Ch. 28: Alterations of Hematologic Function in Children Flashcards
Which of the following is TRUE regarding fetal and adult hemoglobin?
Fetal hemoglobin is composed of two α- and two γ-chains.
Adult hemoglobin is composed of two α- and one γ-chain.
Adult hemoglobin is HbF and HbA.
Three of the embryonic hemoglobins are Gower 1, 2, and 3.
Fetal hemoglobin is composed of two α- and two γ-chains.
The adult hemoglobins are HbA and HbA2, and they are composed of two α- and two β-chains. Fetal hemoglobin is HbF and is composed of two α- and two γ-chains. The embryonic hemoglobins are Gower 1, 2, 3.
Which of the following is TRUE regarding anemia in children?
The most common cause is sickle cell disease.
Anemia is the most common blood disorder in children.
There is only one cause of hemolytic anemia.
Children rarely present with iron deficiency anemia.
Anemia is the most common blood disorder in children
Anemia is the most common blood disorder in children, and the most common cause is iron deficiency. There are two large categories for hemolytic anemia, including increased destruction and disorders related to damaging extraerythrocytic factors.
Which of the following statements is TRUE regarding iron deficiency anemia?
Whites are more commonly affected.
Incidence is most common in those children older than 2 years.
It is common in children due to their extremely high need for iron for normal growth.
There is decreased risk in children of homeless women.
It is the most common in children due to their extremely high need for iron for normal growth
Iron deficiency anemia is common in children due to their extremely high need for iron for growth. Incidence is not related to race but is related to socioeconomic factors, including increased prevalence in the children of homeless women. It is most commonly found between the ages of 6 months and 2 years.
Which of the following is TRUE regarding iron deficiency?
Splenomegaly is present in 90% of those affected.
Hemoglobin of less than 5 g/dl may be accompanied by pallor.
Hemoglobin of 10 g/dl is generally accompanied by tachycardia.
Widening of sutures is an early sign of iron deficiency.
Hemoglobin of less than 5 g/dl may be accompanied by pallor.
Splenomegaly is evident in 10% to 15% of children with iron deficiency anemia. If the condition is long-standing, the sutures of the skull may widen. Mild to moderate iron deficiency (hemoglobin 6 to 10 g/dl) may show some cellular changes. Hemoglobin less than 5 g/dl will demonstrate pallor, tachycardia, and a systolic murmur.
Which of the following is a TRUE statement regarding maternal antibodies?
Placental detachment does not result in fetal erythrocytes crossing the placenta.
The first Rh-incompatible pregnancy usually presents with severe complications.
Anti-Rh antibodies are formed only in the response to transfusion.
ABO incompatibility can cause hemolytic disease without erythrocytes escaping maternal circulation.
ABO incompatibility can cause hemolytic disease without erythrocytes escaping maternal circulation.
ABO incompatibility can cause hemolytic disease of the newborn without erythrocytes escaping maternal circulation. Placental detachment results in a large number of fetal erythrocytes entering the mother’s bloodstream. The first Rh-incompatible pregnancy usually presents with no difficulties. Anti-Rh antibodies are formed in the response to the presence of incompatible (Rh-positive) erythrocytes in the blood of an Rh-negative mother.
Which of the following is the appropriate term for an alloimmune disease in which maternal blood and fetal blood are antigenically incompatible? Erythroblastosis fetalis Hydrops fetalis Icterus neonatorum Icterus gravis neonatorum
Erythroblastosis fetalis
Hydrops fetalis is the term for fetuses that do not survive anemia in utero. They are stillborn with gross edema of the entire body. Icterus neonatorum is neonatal jaundice. Cerebral damage causes death, and this is caused by icterus gravis neonatorum.
Which of the following is TRUE regarding the Coombs test?
Indirect Coombs confirms the diagnosis of antibody-mediated hemolytic disease.
Indirect Coombs measures antibodies to the mother’s circulation.
Direct Coombs indicates if the fetus is at risk for hemolytic disease.
Direct Coombs measures free antibodies.
Indirect Coombs measures antibodies to the mother’s circulation.
The indirect Coombs measures antibody in the mother’s circulation and indicates if the fetus is at risk for hemolytic disease. The direct Coombs test measures antibody already bound to the surfaces of fetal erythrocytes and is used primarily to confirm the diagnosis of antibody-mediated hemolytic disease.
Which of the following is TRUE regarding G6PD deficiency?
Most commonly found in females
Most common manifestation is polycythemia
Associated with icterus neonatorum
Associated with green bean ingestion
Associated with icterus neonatorum
G6PD is most commonly found in males. It is associated with icterus neonatorum in Asian and Mediterranean infants. It results in hemolysis. Fava beans and the ingestion of certain drugs can cause a reaction.
Which of the following is associated with hereditary spherocytosis?
Autosomal recessive trait
25% are new mutations
Results in Heinz bodies
Another name for this disease is kernicterus
25% are new mutations
Twenty-five percent of cases are due to new mutations. It is autosomal dominant. Heinz bodies are found in G6PD. Another name for this condition is congenital hemolytic anemia or congenital acholuric jaundice.
Which of the following terms describes a person with Hb(s) and another type of abnormal Hgb? Sickle cell anemia Sickle cell thalassemia Sickle cell trait Hereditary spherocytosis
Sickle cell thalassemia
Sickle cell anemia has two Hb(s) genes. Sickle cell trait has one Hb(s) and one normal Hg(A). Hereditary spherocytosis often represents a new mutation.
Which of the following is a TRUE statement regarding sickle cell disease?
Sickle cell trait is the homozygous form of the disease.
Sickle cell disease means a person has HbA genes.
It is most common in European descent.
It is an autosomal recessive disease.
It is an autosomal recessive disease.
Sickle cell disease is most common in central Africa, the Near East, the Mediterranean, and part of India. Sickle cell trait has one Hb(s) and one normal Hg(A). In sickle cell disease, a person has two Hb(s) genes, and this represents the homozygous form of this disease. It is an autosomal recessive disorder.
Which of the following is the most common trigger for sickling? Hypoxemia Decreased hydrogen ions Decreased plasma osmolality High temperature
Hypoxemia
Hypoxemia is the most common cause of sickling. Sickling is an occasional, intermittent phenomenon that can be triggered or sustained by hypoxemia, increased hydrogen ion concentration in the blood (decreased pH), increased plasma osmolality, decreased plasma volume, and low temperature.
Which of the following is the appropriate term for a transient cessation in red blood cell production resulting in acute anemia? Vaso-occlusive crisis Aplastic crisis Sequestration crisis Hyperhemolytic crisis
Aplastic crisis
Vaso-occlusive crisis may develop spontaneously or be precipitated by infection, cold temperatures, dehydration, or low pH. This is when the cells clump and occlude vessels. Sequestration crisis is when large amounts of the blood become pooled in the liver and spleen. Hyperhemolytic crisis is unusual and often occurs with G6PD.
Which of the following hemophilias is autosomal recessive and is found equally in males and females? Hemophilia A Hemophilia B Hemophilia C von Willebrand disease
Hemophilia C
Hemophilia A and B are X-linked recessive and are found in men. Von Willebrand disease is autosomal dominant.