39 Erythropoietic Effects if Endocrine Disorders

Question 1

TRUE OR FALSE

Anemia is a well-recognized complication of thyroidectomy and is associated with hypo- and hyperthyroidism and subclinical thyroid dysfunction.

Answer 1

TRUE

Anemia is a well-recognized complication of thyroidectomy and is associated with hypo- and hyperthyroidism and subclinical thyroid dysfunction.

Question 2

A normocytic normochromic anemia may be seen in primary adrenal insufficiency (Addison disease), but the anemia may also be masked by the concomitant (increase or decrease) in plasma volume

Answer 2

Decrease

Question 3

TRα or TRβ

Both TRα and TRβ proteins are expressed in human CD34+ progenitors, but only _______ is detectable in late erythroblasts.

Answer 3

TRβ

Question 4

TRUE OR FALSE

The anemia in hypothyroidism has been described variably as normocytic, macrocytic, or microcytic.

Answer 4

TRUE

The anemia in hypothyroidism has been described variably as normocytic, macrocytic, or microcytic.

• Significant reduction in their red cell mass, anemia is not always evident from hemoglobin and hematocrit values, owing to a concomitant reduction of plasma volume
• Chronic autoimmune (Hashimoto disease) thyroiditis have an increased incidence of chronic autoimmune gastritis and celiac disease, with resultant in impaired cobalamin and iron absorption
• Iron deficiency impairs TH synthesis by reducing the activity of heme-dependent thyroid peroxidase and may also alter central nervous system control of thyroid metabolism.

Question 5

TRUE OR FALSE

Thyroid hormone administration increases red cell production in animals, humans with hyperthyroidism generally have erythrocytosis.

Answer 5

FALSE

Although thyroid hormone administration increases red cell production in animals, humans with hyperthyroidism generally do not have erythrocytosis.

Question 6

Hematologic changes in primary adrenal insufficiency (Addison disease)

Answer 6

• Normocytic normochromic anemia (can be masked by the concomitant reduction in plasma volume)
• Transient anemia after initiation of hormone replacement therapy, presumably secondary to an increased plasma volume

Question 7

Autoimmune gastric atrophy (pernicious anemia) can occur in patients with autoimmune adrenal insufficiency

Manifestations include mucocutaneous candidiasis and hypoparathyroidism

Answer 7

Type I polyglandular autoimmune syndrome

Question 8

TRUE OR FALSE

Glucocorticoids interact with erythropoietin in vitro to reduce erythroid colony proliferation.

Answer 8

FALSE

Glucocorticoids interact with erythropoietin in vitro to enhance erythroid colony proliferation.

Question 9

Adrenal conditions associated with erythrocytosis

Answer 9

• Cushing syndrome
• Primary aldosteronism
• Bartter syndrome
• Congenital adrenal hyperplasia
• Pheochromocytomas, paraganglioma - rare

Strong association between testosterone levels and hemoglobin and hematocrit was demonstrated

Question 10

The most common cause of congenital adrenal hyperplasia is

Answer 10

21-hydroxylase deficiency

Question 11

The patients’ with pheochromocytomas, paraganglioma were heterozygous for various gain-of-function mutations of the gene encoding _________________, and erythropoietin transcript was present not only in tumor tissue but also in the surrounding normal tissue.

Answer 11

HIF-2α (EPAS1)

Consequently, resection of the tumor does not resolve the erythrocytosis

Question 12

TRUE OR FALSE

Sexually mature males have higher hemoglobin levels than prepubertal males, older males, and females.

Answer 12

TRUE

Sexually mature males have higher hemoglobin levels than prepubertal males, older males, and females.

Question 13

Hormone responsible for the sex difference in hemoglobin

Answer 13

Testosterone

Testosterone levels directly correlated with hemoglobin levels

Orchiectomy results in a median decrease in hemoglobin concentration of 120 g/L.

Question 14

Effects of Testosterone

Answer 14

• Promotes the differentiation of CD34+ umbilical cord cells into erythroid progenitor cells
• Associated with an increase in erythropoietin levels and a decrease in hepcidin levels

Question 15

The most common cause of pituitary insufficiency

Answer 15

Pituitary tumors or consequences of their therapy

Question 16

Deficiencies of which hormones are considered the major contributors to anemia of hypopituitarism

Answer 16

Thyroid hormones, adrenal hormones, and androgens

Regardless of the cause, hypopituitarism results in a moderately severe normochromic normocytic anemia, with an average hemoglobin level of 100 g/L.

Question 17

TRUE OR FALSE

Red cell survival is decreased in hypopituitarism and the marrow is hypoplastic.

Answer 17

FALSE

Red cell survival is normal in hypopituitarism, but the marrow is hypoplastic.

Question 18

Drug which which stimulates prolactin secretion, improved hemoglobin levels or reduced transfusions in three of nine patients with Diamond-Blackfan anemia

Answer 18

Metoclopramide

However, macroprolactinomas have not been associated with erythrocytosis, but with anemia, likely the result of a concomitant decrease in testosterone levels.

Question 19

TRUE OR FALSE

The anemia of hyperparathyroidism is normochromic and normocytic and resolves or improves after parathyroidectomy.

Answer 19

TRUE

The anemia of hyperparathyroidism is normochromic and normocytic and resolves or improves after parathyroidectomy.

Question 20

TRUE OR FALSE

The presence of marrow fibrosis may positively correlate with improvement in anemia after parathyroidectomy

Answer 20

TRUE

The presence of marrow fibrosis may positively correlate with improvement in anemia after parathyroidectomy

There is no correlation with marrow fibrosis and the duration of hyperparathyroidism

Question 21

TRUE OR FALSE

Secondary hyperparathyroidism in CKD, may contribute to refractoriness to erythropoietin therapy.

Answer 21

TRUE

Secondary hyperparathyroidism in CKD, may contribute to refractoriness to erythropoietin therapy.

Parathyroidectomy or medical treatment of hyperparathyroidism may improve anemia and decrease requirements for exogenous erythropoietin therapy.