tube sol (sickle dex)

Reagents:

Principle

Answer 16

reagents: saponin - lyse rbc/create hgb
Sodium hydrosulfate - reducer
buffers

Hgb S is reduced (deoxy) crystalizes and creates cloud of suspension, normal Hgb clear

Question 17

Causes of False + in Hgb tube sol

Flase -?

Answer 17

+ - hyperproteinemia
hyperlipidemia
polycy
Hgb-c/hgb BARTS

• anemia <7mg hgb
  low Hgb S conc
  Rgt deterioration

Question 18

What MUST you confirm these with?

Answer 18

Hgb electrophoresis

Question 19

Breifly describe Hgb electrophoresis
Strip is made of?
pH?

Answer 19

hgb have charges/pH of medium affects this
they migrate at specific rates/helps distinguish
strip (cellulose acetate)
pH (8.4-8.6)

Question 20

T/F all Hgb that have abnormal patterns in Alkaline pH do not need to be electrophoresised at Acid pH?

Answer 20

false they do need to be electrophoresed at acidic pH with a CITRIC AGAR

Question 21

Describe newborn hgb-op screening

Answer 21

all 50 states
must use IEF on dried blood
HPLL
molecular DNA based - most effective when targeted to mutation

Question 22

List some other abnormal Hgb

Answer 22

Hgb D
Hgb G
Hgb O - arab
D-punjab
C-harlem

most have increased O2 affinity

Question 23

Describe Hgb E

Answer 23

B chain defect
resembles Thal
30% southeast asians
mild anemia/micro/target

Question 24

Describe Hgb M (unstable Hgb)

Answer 24

amino acid substitue in alpha or beta chain
iron not able to be oxidized, prevents O2 binding (-OH in place)
Pt have Metheme (Fe+3)
unable to carry O2
sample brown
HEINZE bodies