lecture 9: metabolic disorders

Question 1

metabolic disorder

Answer 1

a disorder pertaining to nutrition, often caused by poor dietary intake or nutrient absorption

Question 2

anemia

Answer 2

general term for various red blood cell conditions affecting oxygen exchange in body

Question 3

congenital anemia

Answer 3

i.e sickle cell, thalassemia. genetic condition affecting hemoglobin synthesis. homozygous often fatal, heterozygous often advantageous

Question 4

acquired anemia

Answer 4

reduced hemoglobin level or RBC counts due to poor nutrition, other pathological factors, or environment

Question 5

thalassemia

Answer 5

a group of anemic conditions characterized by deficient hemoglobin production

Question 6

thalassemia major

Answer 6

high mortality rate. especially in infants and children with extensive skeletal involvement

Question 7

thalassemia in subadults

Answer 7

• thickening of bones due to enlargement of marrow spaces
• abnormal ephiseal fusion
• involvement of facial bones
• decreased vertebral height

Question 8

sickle cell anemia

Answer 8

• abnormal hemoglobin S gene
• in homozygous form, any hypoxemic stress can cause crystallization of the abnormal hemoglobin and RBC distortion
• heterozygous form often protects against malaria

Question 9

how does sickle cell anemia affect the bones?

Answer 9

1) secondary response to expansion of hemopoietic marrow 2) areas of necrosis due to vascular disruption 3) secondary infection due to vascular disruption

Question 10

1) secondary response to expansion of hemopoietic marrow

Answer 10

thickening of cranial vault, frontal bone, long bones, phalanges and vertebrae

Question 11

2) areas of necrosis due to vascular disruption

Answer 11

• large and small areas of necrotic bone formation; multiple or spotty
• femoral head most commonly affected

Question 12

3) secondary infection due to vascular disruption

Answer 12

associated with areas of necrosis

Question 13

iron deficiency anemia

Answer 13

caused by iron deficiency in the body

Question 14

2 ways body becomes iron deficient

Answer 14

1) heavy loss (bleeding etc.) 2) poor intake/nutrition/absorption

Question 15

porotic hyperostosis/ cribra orbitalia

Answer 15

iron deficiency anemia causes areas of marrow expansion in cranium

• characterized by thickening of diploe
• evidence of “hair on end” orientation of trabeculae

Question 16

what do porotic hyperostosis and cribra orbitalia indicate?

Answer 16

• congenital anemia, iron deficiency

- several other conditions (infectious, metabolic, vascular and neoplastic)

Question 17

scurvy

Answer 17

deficiency in vitamin C intake

• high mortality when severe
• categorized by livers inability to synthesize ascorbic acid

Question 18

infantile scurvy

Answer 18

1) Direct effects of vitamin C deficiency
- decreased mechanical stability
- decrease in osteoblasts
- continuation of osteoclasts and chrondroclasts
2) secondary changes due to trauma
- fractures, dislocation, hemorrhage

Question 19

infantile scurvy on skull

Answer 19

-porous hypertrophic bone formation due to chronic bleeding

Question 20

IS on ribs

Answer 20

fracture of osteochondral junction and posterior migration of sternum and costal cartilage

Question 21

IS on long bones

Answer 21

metaphyseal fractures, epiphysial dislocation, cortical thinning

Question 22

IS on scapula

Answer 22

porosity

Question 23

Adult scurvy traits

Answer 23

• less chance for skeletal lesions as person ages
• ribs fracture at osteochondral junction
• inflammation of alveolar bone and tissue due to chronic gingival hemorrhage

Question 24

vitamin D deficiency

Answer 24

poorly mineralized bone is prone to deformity and fracture from mechanical stress

Question 25

Rickets

Answer 25

- chronic vitamin D deficiency in early childhood - usually not before 4 months of age but quickly affects growing bones - accumulation of unmineralized bone and osteoid

Question 26

what do Rickets bone lesions reflect?

Answer 26

1) direct affects of metabolic disturbances 2) secondarty deformities 3) growth reduction

Question 27

How does rickets affect the cranium?

Answer 27

1) Craniotabes: thinning and softening of cranial vault 2) Cranial Base: superior displacement 3) cranial vault and base: deposition of finely porous subperiosteal bone