Path 14 Flashcards

Approximately how long does erythroid maturation from proerythroblast to reticulocyte take?

A) 5–7 days

B) 1–2 days

C) 10–14 days

D) 20–25 days

What is the typical lifespan of a mature erythrocyte?

A) 30 days

B) 60 days

C) 120 days

D) 180 days

Where are most aging erythrocytes normally removed from circulation?

A) Liver

B) Spleen

C) Kidneys

D) Bone marrow

Which type of hemolysis is most associated with splenomegaly?

A) Extravascular hemolysis

B) Intravascular hemolysis

C) Mechanical hemolysis

D) Complement-mediated intravascular hemolysis

Which type of hemolysis is typically caused by mechanical destruction of erythrocytes?

A) Extravascular hemolysis

B) Intravascular hemolysis

C) Splenic sequestration

D) Ineffective erythropoiesis

Which type of hemolysis can produce jaundice?

A) Only extravascular hemolysis

B) Both intravascular and extravascular

C) Only intravascular hemolysis

D) Neither type of hemolysis

Which bilirubin fraction typically increases during hemolytic anemia?

A) Conjugated bilirubin

B) Direct bilirubin

C) Delta bilirubin

D) Unconjugated bilirubin

Which type of hemolysis is most associated with hemoglobinuria?

A) Extravascular hemolysis

B) Splenic sequestration

C) Ineffective erythropoiesis

D) Intravascular hemolysis

Which immature erythrocytes increase in response to hemolytic anemia?

A) Myeloblasts

B) Megakaryocytes

C) Lymphoblasts

D) Reticulocytes

Which gastrointestinal complication can result from chronic hemolytic anemia?

A) Pigment gallstones

B) Cholesterol polyps

C) Peptic ulcers

D) Pancreatic pseudocysts

What is the typical inheritance pattern of hereditary spherocytosis?

A) X-linked recessive

B) Autosomal dominant

C) Mitochondrial

D) Autosomal recessive

Which RBC membrane proteins are commonly defective in hereditary spherocytosis?

A) Globin and ferritin

B) Actin and myosin

C) Glycophorin and hemoglobin

D) Spectrin and ankyrin

Which additional membrane proteins may be defective in hereditary spherocytosis?

A) CD3 and CD20

B) Fibrinogen and albumin

C) Band 3 and protein 4.2

D) Collagen and elastin

Which procedure can significantly reduce hemolysis in hereditary spherocytosis?

A) Thymectomy

B) Splenectomy

C) Cholecystectomy

D) Lymphadenectomy

In hereditary spherocytosis, where specifically within the spleen do spherocytes get trapped?

A) Hepatic sinusoids

B) Renal glomeruli

C) Cords of Billroth

D) Pulmonary capillaries

Why does splenectomy improve anemia in hereditary spherocytosis?

A) Restores normal spectrin synthesis

B) Increases erythrocyte hemoglobin production

C) Corrects membrane protein mutations

D) Reduces splenic erythrocyte destruction

Deficiency of which enzyme causes susceptibility to oxidative hemolysis?

A) Pyruvate kinase

B) Glucose-6-phosphate dehydrogenase

C) Hexokinase

D) Lactate dehydrogenase

G6PD deficiency impairs production of which molecule needed for antioxidant protection?

A) ATP

B) NADH

C) NADPH

D) FADH2

What is the inheritance pattern of G6PD deficiency?

A) Autosomal dominant

B) X-linked

C) Mitochondrial

D) Autosomal recessive

G6PD deficiency provides partial protection against which pathogen?

A) Plasmodium falciparum

B) Trypanosoma cruzi

C) Leishmania donovani

D) Toxoplasma gondii

Which RBC inclusions are characteristic of G6PD deficiency?

A) Howell-Jolly bodies

B) Pappenheimer bodies

C) Heinz bodies

D) Döhle bodies

What do Heinz bodies represent in erythrocytes?

A) Residual nuclear DNA

B) Aggregated ribosomal RNA

C) Denatured hemoglobin

D) Iron-containing mitochondria

Which peripheral blood cell morphology is characteristic of G6PD deficiency?

A) Target cells

B) Teardrop cells

C) Sickle cells

D) Bite cells

How are bite cells formed in G6PD deficiency?

A) Hemoglobin polymerization inside RBCs

B) Mechanical destruction by heart valves

C) Loss of membrane cytoskeleton

D) Splenic removal of Heinz bodies

Which pattern of hemolysis can occur in G6PD deficiency?

A) Both intravascular and extravascular

B) Only intravascular

C) Only extravascular

D) Neither type of hemolysis

Which factor commonly triggers hemolysis in G6PD deficiency?

A) Oxidative stress

B) Increased oxygen delivery

C) Elevated erythropoietin

D) Increased dietary calcium

Why is marked splenomegaly usually absent in common episodic G6PD deficiency?

A) RBC production completely stops

B) Splenic macrophages become inactive

C) Hemolysis occurs exclusively intravascularly

D) Hemolysis is intermittent rather than chronic

How do most individuals with sickle cell trait present?

A) Usually asymptomatic

B) Severe chronic anemia

C) Persistent hemoglobinuria

D) Massive splenomegaly

Sickle cell trait is particularly prevalent in individuals with ancestry from which region?

A) Northern Europe

B) East Asia

C) Sub-Saharan Africa

D) Arctic regions

Which hemoglobin reduces sickling severity by inhibiting HbS polymerization?

A) HbA2

B) HbC

C) HbA

D) HbF

Why does increased HbF reduce the severity of sickle cell disease?

A) Increases erythrocyte membrane cholesterol

B) Stimulates splenic erythrocyte production

C) Reduces HbS polymerization

D) Increases hemoglobin oxidation

Why can MCHC increase in sickled erythrocytes?

A) Increased hemoglobin synthesis

B) Increased fetal hemoglobin production

C) Loss of intracellular water

D) Increased erythrocyte iron uptake

How can coexisting alpha-thalassemia sometimes reduce erythrocyte sickling in HbSS disease?

A) Reduces intracellular hemoglobin concentration

B) Increases erythrocyte oxygen consumption

C) Increases HbS polymer formation

D) Eliminates abnormal beta-globin production

Which type of hemolysis commonly occurs in sickle cell disease?

A) Exclusively intravascular

B) Predominantly extravascular, with intravascular hemolysis

C) Exclusively extravascular

D) Neither intravascular nor extravascular

Which RBC inclusion is associated with functional asplenia in sickle cell disease?

A) Heinz bodies

B) Basophilic stippling

C) Pappenheimer bodies

D) Howell-Jolly bodies

Which skull radiographic appearance can occur in severe sickle cell disease and thalassemia?

A) Salt-and-pepper appearance

B) Hair-on-end appearance

C) Ground-glass appearance

D) Sunburst appearance

Which organ undergoes repeated infarctions leading to functional asplenia in sickle cell disease?

A) Spleen

B) Liver

C) Kidney

D) Pancreas

Which virus commonly precipitates aplastic crisis in sickle cell disease?

A) Epstein-Barr virus

B) Cytomegalovirus

C) Parvovirus B19

D) Hepatitis B virus

Which medication increases fetal hemoglobin production in sickle cell disease?

A) Methotrexate

B) Hydroxyurea

C) Erythropoietin

D) Deferoxamine

How does hydroxyurea reduce sickling in sickle cell disease?

A) Increases HbA2 production

B) Accelerates erythrocyte destruction

C) Decreases alpha-globin synthesis

D) Increases HbF and reduces polymerization

Which chromosome contains the alpha-globin genes?

A) Chromosome 16

B) Chromosome 11

C) Chromosome 7

D) Chromosome 21

How many alpha-globin genes are normally present in a diploid human cell?

A) One

B) Two

C) Four

D) Six

Which chromosome contains the beta-globin gene?

A) Chromosome 16

B) Chromosome 11

C) Chromosome 22

D) Chromosome 9

How many beta-globin genes are normally present in a diploid human cell?

A) Four

B) Six

C) One

D) Two

Thalassemia is historically associated with which geographic region?

A) Mediterranean basin

B) Northern Europe

C) Arctic regions

D) Central America

Which mutation commonly produces reduced beta-globin synthesis in beta-plus thalassemia?

A) Complete gene deletion

B) Chromosomal translocation

C) Splice-site mutation

D) Trinucleotide repeat expansion

Which mutation can cause absent beta-globin production in beta-zero thalassemia?

A) Promoter duplication

B) Nonsense mutation

C) Silent mutation

D) Intron polymorphism

What is premature destruction of erythroid precursors within the bone marrow called?

A) Extravascular hemolysis

B) Reticulocytosis

C) Erythrocytosis

D) Ineffective erythropoiesis

Which type of hemolysis predominates in beta-thalassemia?

A) Extravascular hemolysis

B) Intravascular hemolysis

C) Mechanical hemolysis

D) Complement-mediated intravascular hemolysis

Which anemia is characteristic of beta-thalassemia?

A) Normocytic, normochromic

B) Macrocytic, hyperchromic

C) Microcytic, hypochromic

D) Normocytic, hyperchromic

Which hepcidin pattern commonly occurs in severe beta-thalassemia with ineffective erythropoiesis?

A) Increased hepcidin, decreased erythroferrone

B) Decreased hepcidin, increased erythroferrone

C) Increased hepcidin, increased erythroferrone

D) Decreased hepcidin, decreased erythroferrone

What can result from hepcidin suppression in beta-thalassemia?

A) Reduced intestinal iron absorption

B) Decreased hepatic iron accumulation

C) Increased renal iron excretion

D) Excessive intestinal iron absorption

What is the term for erythrocytes that vary in size?

A) Anisocytosis

B) Poikilocytosis

C) Polychromasia

D) Hypochromia

What is the term for erythrocytes that vary in shape?

A) Anisocytosis

B) Reticulocytosis

C) Poikilocytosis

D) Macrocytosis

Which peripheral blood finding is characteristic of beta-thalassemia?

A) Spherocytes

B) Target cells

C) Bite cells

D) Schistocytes

What causes the hair-on-end skull appearance in severe thalassemia?

A) Increased bone mineralization

B) Premature cranial suture fusion

C) Decreased osteoblast activity

D) Marrow expansion from erythroid hyperplasia

Which hemoglobin fraction is typically elevated in beta-thalassemia minor?

A) HbA2

B) HbS

C) HbC

D) HbH

What is the most common genetic mechanism of alpha-thalassemia?

A) Splice-site mutations

B) Trinucleotide repeat expansions

C) Alpha-globin gene deletions

D) Chromosomal inversions

Deletion of one alpha-globin gene typically produces which condition?

A) HbH disease

B) Silent carrier state

C) Hydrops fetalis

D) Severe thalassemia major

How many alpha-globin gene deletions typically cause HbH disease?

A) One

B) Two

C) Four

D) Three

Which abnormal hemoglobin tetramer forms in HbH disease?

A) Four beta chains

B) Four alpha chains

C) Four gamma chains

D) Two alpha and two delta chains

Why does HbH impair oxygen delivery to tissues?

A) Reduced oxygen binding capacity

B) Increased hemoglobin degradation

C) Excessively high oxygen affinity

D) Complete absence of heme

Deletion of how many alpha-globin genes typically causes Hb Bart's hydrops fetalis?

A) Two

B) Four

C) One

D) Three

Which abnormal hemoglobin tetramer characterizes Hb Bart's hydrops fetalis?

A) Four beta chains

B) Four alpha chains

C) Four delta chains

D) Four gamma chains

Which gene is characteristically mutated in paroxysmal nocturnal hemoglobinuria?

A) PIGA

B) JAK2

C) HBB

D) BCL2

What type of hemolysis is characteristic of paroxysmal nocturnal hemoglobinuria (PNH)?

A) Intravascular hemolysis

B) Extravascular hemolysis

C) Ineffective erythropoiesis

D) Splenic sequestration

Which complement-regulatory proteins are deficient in PNH?

A) CD19 and CD20

B) CD3 and CD4

C) CD15 and CD30

D) CD55 and CD59

Which complement-regulatory protein normally accelerates the breakdown of C3 convertase?

A) CD20

B) CD34

C) CD59

D) CD55

Which complement-regulatory protein prevents membrane attack complex formation? '

A) CD59

B) CD55

C) CD19

D) CD15

Which serious vascular complication is strongly associated with PNH?

A) Arterial aneurysms

B) Thrombosis

C) Vasculitis

D) Capillary rupture

Which diagnostic test detects antibodies or complement bound to erythrocytes in autoimmune hemolytic anemia?

A) Osmotic fragility test

B) Direct Coombs test

C) Hemoglobin electrophoresis

D) Bleeding time

Which immunoglobulin is primarily responsible for warm autoimmune hemolytic anemia?

A) IgG

B) IgM

C) IgA

D) IgE

How are erythrocytes primarily destroyed in warm autoimmune hemolytic anemia?

A) Mechanical fragmentation

B) Direct bacterial destruction

C) Osmotic swelling

D) Splenic macrophage phagocytosis

Which antihypertensive medication can cause warm autoimmune hemolytic anemia?

A) Lisinopril

B) Methyldopa

C) Amlodipine

D) Hydrochlorothiazide

Which immunoglobulin is primarily associated with cold agglutinin hemolytic anemia?

A) IgG

B) IgA

C) IgM

D) IgE

Which respiratory pathogen is classically associated with cold agglutinin hemolytic anemia?

A) Streptococcus pneumoniae

B) Haemophilus influenzae

C) Legionella pneumophila

D) Mycoplasma pneumoniae

Which virus is classically associated with cold agglutinin hemolytic anemia?

A) Hepatitis A virus

B) Rotavirus

C) Epstein-Barr virus

D) Human papillomavirus

Which peripheral blood finding is characteristic of microangiopathic hemolytic anemia?

A) Schistocytes

B) Spherocytes

C) Target cells

D) Sickle cells

Which mechanical device can cause erythrocyte fragmentation and intravascular hemolysis?

A) Cardiac pacemaker

B) Insulin pump

C) Cochlear implant

D) Prosthetic heart valve

Which peripheral blood findings characterize megaloblastic anemia?

A) Spherocytes and reticulocytosis

B) Schistocytes and thrombocytosis

C) Macrocytes and hypersegmented neutrophils

D) Microcytes and target cells

Pernicious anemia results from impaired absorption of which vitamin?

A) Vitamin B12

B) Vitamin B6

C) Vitamin B9

D) Vitamin B1

Where is vitamin B12 primarily absorbed?

A) Duodenum

B) Jejunum

C) Terminal ileum

D) Colon

Which metabolites are elevated in vitamin B12 deficiency?

A) Lactate and pyruvate

B) Bilirubin and urobilinogen

C) Methylmalonic acid and homocysteine

D) Creatinine and uric acid

Which spinal cord tracts are affected by subacute combined degeneration in vitamin B12 deficiency?

A) Spinothalamic tracts and lateral corticospinal tracts

B) Anterior corticospinal tracts and spinothalamic tracts

C) Spinocerebellar tracts and lateral corticospinal tracts

D) Dorsal columns and lateral corticospinal tracts

Which oral finding can occur in vitamin B12 deficiency?

A) Gingival hyperplasia

B) Oral leukoplakia

C) Beefy red glossitis

D) Aphthous ulcers exclusively

Folate is required for the synthesis of which DNA nucleotide?

A) dTMP

B) dAMP

C) dGMP

D) dCMP

Which population has an increased risk of folate deficiency due to poor nutrition and impaired metabolism?

A) Patients with chronic alcohol use

B) Patients with isolated hypertension

C) Patients with seasonal allergies

D) Patients with mild asthma

Which metabolite is elevated in folate deficiency but not methylmalonic acid?

A) Pyruvate

B) Homocysteine

C) Lactate

D) Uric acid

Which complication distinguishes vitamin B12 deficiency from uncomplicated folate deficiency?

A) Macrocytic anemia

B) Neurological demyelination

C) Hypersegmented neutrophils

D) Elevated homocysteine

What is the most common nutritional deficiency worldwide?

A) Vitamin B12 deficiency

B) Folate deficiency

C) Vitamin C deficiency

D) Iron deficiency

In which oxidation state is nonheme iron transported into intestinal enterocytes by DMT1?

A) Fe2+

B) Fe3+

C) Fe4+

D) Fe0

What must happen to dietary ferric iron before absorption through DMT1?

A) Reduction to ferrous iron

B) Oxidation to ferric iron

C) Binding to hepcidin

D) Conversion into heme

Which transporter carries ferrous iron into intestinal enterocytes?

A) Ferroportin

B) DMT1

C) Transferrin

D) Ceruloplasmin

Where does most dietary iron absorption occur?

A) Terminal ileum

B) Proximal colon

C) Duodenum

D) Distal jejunum

Which enzyme primarily oxidizes exported Fe2+ into Fe3+ at the enterocyte membrane?

A) Ferrireductase

B) Hepcidin

C) DMT1

D) Hephaestin

Which transporter exports iron from enterocytes into circulation?

A) DMT1

B) Ferroportin

C) Transferrin

D) Ferritin

Which protein reduces intestinal iron absorption by promoting ferroportin degradation?

A) Erythropoietin

B) Transferrin

C) Hepcidin

D) Erythroferrone

A 45-year-old man develops unexplained iron deficiency anemia. Which underlying process should be investigated?

A) Increased erythropoietin production

B) Excessive platelet destruction

C) Acute lymphocyte proliferation

D) Chronic gastrointestinal blood loss

Which laboratory pattern is characteristic of iron deficiency anemia?

A) Decreased ferritin and serum iron

B) Increased ferritin and serum iron

C) Increased ferritin, decreased serum iron

D) Decreased ferritin, increased serum iron

What happens to transferrin and total iron-binding capacity (TIBC) in iron deficiency anemia?

A) Both decrease

B) Both increase

C) Transferrin increases, TIBC decreases

D) Transferrin decreases, TIBC increases

What happens to hepcidin levels in uncomplicated iron deficiency anemia?

A) Markedly increase

B) Decrease

C) Remain permanently elevated

D) Become completely absent

Which cytokine promotes hepcidin production in anemia of chronic inflammation?

A) IL-2

B) IL-5

C) IL-6

D) IL-12

Which laboratory pattern is characteristic of anemia of chronic inflammation?

A) Increased ferritin, decreased serum iron

B) Decreased ferritin, increased serum iron

C) Decreased ferritin, decreased TIBC

D) Increased serum iron, increased TIBC

What happens to TIBC and hepcidin in anemia of chronic inflammation?

A) Both increase

B) Both decrease

C) TIBC increases, hepcidin decreases

D) TIBC decreases, hepcidin increases

Which bone marrow disorder commonly causes anemia, neutropenia, and thrombocytopenia due to marrow failure?

A) Polycythemia vera

B) Aplastic anemia

C) Essential thrombocythemia

D) Hereditary spherocytosis

Which treatment exposure can cause acquired aplastic anemia through bone marrow toxicity?

A) Antihistamine therapy

B) Antacid therapy

C) Cytotoxic chemotherapy

D) Insulin therapy

What happens to reticulocyte levels in aplastic anemia?

A) Increase significantly

B) Remain consistently elevated

C) Fluctuate with meals

D) Decrease

Which virus commonly causes transient pure red cell aplasia?

A) Epstein-Barr virus

B) Cytomegalovirus

C) Parvovirus B19

D) Hepatitis A virus

Which mediastinal neoplasm is associated with acquired pure red cell aplasia?

A) Thymoma

B) Thyroid adenoma

C) Bronchial carcinoid

D) Schwannoma

Which hormone deficiency contributes to anemia in chronic kidney disease?

A) Thrombopoietin

B) Erythropoietin

C) Hepcidin

D) Granulocyte colony-stimulating factor