Chapter 32 Erythrocytic Disorders

Front 1

what is the role of CD71 in erythroid precursor cells in the marrow

Back 1

CD71 is the transferrin receptor. it allows the erythroid precursor to receive iron from the recycling pool

Front 2

ascorbic acid facilitates iron absorption, while tannins inhibits it

Back 2

true

Front 3

24of with iron deficiency anemia (Hb6.3g/dL, Fe 12micrograms/dL). you advise her that the best test for monitoring a response is HEMOGLOBIN. the earliest she might check for a response is after the FIFTH DAY. after the first week the Hb can be expected to rise by 0.1 TO 0.2 G/dL per day for the next 3 weeks

Back 3

24of with iron deficiency anemia (Hb6.3g/dL, Fe 12micrograms/dL). you advise her that the best test for monitoring a response is HEMOGLOBIN. the earliest she might check for a response is after the FIFTH DAY. after the first week the Hb can be expected to rise by 0.1 TO 0.2 G/dL per day for the next 3 weeks

Front 4

how is zinc protoporphyrin (ZPP) level used to distinguish between iron deficiency and thalassemia

Back 4

ZPP is elevated (>99micrograms/dL) in iron deficiency and normal (10-99 micrograms/dL) in thalassemia

Front 5

what changes are found in marrow in megaloblastic anemia?
marrow cellularity:
number or erythroid precursors:
myeloid : erythroid ratio:

Back 5

marrow cellularity: hyperplastic
number or erythroid precursors: increased
myeloid :erythroid ratio: decreased

Front 6

what molecule serves as the cheif transport protein for cobalamin and is lacking in severe megaloblastic anemia of infancy?

Back 6

transcobalamin II (TCII)
**transcobalamin is an acute phase reactant

Front 7

describe the two types of antibodies to the intrinsic factor (IF) seen in pernicious anemia

Back 7

the blocking antibodies block the binding of cobalamin to intrinsic factor in the stomach
the binding antibodies bind to the cobalamin-IF complex, preventing it from binding to the ileal receptors in the small bowel

Front 8

39 yom immigrant from Finland* has recently been diagnosis with megaloblastic anemia. Serologic tests for autoAb are negative. what parasite can cause his anemia?

Back 8

Diphyllabothrium latum
serum cobalamin will be decreased, urine methylmalonic acid will be increased

Front 9

27 yom with celiac disease. the patient is receiving monthly injections of vit B12 and oral folate.
his serum B12 is 327pg/ml (160-950) and serum folate is 5.1ng/ml (>3.5). is red cell folate indicated?

Back 9

no. vit B12 is required for folate to gain entry into the cells, but both B12 and serum folate are within normal range, so it is unlikely that red cell folate would be abnormal; vitamin replenishment is sucessful in thei patient

Front 10

what is a likely red cell and iron studies profile in a 62yof with an acute flare of her rheumatoid arthritis?
MCV:
MCH:
RDW:
Serum Fe:
TIBC:
%iron sat:
Ferritin:
free erythrocyte porphyrin:

Back 10

MCV: nml
MCH: nml
RDW: nml
Serum Fe: low
TIBC:nml or low
%iron sat: low
Ferritin: high
free erythrocyte porphyrin:nml

Front 11

some patients taking chloramphenicol develop reticuloctopenia anemia, neutropenia and thrombocytopenia as well as morphological changes in the marrow. what is the outcome for most patients?

Back 11

transient pancytopenia occurs in about half of the patients, but only a small percentage go on to develop irreversible pancytopenia

Front 12

does serology identify the specific hepatitis virus for most cases of aplastic anemia? what are the demographics for the typical patient?

Back 12

no, most are seronegative for hep A, B, C and G. the patients are usually male under 20 years of age

Front 13

thymomas are associated with with both pure red cell aplasia and aplastic anemia

Back 13

thymomas are associated with with both pure red cell aplasia and aplastic anemia

Front 14

both alkylating agents and DNA crosslinking agents readily cause breaks in the DNA of Franconi's patients

Back 14

both alkylating agents and DNA crosslinking agents readily cause breaks in the DNA of Franconi's patients

Front 15

both Franconi's and Diamond -Blackfan patients have increased HbF

Back 15

both Franconi's and Diamond -Blackfan patients have increased HbF

Front 16

What is the most common cause of reversible acquired sideroblastic anemia?
other causes although less common?

Back 16

ethanol
antiTB drugs--isoniazid, cycloserine and pyrazinamide
lead is the key toxin

Front 17

what is the bacterial agent responsible for hemolytic anemia Oroya fever?

Back 17

Bartonella bacilliformis

Front 18

what two tests are used to diagnose congential dyseythopoieetic anemia type II(CDA-II)? give the results of each

Back 18

acidified serum hemolysis test is positive
the sucrose hemolysis test is negative
CDA-II red cells react strongly with anti-I and anti-i

Front 19

patients with hereditary spherocytosis (HS) have an increased osmotic fragility

Back 19

Front 20

12 yog whose father has HS has an osmotic fragility performed immediately on drawing her blood . the result is within the reference range but at the high (borderline increased fragility) end. a 24 hour incubation test is performed to explore this further. which patient 1 or 2 demonstrates HS?

Back 20

Front 21

several red cell membrane proteins which defend against the body's own complement system are decreased or absent in PNH. the two key proteins are CD55 and CD59. what are their functions.?

Back 21

CD55: decay accelarating factor, it anatagonizes the convertase complexes of the complement.
CD59: is a membrane inhibitor of reactive lysis (MIRL). it controls and inhibits the membrane complex (C5B-C9)

Front 22

name the three hemoglobins that are normally present in the first trimester of gestation?

Back 22

HbsGower 1, Portland, and Gower 2. these can be roughly thought of as the first attempts at Hbs A,F, ans A2, only using the zeta and epsilon chains which are analogs of the alpha, beta, delta and gamma chains

Front 23

20 month old has 8% Hb F on electrophoresis. is this diagnostic of a hemoglobinopathy

Back 23

no, about 20% of toddlers 12-24 months have HbF levels 3-10%

Front 24

after receiving primaquine, a person with which G6PD variant would be likely to have the most severe hemolysis?
variant A
variant B
Variant Mediterranean

Back 24

the mediterannean variant patient may have as little as 1% G6PD activity and is at risk for greater hemolysis than the black person with variant A, who has 5-15% activity. Variant B is the most common of the 300-plus G6PD variants and is normal

Front 25

heinz bodies may be found in the red cells in the most common red cell enzyme deficiency involving the glycolytic pathway?

Back 25

no. False. Heinz bodies are seen in pyruvate kinase deficiency

Front 26

phenotypes seen in alpha thalessemia with 1,2,3, and 4 gene deletions??

Back 26

one gene deleted- silent carrier
two genes deleted- alpha thalassemia trait
three genes deleted- Hb H disease
four genes deleted- hydrops fetalis

Front 27

what 2 hemoglobins migrate with the HbS at alkaline electrophoresis?
at acid pH these two migrate with?

Back 27

D, G (and Lepore)
A

Front 28

in cooley's anemia what is the predominant Hb?

Back 28

Hb F is the predominant Hb in the homozygotes for beta-thalassemia. in beta 0- thalessemia, Hb F can be as high as 98%. in beta+-thalessemia, a slightly less debelitating form of homozygosity for beta-thalessemia, Hb F is 60-95%

Front 29

HbA2 quantitation is most often used to identify individuals with what common hemoglobinopathy?

Back 29

beta-thalassemia trait; HbA2 levels may be up to 7%; 3.5% is usually the high end of the reference range

Front 30

contrast the result of the acid elution slide test for
Hb F in persons with hereditary persistence of fetal hemoglobin (HPFH) and thalassemia

Back 30

in HPFH, Hb F is evenly distributed among the red cells. in thalassemia and other hemoglobinopathies where Hb F is increased, the Hb F is unevenly distributed

Front 31

give the levels of the following hemoglobins in sickle cell disease
Hb SS
Hb AS
Hb C
Hb SC
Hb AC

Back 31

Hb SS: S >80%, F 1-2%, A2 2-5%
Hb AS: A 50-65%, S 35-45%, F 0 -1%, A2 2-5%
Hb C: C >90%, F 2-4%, A2 2%
Hb SC: s 50%, C <50%, F <2%, A2 2%
Hb AC: A 55%, C 40%, F <7%, A2 2%

Front 32

homozygotes for Hb D, E and G are usually asymptomatic. What laboratory result is abnormal in one of the hemoglobinopathies, giving a clue to its presence?

Back 32

Hb E is abnormal, persons with both Hb E disease and trait have low MCV. this may suggest thalassemia trait until explored more thouroughly

Front 33

after the neonatal period , Hb Bart's is seen only in what disorder?

Back 33

this is Hb H disease in which three of the four alpha-globin genes are deleted. these patients have 5-30% Hb H and just a trace of Hb Bart's as adults

Front 34

are reticulocytes preferentially destroyed in glucose-6 -phosphate dehydrogenase (G6PD) deficiency?

Back 34

no, it is the senescent red cells, with less G6PD activity to begin with, that are the greatest risk of hemolysis

Front 35

TTP?

Back 35

vWF-cleaving protease present in normal individuals cleaves the ultra-large vWF multimers which are secreted by the endothelial cells. deficiency in this protease results in failure to cleave the multimers, which are highly adhesive and induce platelet clumping throughout the circulation. the gene for coding this enzyme is ADAMTS13

Front 36

warm autoimmune hemolytic anemia is usually due to an IgG antibody. the most common subclass of IgG is ??, and ?? and ??

Back 36

IgG1, IgG2 and IgG4

Front 37

physical description of a person with Gaisbock's syndrome?

Back 37

obese male smoker, also hypertensive

Front 38

disorders of the kidney associated with inappropriate erythropoietin production

Back 38

renal tumors, especilly renal cell carcinoma. renal cysts. hydronephrosis

Front 39

explain the disparity between the percentage of patients taking methyldopa who have a positive DAT and percentage with hemolytic anemia

Back 39

in addition to causing a positive DAT in up to 1/3 of the patients taking the drug methyldopa also decreases mononuclear phagocytic activity, and this may explain the lower than expected persons with hemolysis

Front 40

double heterozygotes for the sickle cell mutation and beta-thalessemia have more Hb S than Hb A. this is useful in the distinction of Hb S/beta+- thalassemia from Hb AS. How is the distinction between Hb S disease and Hb S/beta0-thalessemia made?

Back 40

Hb S/beta0-thalessemia double heterozygotes have a lower MCV and MCH and an increased HbA2 due to their thalessemia compared to sickle cell disease

Front 41

a patient with chronic paroxysmal cold hemoglobin (PCH)...what class of immunoglobin is involved in PCH?

Back 41

biphasic igG (Donath-Landsteiner Ab)
chronic PCH is associated with congenital syphyllis