ANEMIA 2

A

According to the cyanmethemoglobin (HiCN) reference method, what is the specific wavelength used to measure the

absorbance of hemiglobincyanide in a spectrophotometer?

A) 540 nm

B) 450 nm

C) 580 nm

D) 630 nm

E) 500 nm

A

What is the primary cause of a falsely low hematocrit reading in microhematocrit testing due to technical error?

A) Tube leakage caused by improper tube sealing

B) Trapped plasma between packed red cells

C) Insufficient centrifugation time

D) Severe hemoconcentration

E) Patient dehydration

A

In Sahli's acid hematin method for hemoglobin determination, what dilute acid reagent is used to convert hemoglobin

into brownish-yellow acid hematin?

A) 0.1 N Hydrochloric acid (HCl)

B) 0.1 N Sulfuric acid (H2SO4)

C) 0.5 N Nitric acid (HNO3)

D) 0.1 N Acetic acid

E) 0.02 N Sodium hydroxide

A

According to the 'Rule of Three' quality control check for normocytic, normochromic RBCs, if a patient's hemoglobin is

12 g/dL, what is the expected hematocrit value?

A) 36%

B) 32%

C) 40%

D) 42%

E) 30%

A

Which erythrocyte index measures the average volume or size of individual red blood cells and is expressed in

femtoliters (fL)?

A) Mean Corpuscular Volume (MCV)

B) Mean Corpuscular Hemoglobin (MCH)

C) Mean Corpuscular Hemoglobin Concentration (MCHC)

D) Red Cell Distribution Width (RDW)

E) Reticulocyte Production Index (RPI)

A

Which underlying pathophysiologic mechanism is responsible for Megaloblastic Anemia?

A) Impaired DNA synthesis due to Vitamin B12 or Folate deficiency

B) Deficient globin chain synthesis

C) Deficient protoporphyrin synthesis

D) Reduced erythropoietin production by the kidneys

E) Autoimmune destruction of hematopoietic stem cells

A

What is the normal reference range for hematocrit in healthy adult females?

A) 36% to 46%

B) 41% to 53%

C) 49% to 61%

D) 30% to 38%

E) 52% to 62%

A

Which automated cell counter technology measures cell size based on changes in electrical resistance as cells pass

through a small aperture?

A) Electrical impedance

B) Radiofrequency conductivity

C) Optical light scatter

D) Cytochemical staining

E) Spectrophotometr

A

What is the hallmark morphological finding on the peripheral blood smear in Hereditary Spherocytosis (HS)?

A) Small, round, dense RBCs without central pallor

B) Large oval-shaped RBCs with hypersegmented neutrophils

C) Sickle-shaped erythrocytes with pointed ends

D) Hypochromic microcytes with ringed sideroblasts

E) Fragmented schistocytes and helmet cells

A

Which active ingredient in Drabkin's reagent is responsible for oxidizing hemoglobin iron to the ferric state

(methemoglobin, Fe3+)?

A) Potassium ferricyanide

B) Potassium cyanide

C) Sodium bicarbonate

D) Distilled water

E) Methylene blue

B

In the laboratory evaluation of microcytic hypochromic anemias, which parameter is considered the single best test to

detect early iron depletion?

A) Total Iron Binding Capacity (TIBC)

B) Serum Ferritin

C) Serum Iron

D) Transferrin Saturation

E) Hemoglobin Electrophoresis

B

What characteristic red blood cell inclusion is observed in Lead Intoxication due to the inhibition of enzymes in the

heme synthesis pathway?

A) Howell-Jolly bodies

B) Basophilic stippling

C) Cabot rings

D) Heinz bodies

E) Pappenheimer bodies

B

Anemia of Chronic Disease (ACD) is driven by elevated levels of which liver acute-phase hormone that blocks iron

release from macrophages?

A) Erythropoietin

B) Hepcidin

C) Ferritin

D) Transferrin

E) Interleukin-1

B

Which amino acid substitution defines Sickle Cell Hemoglobin (Hb S) at the molecular level?

A) Substitution of glutamic acid by lysine at position 6 of the beta chain

B) Substitution of glutamic acid by valine at position 6 of the beta chain

C) Substitution of glutamic acid by glutamine at position 121 of the beta chain

D) Deletion of four alpha-globin genes on chromosome 16

E) Mutation in the band 3 membrane protein

B

Which solubility screening test uses saponin and sodium dithionite to detect the presence of Hemoglobin S based on

tactoid formation?

A) Isopropanol precipitation test

B) Dithionite solubility test

C) Acidified serum test (Ham's test)

D) Sucrose hemolysis test

E) Ascorbate cyanide test

B

Which metabolic enzyme deficiency in the hexose monophosphate shunt leads to Heinz body formation and episodic

hemolysis during oxidative stress?

A) Pyruvate kinase (PK)

B) Glucose-6-phosphate dehydrogenase (G6PD)

C) Methemoglobin reductase

D) Delta-ALA synthetase

E) Uroporphyrinogen III cosynthetase

b

In automated cell counters, what is the spurious effect of a markedly elevated White Blood Cell count (>50,000/µL) on

CBC parameters?

A) Spurious decrease in hemoglobin and increase in hematocrit

B) Spurious increase in both hemoglobin and hematocrit

C) Spurious decrease in both hemoglobin and hematocrit

D) No effect on automated parameters

E) Spurious decrease in MCH and MCHC

b

Reticulocytes contain residual RNA that precipitates into visible blue granulofilamentous material when stained with

which supravital dye?

A) Wright-Giemsa stain

B) New Methylene Blue

C) Prussian Blue

D) Crystal Violet

E) Eosin Y

b

What is the gold standard diagnostic test for confirming Paroxysmal Nocturnal Hemoglobinuria (PNH) by detecting

missing GPI-anchored proteins (CD55/CD59)?

A) Sucrose hemolysis test

B) Flow cytometry (or FLAER test)

C) Ham's acidified serum test

D) Direct Antiglobulin Test (DAT)

E) Osmotic fragility test

b

Which peripheral blood feature characteristically distinguishes Megaloblastic Anemia from Non-megaloblastic

macrocytic anemia?

A) Presence of target cells and spherocytes

B) Macro-ovalocytes and hypersegmented neutrophils

C) Large round macrocytes with normal leukocytes

D) Schistocytes and helmet cells

E) Microcytic hypochromic RBCs with stippling

c

Which condition is caused by a structural defect in erythrocyte membrane vertical interactions, leading to loss of

membrane surface area and spherocyte formation?

A) Hereditary Elliptocytosis

B) Paroxysmal Nocturnal Hemoglobinuria

C) Hereditary Spherocytosis

D) Southeast Asian Ovalocytosis

E) Abetalipoproteinemia

c

Which metabolite elevation specifically differentiates Vitamin B12 deficiency from Folate deficiency?

A) Elevated Homocysteine with normal Methylmalonic Acid

B) Decreased serum ferritin and high TIBC

C) Elevated levels of BOTH Methylmalonic Acid (MMA) and Homocysteine

D) Decreased osmotic fragility

E) Positive Direct Antiglobulin Test

C

What specific poikilocyte is characteristic of Microangiopathic Hemolytic Anemia (MAHA) due to mechanical shearing

of red cells by microthrombi?

A) Codocytes (target cells)

B) Drepanocytes (sickle cells)

C) Schistocytes (helmet cells / fragmented RBCs)

D) Dacrocytes (teardrop cells)

E) Acanthocytes (spur cells)

C

Congenital Erythropoietic Porphyria (Gunther's Disease) is caused by a deficiency in which enzyme, resulting in severe

photosensitivity and red urine?

A) Delta-ALA dehydratase

B) Ferrochelatase

C) Uroporphyrinogen III cosynthetase

D) Uroporphyrinogen decarboxylase

E) Porphobilinogen deaminase

C

Which diagnostic laboratory test exposes patient lymphocytes to DNA cross-linking agents like Diepoxybutane (DEB) or

Mitomycin C?

A) Ham's acidified serum test

B) Isopropanol precipitation test

C) Chromosomal breakage analysis for Fanconi Anemia

D) Schilling test

E) Sugar water test

C

In Hemoglobin C (Hb C) disease, what is the specific amino acid substitution at position 6 of the beta-globin chain?

A) Glutamic acid to Valine

B) Glutamic acid to Glutamine

C) Glutamic acid to Lysine

D) Beta 26 Glutamic acid to Lysine

E) Alpha 68 Asparagine to Lysine

C

What is the normal reference range for Mean Corpuscular Hemoglobin Concentration (MCHC) in adult red blood cells?

A) 22 to 34 pg

B) 80 to 100 fL

C) 32 to 36 g/dL (or %)

D) 11.6 to 14.6 %

E) 39 to 46 fL

C

In severe liver disease, abnormal lipoproteins cause cholesterol accumulation in the outer RBC membrane layer,

forming irregular, spiky cells called:

A) Echinocytes (burr cells)

B) Stomatocytes

C) Acanthocytes (spur cells)

D) Spherocytes

E) Ovalocytes

c

In Alpha Thalassemia, the deletion of three alpha-globin genes (--/-α) leads to excess beta chains forming tetramers

(β4). What is this condition?

A) Bart's Hydrops Fetalis

B) Alpha Thalassemia Trait

C) Hemoglobin H Disease

D) Beta Thalassemia Major

E) Hemoglobin Lepor

c

Paroxysmal Cold Hemoglobinuria (PCH) is caused by a biphasic cold autoantibody (Donath-Landsteiner antibody)

directed against which antigen?

A) I antigen

B) Rh antigen

C) P blood group antigen

D) Kell antigen

E) Duffy antigen

d

Which classic diagnostic assay measures the intestinal absorption of radiolabeled Vitamin B12 before and after

Intrinsic Factor administration?

A) Deoxyuridine suppression test

B) Direct Antiglobulin Test

C) Formiminoglutamic acid (FIGLU) test

D) Schilling test

E) Ascorbate cyanide test

D

What is the correct mathematical formula for calculating Mean Corpuscular Hemoglobin Concentration (MCHC)?

A) (HCT % × 10) / RBC count

B) (HGB g/dL × 10) / RBC count

C) (SD of MCV / Mean MCV) × 100

D) (HGB g/dL × 100) / HCT %

E) HCT % / (MCV × RBC count)

D

In flow cytometry and optical light scatter automated analyzers, scattered light results from three physical light

interactions:

A) Absorption, Transmission, Fluorescence

B) Impedance, Resistance, Conductivity

C) Polarization, Depolarization, Excitation

D) Diffraction, Refraction, Reflection

E) Centrifugation, Sedimentation, Agglutination

D

In Pyruvate Kinase (PK) deficiency, red cells undergo premature destruction because PK is essential in glycolysis for

producing:

A) NADPH

B) Glutathione

C) 2,3-BPG

D) ATP

E) Heme

D

Which inherited aplastic anemia presents with progressive bone marrow hypoplasia, pancytopenia, short stature, thumb

malformations, and skin hyperpigmentation?

A) Diamond-Blackfan Syndrome

B) Shwachman-Diamond Syndrome

C) Pure Red Cell Aplasia

D) Fanconi Anemia

E) Southeast Asian Ovalocytosis

d

Which disorder is caused by an absence of beta-lipoproteins, leading to fat malabsorption, neurological deficits, retinitis

pigmentosa, and rigid acanthocytes?

A) Lecithin-Cholesterol Acyltransferase Deficiency

B) Hereditary Spherocytosis

C) Paroxysmal Nocturnal Hemoglobinuria

D) Abetalipoproteinemia

E) Spur Cell Anemia

d

What is the nuclear composition of Howell-Jolly bodies found as red blood cell inclusions in post-splenectomy

patients?

A) Precipitated RNA

B) Iron granules

C) Denatured hemoglobin

D) DNA fragments

E) Mitotic spindle remnants

d

What is the primary underlying cause of hypoproliferative anemia in Chronic Kidney Disease?

A) Inadequate dietary iron intake

B) Autoimmune destruction of erythroblasts

C) Defective globin chain synthesis

D) Decreased production of Erythropoietin (EPO) by damaged renal tissue

E) Vitamin B12 deficiency

D

In Sideroblastic Anemia, excess iron accumulates in the mitochondria of erythroid precursors, forming a collar around

the nucleus. What are these cells called?

A) Megaloblasts

B) Dacrocytes

C) Spherocytes

D) Ringed sideroblasts

E) Schistocytes

D

Which anaerobic bacterium causes fulminant intravascular hemolysis by producing an alpha-toxin (phospholipase C)

that destroys RBC membranes?

A) Plasmodium falciparum

B) Babesia microti

C) Bartonella bacilliformis

D) Clostridium perfringens

E) Borrelia burgdorferi

E

What is the standard formula for calculating Red Cell Distribution Width (RDW-CV)?

A) (MCV / RBC count) × 100

B) (HGB / HCT) × 100

C) (Mean MCV / Standard Deviation of MCV) × 100

D) (MCH / MCHC) × 100

E) (Standard Deviation of MCV ÷ Mean MCV) × 100

E

What is the structural composition of Cabot Ring inclusions seen on peripheral blood smears in severe anemias?

A) Precipitated ribosomal RNA

B) Aggregates of ferritin / iron

C) Precipitated beta-globin chains

D) Unstable denatured hemoglobin

E) Remnants of the mitotic spindle

E

Which clinical entity is a recognized cause of Non-megaloblastic macrocytic anemia characterized by large round

RBCs?

A) Pernicious Anemia

B) Folate deficiency

C) Vitamin B12 deficiency

D) Transcobalamin deficiency

E) Alcoholism and Chronic Liver Disease

E

Which characteristic panel of iron parameters confirms the diagnosis of Iron Deficiency Anemia (IDA)?

A) Increased Serum Iron, Increased Ferritin, Decreased TIBC

B) Normal Serum Iron, Decreased Ferritin, Normal TIBC

C) Increased Serum Iron, Decreased Ferritin, Increased TIBC

D) Decreased Serum Iron, Increased Ferritin, Decreased TIBC

E) Decreased Serum Iron, Decreased Ferritin, Increased TIBC

E

Which abnormal hemoglobin tetramer is composed of four gamma chains (γ4) and causes Bart's Hydrops Fetalis?

A) Hemoglobin A

B) Hemoglobin A2

C) Hemoglobin F

D) Hemoglobin H

E) Hemoglobin Bart's

E

What is the primary pathophysiologic defect in Pure Red Cell Aplasia (PRCA)?

A) Multilineage hematopoietic stem cell failure

B) Impaired intestinal absorption of folate

C) Defective iron utilization in protoporphyrin synthesis

D) Increased splenic sequestration of mature RBCs

E) Selective suppression or failure of erythroid progenitor cells

E

Which form of porphyria is caused by a deficiency of Uroporphyrinogen Decarboxylase, resulting in photodermatitis and

reddish urine without neurological involvement?

A) Congenital Erythropoietic Porphyria

B) Erythropoietic Protoporphyria

C) Acute Intermittent Porphyria

D) Hereditary Coproporphyria

E) Porphyria Cutanea Tarda

E

Southeast Asian Ovalocytosis (SAO) is a red cell membrane disorder that confers natural protection against which

infectious disease?

A) Babesiosis

B) Clostridial sepsis

C) Bartonellosis

D) Parvovirus B19 infection

E) Malaria

E

Which diagnostic laboratory test uses 17% isopropanol at 37°C to detect Unstable Hemoglobins by inducing rapid

precipitation?

A) Sugar water test

B) Ham's acidified serum test

C) Ascorbate cyanide test

D) Dithionite solubility test

E) Isopropanol precipitation test

E

March Hemoglobinuria (Exercise-Induced Hemoglobinuria) is an extrinsic hemolytic condition resulting from:

A) Intrinsic RBC membrane spectrin defect

B) Red cell glycolytic enzyme deficiency

C) Biphasic cold autoantibody complement activation

D) Fibrin microthrombi in small capillaries

E) External mechanical trauma from repetitive physical impact