urinary system notes pt 1

Question 1

bladder contraction post mortem gives it what appearance

Answer 1

the impression of a thickened bladder wall

Question 2

kidney size
- normal?
- what can cause increased size?
- what can cause decreased size?

Answer 2

• similar to each other
• 3 vertebrae long
  <><>
  Increased:
• due to edema
• fat
• blood
• urine retention
• nephron swelling/hypertrophy
• neoplasia
  <><>
  Decreased:
• hypoplasia
• fibrosis
• other shrinking things?

Question 3

colour of kidneys in older cats

Answer 3

pale-yellow kidneys due to increased fat content

Question 4

pathogen for pulpy kidney

Answer 4

C. perfringens Type D epsilon toxin

Question 5

• kindey cortical : medullary ratio
• mass proportions

Answer 5

• On cut surface the cortical-medullary ratio is 1:2 to 1:3
• cortex accounts for ~ 80 % of renal mass

Question 6

what part of the kidney is larger in desert animals and why?

Answer 6

larger medullas as this part plays a role in urine concentration/water conservation

Question 6

why can horse urine often be cloudy, wheras most normal urine is clear?

Answer 6

• Horses have prominent mucous glands in their renal medullas and proximal ureters and often on cut surface significant mucus is present, often with fine crystals within the mucus.
• Related to this, the urine of horses can often be cloudy, whereas most normal urine is clear.

Question 7

Histologically, most of the lower urinary tract (ureters, bladder, as well as the renal pelvis) is lined by what type of cells?

Answer 7

• unique transitional non-keratinizing squamous epithelium known as the urothelium

Question 8

where does urinary tract epithelium change from urothelium to stratified squamous?

Answer 8

near or at the urethral opening

Question 9

is there lymph tissue in the bladder?

Answer 9

Lymphoid nodules are common findings in the urinary bladder lamina propria in all species; with inflammation or antigenic stimulation they can become large enough to be visible.

Question 10

what parts of the kidney should we submit for histopath?

Answer 10

• all sections of the kidney must be present, from cortex to papilla, with the section of similar width at the cortex and at the papilla.

Question 11

four main renal components (evaluated on histopath examination)

Answer 11

• Glomeruli
• Tubules
• Interstitial tissue
• Vasculature

Question 12

• what locations do we find glomeruli in?
• what makes up the renal corpuscule?

Answer 12

• cortical and juxtamedullary
• Bowman’s capsule together with the glomerulus and the uriniferous space make up the renal corpuscle

Question 13

the part of the kidney most susceptible to ischemia?
- what else are these stuctures sensitive to?

Answer 13

tubules
- also sensitive to toxins
> lesions in these components are often non-specific

Question 14

causes of expanded interstitial tissue in the kidney

Answer 14

• edema, cellular infiltrates, and/or fibrosis

Question 15

when can renal biopsy be useful?

Answer 15

• acute diseases:
  > acute renal failure
  > acute glomerulonephritis
  > nephrotic syndrome
  > asymptomatic proteinuria

Question 16

characteristics of chronic lesions in the kidney

Answer 16

• much as occurs in many other tissues, all lesions drift towards a similar end point with fibrosis and mononuclear inflammation as central features.
• In these situations, determining a cause for the disease is often not possible

Question 17

blockage of the ureters, bladder, and/or urethra can result in what conditions?

Answer 17

• hydronephrosis
• hydroureter
• bladder distension
• hydrourethra
• rupture

Question 18

two broad types of conditions that affect the ‘plumbing’ of the lower urinary tract

Answer 18

• obstructions
• infections

Question 19

common causes of lower urinary tract obstruction? which is most common in small animals?

Answer 19

• urolithiasis > most common by far in domestic animals
• anatomic anomalies (both congenital and acquired)
• inflammatory conditions
• neoplasia

Question 20

Development of uroliths is complex and influenced by many factors including what?
what must be present for urolith formation?

Answer 20

• **sufficient amounts of calculogenic material
• urinary ph
• reduced water intake/urine concentration**
• infection
• obstruction
• structural abnormalities
  <><><><>
  For urolith formation to occur, supersaturation of the components of the salts that form the uroliths must be presen

Question 21

where can uroliths form?

Answer 21

in any part of the urinary tract from the renal pelvis to the urethra

Question 22

common outcomes from complete urethral obstruction?

Answer 22

With complete urethral obstruction, urethral rupture is a more common outcome than hydronephrosis.

Question 23

high risk urolith locations in ruminants

Answer 23

• ischial arch, the sigmoid flexure, and the vermiform appendage of rams

Question 24

high risk urolith locations in dogs

Answer 24

• proximal end of the os penis

Question 25

where does urolith impaction occur in male cats

Answer 25

throughout the urethra

Question 26

what is ‘waterbelly’?

Answer 26

Production animals, particularly steers and wethers, are prone to develop urethral obstruction and a syndrome known as ‘waterbelly’, because of the copious amounts of fluid from a ruptured bladder

Question 27

uroliths are most important in what species?

Answer 27

• important in dogs, cats, cows, and sheep,
• less important in horses
• essentially not important in pigs

Question 28

most common stone type in cows and sheep?

Answer 28

silica