Hematology RBC Flashcards
Pathognomonic in blood smear of G6PD
Heinz or Bite cells
AR due to chromosome breakage common in Ashkenazi Jews
Inc HBF and i Antigen
Hyperpigmentation Short stature Hypogonadism Malformation of extremities Microcephaly, mental retardation Malformations of the heart and kidneys
Pancytopenia after infancy and usually significant by 8 years
Fanconi Anemia
Microcephaly DD Cafe au lait spots Bird-like facies Micropthalmia Ptosis Strabismus, large ears VSD Horseshoe Kidney Radial abnormalities AR PANCYTOPENIA
Fanconi Anemia
Rare AR disorder Microcephaly Short stature Abnormal facie MR PANCYTOPENIA Hyperactivity, short attention span
Dubowitz Syndrome
Patients with inherited pancytopenia disorders have
chromosome fragility in metaphase preparations of PBL
Treatment for Acquired Pancytopenia
Antithymocyte Globulin
Cyclosporin
Rare congenital bone marrow failure, AD Anemia, normo and macro Reticulocytopenia Absent RBC precursors in normal BM Craniofacial abnormality 50% Skeletal anomalies GU Short stature
Congential Hypoplastic Anemia
Diamond-Blackfan Anemia
Diamnond Blackfan Anemia results from mutations jn
RPS19 gene of small 40s ribosome unit
Most common acquired red cell aplasia in children
Transient Erythroblastopenia of Childhood
Macrocytic anemia Anisocytosis, Poikilocytosis Dec retic count Neutropenia Hypersegmented neutrophils INCREASED serum ldh
Folic Acid Deficiency Anemia
FA Deficiency Anemia tx
0.5-1.0mg per day PO or IV 3-4 weeks
Maintain at 0.2mg per day if with response
Weakness Fatigue Failure to thrive Glossitis Pallor NEUROLOGIC SX Macrocytic anemia Inc urinary Methylmalonic Acid
Cobalamin Deficiency Anemia
Diagnostic for B12 deficiency
Methylmalonic acid
N 0-3.5mg/24
Tx Cobalamin Anemia
Vit B12 1.0mg parenteral oral will NOT work
Maintain with 1mg/day IM monthly
Reduction in circulating RBC mass
Anemia
Hypoxia presents with (4)
Weakness, fatigue, dyspnea
Pale conjunctiva skin
Headache, lightheadedness
Angina CAD
Markers to measure RBC mass (3)
Hb
Hct
RBC count
Anemia in males & females
<13.5 g/dl M
< 12.5 g/dl F
Microcytic anemia
MCV < 80
Normocytic
MCV 80-100
Macrocytic
MCV >100
Occur due to dec production of Hgb and extra division of cell
Microcytic anemia
Hemoglobin is composed of
Heme is composed of
Heme + Globin
Protoporphyrin + Fe
Inavailability of iron to be used for hemoglobin synthesis
Anemia of chronic disease
Any circumstance that dec production of protoporphyrin
Sideroblastic anemia
Microcytic anemia (4)
IDA
Anemia of chronic disease
Sideroblastic anemia
Thalassemia
Due to dec level of iron in the body, most common type of anemia
IDA
Most common nutritional deficiency in the world
Iron
Consumed in heme (meat derived) and nonheme (veg derived)
Iron
More readily absorbed form of iron
Heme form
Iron is absorbed in the
Duodenum
Transporter that Regulates uptake of iron to blood
Feroportin
Iron loss physiologically
Is not done by body
Decides whether iron should go into blood
Enterocyte
Iron has ability to that’s why it is always bound
Generate free radicals
transports iron and delivers it to liver and bone marrow macrophage for storage
Transferrin
Stored intracellular iron is bound to
Ferritin
For every 3 ferritin molecules,
carries iron
1
How much iron in blood
Serum iron
How many transferrin molecules in blood whether bound or not
Total Iron Binding Capacity
How many of transferrin molecules are bound by iron
Percent saturation
How many iron are in storage sites BM Macrophage and liver
Serum ferritin
Most common etiology of IDA (2)
dietary def
blood loss
In adults IDA occurs bec
PUD male
Menorrhagia or Pregnancy female
IDA in elderly bec of
Colon polyp/carcinoma
Hook worm
In neonate and infants IDA happens bec
Lack of iron in breastmilk
Poor diet
Hookworms that cause IDA
Nicator
Ancylostoma
Form of iron readily absorbed
Fe2 (ferrous) acidic form
Why can gastrectomy cause IDA
Bec gastric acid maintains acidic state fe2 hence if lost, not absorbed
Stages of Iron Def (4)
Storage iron depleted
Serum iron depleted
Normocytic anemia
Microcytic, hypochromic anemia
If ferritin goes down, TIBC
goes UP bec transferrin is released to look for Fe2 mol
Consumption of serum iron results in
Dec of percent saturation of iron
Normal percent saturation of iron
33%
Very early stage of IDA, rbcs are
before
Normocytic
Before becoming microcytic hypochromic
Clinical features of IDA (3)
Anemia
Koilonychia (spoon shaped cell)
Pica (chewing on dirt, seeking iron within dirt)
Microcytic, hypochromic anemia with inc RDW Dec ferritin Inc TIBC Dec serum iron and percent saturation Inc FEP
IDA
RDW in IDA is inc because
Of wide spectrum of size of rbc
Test to check for IDA
Free erythrocyte protoporphyrin
increased
RBCs are about the size of
Lymphocyte nucleus
Tx of IDA
Ferrous sulfate
IDA
Esophageal web
Atrophic glossitis
Dysphagia
Plummer/Vinson Syndrome
Most common type of anemia in hospitalized patients associated with chronic inflammation of cancer
Anemia of chronic disease
Chronic disease cause IDA by secreting
acute phase reactant
Acute phase reactant that sequesters iron in storage sites
Hepcidin
Hepcidin causes IDA
By limiting transfer of iron from macrophage to erythroid precursors
Hepcidin also supresses
EPO
Body releases hepcidin to
hide iron from bacteria which is needed in division except not always bacterial
Decreased available iron leading to microcytic anemia
Anemia of chronic disease
Inc ferritin Dec TIBC Dec serum iron percent saturation Inc FEP Initially normocytic then Microcytic
Anemia of chronic disease
Tx for ACD
exogenous EPO
treat underlying disease
Anemia due to defect protoporphyrin synthesis
Microcytic
Sideroblastic anemia
Final reaction of protoporphyrin synthesis is
Occurs in
Attachment of protoporphyrin to iron to make heme
Mitochondria
Rate limiting step in protoporphyrin synthesis
Succinyl coa synthesized to ALA by Aminolavulenic acid synthase
Cofactor for ALAS in protoporphyrin synthesis
B6 Pyridoxine
ALA is synthesized to porphobilinogen by
ALA dehydrogenase
Catalyzes joining of protoporphyrin with iron to become heme
Ferrochelatase
If protoporphyrin is deficient, what happens to iron
trapped in mitochondria
creating iron load around nucleus of cell
Iron laden mitochondria forming a ring around nucleus
Ringed sideroblast
In ring sideroblasts, iron is found in
mitochondria
Congential defect in sideroblastic anemia arises from
ALAS
Acquired causes of sideroblastic anemia (3)
Alcoholism
Lead poisoning
B6 Pyridoxine deficiency
Alcoholism causes sideroblastic anemia
bec it is a mitochondrial poison
Lead poisoning causes
Denaturation of ALAD and Ferrochelatase
Denaturation of ALAD and Ferrochelatase leads to
Dec production of protoporphyrin iron trapping in mitchondria
B6 Pyridoxine deficiency causes sideroblastic anemia bec
B6 is a cofactor of ALAS the rate limiting step for production of protoporphyrin
Vitamin B6 deficiency is common in patients
taking isoniazed hence sideroblastic anemia
Inc ferritin
Dec TIBC
Inc serum iron and percent saturation
Sideroblastic anemia
Sideroblastic anemia has inc serum iron bec
Rupture of iron loaded rbc leading to ingestion of macrophage of iron
Iron overloaded state
Hemochromatosis
Due to dec synthesis of globin chain of hb
Thalassemia
Dec globin lead to dec Hb resulting in
microcytic anemia
Defective globin chain
Sickle cell anemia
Carriers of thalassemia are protected against
Plasmodium falciparum
Dec production of alpha or beta globin chain
Thalassemia
A2Y2
HbF
A2B2
HbA
A2D2
HbA2
Gene deletion
Normally 4 alpha alleles on chromosome 16
alpha thalassemia
1 alpha gene deleted
asymptomatic
2 alpha genes deleted
Mild anemia with slightly inc RBC count
Worse deletion of gene
Cis more trans bec of inc risk of severe thalassemia in offspring
Asians
3 genes deleted
severe anemia
B chain forms tetramers that damage rbc
4 genes deleted
lethal in utero hydrops fetalis
Y chain forms tetramers that damage RBCs
Tetramer of gamma chains
Hemoglobin bart
Two beta genes present on
Ch 11
Gene mutation in absent beta or diminished production of B globin chain
B thalassemia
Mutation resulting in absent beta chain
Beta nau
Diminished production of b globin chain
Beta plus
Mildest form of beta thalassemia
Beta thalasemia minor B normal and B plus
Asymptomatic
Microcytic hypochromic
Target cells
Beta thalassema minor
Bleb of membrane protruding at central portion of rbc creating redness instead of pallor
target cell
Dec cytoplasm
Inc amount of membrane
Target cell
Slightly dec HbA
Inc HbA2 to 5%
Inc HbF 2%
Beta thalassemia minor
Most severe form
B nau beta nau
Severe anemia few months after birth
HbF temporarily protective
B thalassemia major
Ineffective erythropoiesis
Extravascular hemolysis bec of
A tetramer aggregation
Expansion of hematopoiesis into marrow of skull and facial bones
Extramedullary hematopoiesis with HSN
Risk of aplastic crisis with ParvoB19
Massive erythroid hyperplasia
Expansion of hematopoiesis into marrow of skull and facial bone result in
Crew cut appearance on xray
Chipmunk like face
Tx thalassemia
Chronic transfusion
Transfusion leads to inc risk of
Secondary hemochromatosis
Microcytic
Hypochromic
Target cells
Nucleated RBC
Beta thalassemia major
No HbA
Beta thalassemia major
macrocytic anemias are most commonly due to
Vit B12 and folate deficiency
Macrocytic anemia with less division of cell due to loss of precursor
> 100 MCV
Tetrahydrofolated undergoes
to participate in synthesis of DNA precursor
Methylated to enter then gives methyl to VB12
Vit B12 passes methyl to
Homocysteine
Becoming methionine
Important in transfer of methyl groups to other molecules
Methionine
Deficiency of this nutrition will not permit DNA precursor formation
Folate / Tetrahydrofolate
Folate and B12 def (3)
Megaloblastic anemia
Hypersegmented neutrophils >5 lobes
Megaloblastic change
Other causes of macrocytic anemia (3)
Alcoholism
Liver disease
Drugs (5-FU)
Difference between macrocytic anemia vs megaloblastic
Large RBCs without hypersegmented neutrophil and no megaloblastic change in rapidly dividing cells in mictocytic anemia
Folate is absorbed in
jejunum
Folate deficiency develops within
months
Methotrexate causes megaloblastic anemia by
inhibiting dihydrofolate reductase
Macrocytic rbc hypersegmented neutrophil Glossitis Dec serum folate INC serum homocysteine Normal methylmalonic acid
Folate acid def megaloblastic anemia
Inc in homocysteine in folic acid def is due to
lack of transfer of methyl group by B12 to homocysteine inc methionine
Gets converted to succinyl coa via B12 pyridoxine
Methylmalonic acid
Differentiates folic from b12 pyridoxine megalobastic anemia
Methylmalonic acid
Normal in folic acid
Vit B12 is bound to a protein produced by salivafy gland
R-binder
B12 is absorbed in
Ileum
Binds B12 secreted by parietal cell
Intrinsic factor
Less common and years to develop bec of large hepatic storage
B12 pyridoxine deficiency
Most common cause of B12 deficiency from autoimmune destruction of parietal cells leading to IF deficiency
Pernicious anemia
Other causes of VitB12 (3)
Pancreatic insufficiency (produces enzyme that cleaves b12 fr R-binder) Damage to terminal ileum by D latum or Crohn’s Dietary deficiency
Macrocytic anemia hypersegmented neutrophils
Glossitis
Subacute combined SPINAL CORD DEGENERATION
Neurologic symptoms
Dec serum b12
Inc serum homocysteine
Inc methylmalonic acid
Vit B12 Pyridoxine deficiency
Vit B12 is involved in (2)
Synthesis of DNA precursors
Transfer of methyl (conversion of methylmalonic acid to succinyl coA) inc succinyl coa in SC causes degeneration
Normocytic anemia due to (2)
Inc peripheral destruction
Underproduction
Helps distinguish etiology of normocytic anemia
Retic count
Young rbcs released from bm larger with bluish cytoplasm
Reticulocytes
Bluish hue in cytoplasm is bec of
RNA
Normal retic count
1-2%
Marrow responds to anemia by
Increasing retic count to more than 3
Retic count in anemia is falsely elevated bec
it is percentage of total blood cell
Dec in total rbc falsely elevates retic count
Correction of retic count
Multiply RC by Hct/45
> 3% RC suggests
<3% suggests
Functioning marrow
Underproduction by marrow
Anemia with good marrow response may be intra or extra
Peripheral RBC hemolysis
Extravascular hemolysis occurs in
RES spleen liver lymph mac
Intravascular hemolysis occurs in
vessels
Extravascular hemolysis findings (4)
Anemia with splenomegaly
Jaundice by unconjugated bilirubin
Inc bilirubin gallstone
Marrow hyperplasia with corrected RC of >3%
Inc hemoglobin in blood due to destruction of rbc within vessels
Intravascular hemolysis
Hemoglobin in blood is bound to
Haptoglobin and eventually lost in serum
Hemoglobinuria occurs
Due to build up of hemoglobin in the blood (hemoglobinemia)
When hemoglobin is taken up by renal tubular cells, destroyed and piled up
Hemosiderinuria days later
Hemoglobinemia
Hemoglobinuria
Hemosiderinuria
Dec serum haptoglobin
Intravascular hemolysis
Defect in myeloid stem cell resulting in absent GPI acquired rendering cell suceptible to complement destruction
Paroxysmal nocturnal hemoglobinuria
Protects rbcs from complement system (2)
Decay accelerating factor decays C3 convertase
Membrane inhibitor of reactive lysis
DAF and MIRL is connected to rbc by
By GPI ankrin protein
Shallow breathing at night with inc CO2 leads to complement activation by
acidosis
Hemoglobinuria upon waking up due to episodic intravascular hemolysis
PNH
Hemoglobinemia
Hemoglobinuria upon waking
Hemosiderinuria days after hemolysis
PNH
Screening test for PNH
Sucrose to activate complement
Confirmtatory test for PNH
Acidified serum test activate complement
Flow cytometry to detect lack CD55 (DAF)
Main cause of death in PNH
thrombosis via activation of coagulation cascase of platelets
Complications of PNH
IDA (loss of Hbg loss of iron)
10% in AML
X linked recessive disorder rendering cell susceptible to oxidative stress
G6PD Deficiency
G6PD produces to regenerate glutathione from GSSG
NADPH
Two variants of G6PD
African
Mediterranean
Mildly reduced half life of G6PD
Loss of G6PD in older cells
Lysis of older cell
African variant
Markedly reduced half life of G6PD
Earlier reduction of G6PD and hemolysis
Mediterranean
Oxidative stresses that precipitate Hb (3)
Infection,
drugs (primaquine, sulfa, dapsone)
fava beans
Precipitation of hg results in formation of
Heinz bodies
Heinz bodies (hg precipitation) removed by splenic mac result in
bite cells
Hemoglobinuria Back pain (nephrotoxic) hours after exposure to oxidative stress
G6PD deficiency
Used to screen for G6PD
Highlights precipitated hemoglobin
Heinz preparation
Enzyme studies are done for confirmation
after acute disease
Antibody mediated IgG IgM destruction of RBC
Immune hemolytic anemia
Involves extravascula hemolysis
Binds rbc in warm central body
IgG mediated
Consumption of splenic mac by membrane antibody coated RBC results in
spherocyte formation
IgG mediated is associated with (3)
SLE
Chronic lymphocytic anemia
Drugs (attaches to rbc like penicillin and antibody binds drug mem complex to remove membrane)
induce production of autoantibodies like methyldopa binding antigen in rbc
Tx of autoimmune hemolytic anemia
Cessation of drug
Steroid
IVIG -eat the injected instead of rbc buy time
Splenectomy to remove source of antibody and destruction
Intravascular hemolysis occuring in colder extremities (cold agglutinib)
IgM mediated autoimmune hemolytic disease
IgM mediated autoimmune is related to
Mycoplasma pneumoniae
Infectious mononucleosis
Used to diagnose immune hemolytic anemia
Coombs test
Confirms the presence of antibody coated RBC
Direct coombs test
Introduction of antibody against IgG to rbc
Agglutination occurs if RBCs are coated with IgG antibody
Most important test for IHA
Direct coombs test
Confirms present of antibody in serum
Indirect coombs
Anti IgG and test RBCs mixed with patient serum
Agglutination occurs if serum antibodies are present
Intravascular hemolysis from microvascular pathology
RBCs destroyed as they are passed through circulation
Microangiopathic hemolytic anemia
Develops when RBCs are sheared against platelet outgrowth in microvasculature
Schistocyte
Helmet cell
platelet thrombi from lack of ADAMS TS13
TTP
platelet microthrombi from toxin by ECOLI O15H7
HUS
Platelet plus fibrin thrombi
DIC
pregnant microangiopathic anemia in liver
HELLP
Microangiopathic hemolytic occurs in (3)
Microthrombi
Prosthetic valves
Aortic stenosis
Infection if RBC and liver with plasmodium by anopheles
Malaria
Hemolysis occurs in malaria bec of
rupture of cell during life cycle of plasmodium
Dec production of rbc with low reticulocyte count
Underproduction anemia
Causes of underproduction anemia (3)
1) causes of micro and macrocytic anemia
2) renal failure
3) damage to bone marrow precursor
Infects progenitor red cells stops EPO leading to anemia in marrow stress
Parvovirus B19
Damage to HSC
Pancytopenia
Aplastic anemia
Aplastic anemia pathognomonic
Empty marrow replaced with fat
Aplastic anemia tx (5)
Cessation of drugs Transfusion Marrow stimulating factor (EPO, GM-CSF, G-CSF) Immunosupression BMT
Pathologic process replacing bone marrow impairing hematopoiesis
Pancytopenia
Myelophthisic process
CML must be distinguished from
Leukemoid reaction
CML are (3)
1) granulocytes are LAP negative (leokocyte alkaline phosphatase for inflammation)
2) associated with inc basophil
3) exhibit t 9;22
Neoplaatic proliferation of mature myeloid cell esp rbc
All increased
Polycythemia vera
Polycythemia vera is driven by
JAK 2 KINASE MUTATION
Blurry vision headache Inc risk of venous thrombosis Flushed face due to congestion Itch after bathing Dec EPO
Polycythemia vera
Chronic, moderate to severe anemia usually manifest in infancy
Associated with normal WBC and platelets
Pure red cell aplasia as a result selective destruction of red cells in the bone marrow
Associated with increased Hemoglobin F (5-25%) and increased red cell adenosine deaminase ADA
Severe normocytic normochromic anemia
Bone marrow red cell aplasia, normal megakaryocytic and granulocytic cell lines
Diamond Blackfan Syndrome