Lecture 58 - Gen Path Pigments

Question 1

what are the 4 pathways of abnormal intracellular accumulations

Answer 1

1. defect in metabolism
2. defect in protein folding
3. lack of enzyme (lysosomal storage disease)
4. ingestion/inhalation of indigestible materials

Question 2

Describe the intracellular accumulation of:

lipids

Answer 2

• best seen in the liver
• common in protein malnutrition, diabetes, obesity, etc.

Question 3

what are the mechanisms of lipidosis/steatosis

Answer 3

1. negative energy balance
2. decreased oxidation of FFA
3. decreased apoprotein synthesis
4. ineffective lipoprotein synthesis
5. ineffective lipoprotein transport

Question 4

T/F: negative energy balance is the most common mechanism of lipidosis

Answer 4

TRUE

Question 5

describe the gross and microscopic appearance of hepatic lipidosis

Answer 5

gross: enlarged liver, diffuse pallor, rounded edges, greasy

microscopic: large, discrete clear vacuoles that displace the nucleus

Question 6

T/F: hepatic lipidosis occurs focally or regionally

Answer 6

TRUE

Question 7

Atherosclerosis

Answer 7

cholesterol accumulation in arteries resulting from hypothyroidism or diabetes

Question 8

what are the gross and microscopic appearance of atherosclerosis

Answer 8

gross: medium-sized arteries are firm and white

microscopic: foamy macrophages

Question 9

describe the intracellular accumulation of:

glycogen

Answer 9

irregular borders of clear vacuoles
acquired causes = diabetes, Cushing’s, glucocorticoid admin.

Question 10

what 5 pigment accumulations are seen

Answer 10

1. red
2. green
3. yellow
4. brown
5. black

Question 11

what causes red discoloration of tissue

Answer 11

• vasodilation, hemorrhage, hemoglobin imbibition

Question 12

hemoglobin imbibition

Answer 12

post-mortem change
tissues uptake hemoglobin

Question 13

what causes green discoloration of tissue

Answer 13

• old hemorrhage (biliverdin) or eosinophilic infiltrate

Question 14

why is it uncommon to see green discoloration in mammalian species after hemorrhage

Answer 14

hemoglobin breaks down into hemosiderin rather than biliverdin

Question 15

What causes brown discoloration of tissue

Answer 15

• hemosiderin, ceroid-lipofuscin, and melanin

Question 16

when do we see hemosiderin accumulation?

Answer 16

1. hemolytic anemias - filtering organs turn brown
2. local excess - bruise, heart disease

Question 17

L-sided heart disease will cause what organ to have hemosiderin build-up

Answer 17

Lungs

Question 18

R-sided heart disease will cause what organ to have hemosiderin build-up

Answer 18

Liver

Question 19

why are heart failure cells present in the lungs

Answer 19

increased pressure in pulmonary vessels from backed up blood causes erythrocytes to be consumed by alveolar macrophages

Question 20

Lipofuscin

Answer 20

• wear and tear
• oxidative damage and age indicator
• heart and liver cells

Question 21

Ceroid

Answer 21

• pathological pigment
• oxidative injury, nutritional panniculitis, lysosomal storage disorder

Question 22

lipofuscin is commonly seen in what organ

Answer 22

heart

Question 23

ceroid is commonly seen in what organ

Answer 23

intestines (“brown dog gut”)

Question 24

what causes yellow discoloration in tissues

Answer 24

Bilirubin and carotenoid build up

Question 25

write the steps of erythrocyte breakdown

Answer 25

1. heme 2. biliverdin 3. bilirubin 4. conjugation in liver 5. urobilinogen in GIT

Question 26

what causes icterus

Answer 26

hyperbilirubinemia

Question 27

what are the causes of hyperbilirubinemia

Answer 27

1. pre-hepatic (hemolysis) 2. hepatic (liver disease; unconjugated form) 3. post-hepatic (obstruction of bile flow; conjugated form)

Question 28

what is the only endogenous black-brown pigment

Answer 28

melanin

Question 29

what locations are melanin pathologic

Answer 29

melanocytic neoplasms hyperpigmentation in skin

Question 30

what causes black pigment in tissues

Answer 30

pesudomelanosis (hydrogen sulfide producing bacteria) anthracosis (carbon dust accumulation)

Question 31

amyloidosis

Answer 31

- protein-folding disorder resulting in insoluble amyloid - predominantly extracellular - local or systemic

Question 32

what forms of amyloid are there

Answer 32

1. AA (amyloid A) 2. AL (amyloid light chain) 3. IAPP (Islet associated polypeptide) 4. AB (amyloid beta)

Question 33

describe AA

Answer 33

- serum amyloid A (positive acute phase protein) - hereditary to share pei, Abyssinian, and Siamese

Question 34

describe AL

Answer 34

- derived from light chains of antibodies - B-cell neoplasms or blood disorders

Question 35

Describe IAPP

Answer 35

- associated with diabetes in humans

Question 36

describe AB

Answer 36

- found in neural plaques of Alzheimer's

Question 37

describe the gross anatomy of amyloid

Answer 37

enlarged, waxy, pale organs dark brown with iodine

Question 38

describe the histomorphology of amyloid

Answer 38

pink color present at space of disse in liver = pressure atrophy of hepatic cords lymphoid follicles in spleen glomeruli of kidneys = protein loss

Question 39

what are the two kinds of mineralization?

Answer 39

1. dystrophic calcification 2. metastatic calcification

Question 40

describe dystrophic calcification

Answer 40

within mitochondria or membrane-bound matrix vesicles gross: fine, white granules or clumps histology: basophilic, granular

Question 41

describe metastatic mineralization

Answer 41

systemic Ca:P imbalance where the product is elevated (intercostal pleura, kidney, stomach, lungs, etc.)

Question 42

what are the causes of metastatic mineralization

Answer 42

renal disease (↑ P) hypervitaminosis D bone turnover (↑ Ca) hyperparathyroidism PTH related protein (↑ Ca)

Question 43

T/F: a functional tumor produces a hormone

Answer 43

TRUE

Question 44

T/F: primary hyperparathyroidism is concurrent with renal disease

Answer 44

FALSE - secondary