[B] 1.29 Uricosis (Gout)

Question 1

Uricosis

Answer 1

“Problem of the uric acid metabolism”

Question 2

Uricosis is seen in which animals?

Answer 2

• Birds
• Reptiles
• Apes
• Humans

Question 3

Give the excretory metabolism of birds & reptiles

Answer 3

Question 4

Give the excretory metabolism of mammals

Answer 4

Question 5

Give the plasma uric acid level of birds

Answer 5

Btw: 0.12-0.36 mmol/L

Question 6

In birds, if the plasma uric acid level is too high…

Answer 6

• Plasma
• Lymph
• In the kidney
• Serous membrane
• Mucous membrane
• Interstitium of organs
• Subcutaneous tissues
• In the cavity of joints and tendon sheaths

Question 7

Give the effects of uric acid

Answer 7

• Irritation of the neighbouring tissues
• Necrosis in cells
• Inflammation
• Foreign material to the body
  
  • Demarcation → Foreign body-type granuloma formation = Tophus

Question 8

Demonstration of uric acid

Answer 8

• No water based fixation
• Use ethanol
• Schultz-Schmidt staining → Uric acid will be Green

Question 9

Endogenous causes of avian uricosis

Answer 9

• Kidney agenesia
• Obstruction of the ureter

Question 10

Exogenous causes of avian uricosis

Answer 10

• Technopathies: Lack of water (dehydration), getting cold
• Vit. A deficiency
• Nephrotoxic compounds
• Rotten food
• Viruses (Avia nephritis virus)
• Protozoa (goose kidney coccidiosis)

Question 11

Retention uricosis causes of avian uricosis

Answer 11

• Disturbance in secretion of uric acid due to renal insufficiency
  
  • Uric acid will stay in the body

Question 12

Gout in mammals

Answer 12

• Uric acid precipitation and deposition in the kidney medulla
• Uric acid metabolism of dalmations
• Primates (Incl. humans)

Question 13

Gout in mammals:

• Uric acid precipitation and deposition in the kidney medulla

Answer 13

• In newborn piglets: Uricase is not active → Infarction
• Metabolites secreted as uric acid by the kidneys & precipitate
• Later solved & washed out (if milk & water supply is appropriate)

Question 14

Gout in mammals:

• Uric acid metabolism of dalmations

Answer 14

• Uricase is in the liver, but uric acid uptake is poor by the hepatocytes (Genetic defecit, recessive)
• Excess amount is excreted from the serum by the kidneys
• Secretion works well, but in severe tubular damage, gout can occur