RBC DISORDERS-1 Flashcards Preview


Flashcards in RBC DISORDERS-1 Deck (43):

Hemolytic anemia; jaundice at birth


Normocytic anemia with reticulocytosis

PS: Echinocytes


1. Cause for formation of echinocytes?

2. Confirmatory test?

1. Pyruvte kinase deficiency-->chronic lack of ATP-->memnbrane damage-->echinocytes

2. RBC enzyme assay


Young African- American 

fever, cough, chest pain, and pulmonary infiltrates; secondary to infection of lungs


Lab: Hematocrit 18%, unconjugated bilirubin elevated

Peripheral smear attached

What is the genetic basis for this condition?



Point mutation in the 6th codon of beta globin leading to replacement of a glutatmate residue with a valine residue


1. Type of gallstones formed in hereditary spherocytosis

2. Why do pigmented gallstones form in this condition?

1. Pigmented gallstones 

2. Caused by increased liver conversion of excess amounts of UCB to water-soluble conjugated bilirubin (CB), which is excreted in the bile. The CB is converted back to UCB in the gallbladder, and the UCB combines with calcium to form black calcium bilirubinate stones.


Direct/ Indirect Coomb's? 

patient’s red cells are mixed with sera containing antibodies, specific for human immunoglobulin or complement.

Direct Coomb's test


How does transit time through microvascular beds affect sickling?

Transit time- spleen, BM and inflamed vascular beds- more sluggish flow areas- most involved in sickling. Vicious cycle of sickling, obstruction, hypoxia, and more sickling.


mc enzyme deficiency causing hemolysis

NCNC anemia

See attached peripheral smear

1. Diagnosis?

2. What is the trigger for formation of these cells?

3. What do the inclusions within the RBcs represent?

1. Glucose-6-Phosphate Dehydrogenase Deficiency

2. Bite cells are produced in the face of oxidant stress-Infections,Drugs- antimalarials, sulfonamides,  fava bean

3. The inclusions are Heinz bodies- represent the precipitated dentaured Hb


MCHC anemia

Increased serum iron

Increased percent saturation

increased serum ferritin

1. Diagnosis?

2. List important causes

1. Sideroblastic anemia

2. Chronic alcoholism, decreased pyridoxine, INH therapy, Lead poisoning


Direct/Indirect Coomb's ?

Direct Coomb's

In the direct Coombs test, red blood cells (RBCs) sensitized with IgG antibodies (or C3b, C3d) are agglutinated when Coombs reagent (rabbit anti-IgG antibody) is added to the test tube.


What is the major red cell hemoglobin in beta thalassemia major?



Identify the missing protein in the area marked ''?" in the image attached. 

This protein is involved in transporting ferrous iron from the cytoplasm across the basolateral enterocyte membrane




Described below is a peripheral smear appearance. Comment on the possible spleen morphology in this condition:

irreversibly sickled cells


target cells, which result from red cell dehydration

Howell-Jolly bodies+/-

Splenomegaly--> infarction-->shrinkage                               -->autosplenectomy



Enzymes inhibited by lead

Denatures ferrochelatase- inhibits incorporation of iron into protopophyrin; FEP, which is proximal to the enzyme block, is increased.

Denatures ALA dehydrase → ↑δALA

Ribonuclease is denatured- persist in the RBC, resulting in coarse basophilic stippling


Identify the missing protein in the area marked ''?" in the image attached. 

This protein is synthesized and released from the liver in response to increases in intrahepatic iron levels.



     Passage of dark urine in the morning


                         Decreased serum haptoglobin

                          Increased urinary hemoglobin

What is the underlying pathogenesis of this condition?


The condition described is Paroxysmal Nocturnal Hemoglobinuria

The pathogenesis is intravascular complement mediated lysis  due to acquired PIGA mutation


1. Possible genotypes in beta thalassemia major?

2. What do the symbols β+ and β0 mean?

1. β+/β+



2. β0absent beta -globin synthesis; β+:  reduced but detectable beta globin synthesis



Cause for aplastic crisis in sickle cell disease?

Parvovirus B19 infection-->transient cessation of erythropoiesis -->worsening of anemia


Decreased serum iron

Decreased TIBC

Increased serum ferritin

Decreased percent saturation of transferrin

Normal RDW

Anemia of chronic disease


1. Name one condition where this finding is seen?

2. What is the mechanism repsonsible for this appearance?

1. Lead poisoning

2. Lead denatures ribonuclease leading to persistence of ribosomal RNA which aggregates


Direct/ Indirect Coomb's ?

patient’s serum is tested for its ability to agglutinate commercially available red cells bearing particular defined antigens

Indirect Coomb's test


Direct/Indirect Coomb's ?

Indirect Coomb'S 

In the indirect Coombs test, IgG antibodies (e.g., anti-D) in the serum must first bind to blood group type O test RBCs added to the test tube. Addition of Coombs reagent causes the sensitized type O test RBCs to agglutinate, indicating that IgG antibodies are present in the serum


deletion of all four α-globin genes

severe pallor, generalized edema, and massive hepatosplenomegaly

Hydrops fetalis


Decreased serum iron

Increased TIBC

Decreased serum ferritin

Increased RDW

Iron deficiency anemia


Identify the missing protein in the area marked ''?" in the image attached. 

The form of iron that is in the storage pool



List 2 hematologic conditions where this appearance is seen?

Sickle cell disease

Thalassemia major


Crew cut appearance - Bone resorption and secondary new bone formation due to expansion of the bone marrow


List 3 hematologic conditions where the following cells seen in the attached peripheral smear are seen

Artificial mechanical cardiac valves

thrombotic thrombocytopenic purpura (TTP)

hemolytic-uremic syndrome (HUS)

                     disseminated intravascular coagulation




Intravascular/ extravascular hemolysis?




•Splenomegaly- due to hyperplasia of phagocytes

•Depleted serum haptoglobin

•Elevated LDH

extravascular hemolysis




colicky type of abdominal pain with constipation

Encephalopathy: edema/demyelination

Growth retardation (kids)- deposits in epiphyses

Wrist drop, foot drop, claw hand – adults

Lead line in the gums

Proximal renal tubular acidosis


List the pain/vaso-occlusive crises assoc with Sickle cell disease


1. hand foot syndrome/ dactylitis

2. Acute chest syndrome

3. Priapism

4. Stroke, Retinopathy, blindness


Intravascular/extravascular hemolysis?






•Jaundice- UCB

•Depleted serum haptoglobin

•Elevated LDH

Intravascular hemolysis


What is β-thalassemia minor or β-thalassemia trait?

Heterozygotes with one β-thalassemia gene and one normal gene (β+/β or β0/β)


1. Warm/Cold autoantibody?

IgM type

Cleared by the liver

Peripheral smear shows agglutination mainly

2. List 2 conditions where the type of  autoantibody described above is encountered

1. Cold

2. Mycoplasma, EBV, Lymphoplasmacytic lymphoma


1. Warm/Cold autoantibody?

IgG type

Primarily cleared by the spleen

Spherocytes seen on blood smear

2. List 2 conditions where the type of  autoantibody described above is encountered

3. What test is positive?

1. Warm

2. SLE, chronic lymphocytic leukemia

3. DIrect Coomb's test is positive


Why do sickle cell patients develop a sequestration crisis?

Massive entrapment of sickle RBCs -->rapid splenic enlargement -->hypovolemia, shock


How does interaction of HbS with HbF affect the degree of sickling?

HbF inhibits the polymerization of HbS  hence, infants do not become symptomatic until they reach 5 or 6 months of age, when the level of HbF normally falls


1. Condition resulting from deletion of three α-globin genes.

2. Possible clinical presentation of this condition

1. Hemoglobin H Disease

2. resembles beta thalassemia intermedia. Severe MCHC anemia but may not require regular transfusions

(refer slide 18 of RBC-Part 2)


List 1 example under each of the following causes for iron deficiency anemia:

a. blood loss-

b. increased utilization

c. decreased intake

d. decreased absorption

e. intravascular hemolysis




a. blood loss- Peptic ulcer, hookworm, colorectal cancer

b. increased utilization- menorrhagia, pregnancy, lactation, children

c. decreased intake- dietary deficiency

d. decreased absorption- celiac sprue

e. intravascular hemolysis- MAHA, PNH


mc causative orgainsm for osteomyelitis in sickle cell disease patients

Salmonella paratyphi


Cause for the following symptom:

consumption of non-foodstuffs such as clay, mud, ice 

Depletion of iron from the central nervous system- known as pica ; assoc with iron deficiency anemia


List 3 characteristic findings on peripheral smear in the hematologic condition described below: 

growth retardation

Enlarged and distorted cheekbones and other bony prominences


Electrophoresis: major red cell hemoglobin is HbF

1. microcytic hypochromic anemia

target cells

elevated retic count but less than expected for the degree of anemia




Increased MCHC

Normal MCV

Increased osmotic fragility

PS: shows small, dark-staining red cells lacking the central zone of pallor

1. Diagnosis?

2. What is the intrinsic defect in the RBC membrane?

3. Why do RBCs develop this characteristic shape?

1. Hereditary Spherocytosis

2. Spectrin deficiency (most common)

3.a.  Membrane loss occurs with age-->loss of membrane  relative to cytoplasm--> forces RBC  to assume the smallest diameter for a given volume-->spherical.

b. Membrane defect -->loss of both potassium and water, -->cellular dehydration-->spherocyte 



Special stain for hemosiderin

Prussian blue


What do the blue stained RBCs represent?

Called sideroblasts - iron trapped within mitochondria in developing RBCs


PS: mild MCHC anemia, target cells

Look at the attached electrophoretic pattern

What's your diagnosis?

(Hint: Slide 16 of RBC-2 ppt)

beta thalassemia minor

(Look up slide -16 of RBC-Part 2 to compare the electrophoretic patterns of normal individuals versus Beta thalassemia minor and major)