Pathology Of The Kidney Part 1

Front 1

What provides a "window" through which the clinician can view the functional & morphologic changes in the kidneys?

Back 1

Urine

Front 2

What is the functional unit of the kidney?

Back 2

Nephron

Front 3

True or false. The kidney is the second most common organ to get infarctions.

Back 3

False, Most prone organ to infarcts

Front 4

True or false. All species have a different number of nephrons per kidney, the bigger the animal the more nephrons/kidney.

Back 4

True

Front 5

What happens when the kidney loses a glomerulus?

Back 5

It's gone forever, but body has about 4Xs more than it needs so why you can be a kidney donor and still be fine

Front 6

What 3 cell types comprise the glomerulus?

Back 6

1) Endothelial cells
2) Epithelial cells
3) Mesangial cells

Front 7

What are the 2 types of epithelial cells in the glomerulus and where are they located?

Back 7

1) Visceral (podocytes) surround capillaries
2) Parietal: line bowman's capsule and are continuous with proximal convoluted tubules

Front 8

What are 3 functions of mesangial cells in the glomerulus?

Back 8

1) Phagocytic
2) Secretory
3) Contractile (regulation of blood flow)

Front 9

Where is the juxtaglomerular apparatus located?

Back 9

Between afferent and efferent arterioles

Front 10

What regulates blood flow to the glomerulus? How?

Back 10

Juxtaglomerular apparatus via tubuloglomerular feedback

Front 11

What cells produce renin? What is the sequel to renin production?

Back 11

Juxtaglomerular or granular cells produce renin in afferent arteriolar wall which leads to the production of angiotensin I, II from angiotensinogen produced by the liver and affects blood pressure.

Front 12

What 3 things comprise the glomerular filtration barrier?

Back 12

1) Fenestrae within endothelial cells of glomerular capillaries
2) Basement membrane
3) Epithelial slit pores of visceral epithelial cells

Front 13

What charge the layers of the glomerular filtration barrier? What happens if the charge is altered?

Back 13

Anionic charge on all layers
-If lose charge like w/ diabetes then lose substances into the urine

Front 14

What is the only continuous structure separating capillary blood from the urinary space?

Back 14

Basement membrane of glomerular filtration barrier

Front 15

Where and how is the glomerular filtrate produced?

Back 15

Formed in urinary spaces of renal glomerulus by filtration of plasma through the glomerular filtration barrier

Front 16

**The glomerular filtration barrier is permeable to what size of molecules?

Back 16

B/w 69,000 M.W. (albumin) and 68,000 M.W. (hemoglobin)
-So if see hemoglobin in urine glomerulus is still intact

Front 17

What does it mean if there's whole blood in the urine? How can you distinguish it from myoglobin?

Back 17

Means the bladder is bleeding bc RBCs are way to large to pass through glomerulus
-Can centrifuge & RBCs will centrifuge out
If doesn't spin out and not icteric=myoglobin

Front 18

The glomerular filtration barrier can be damaged by what 3 things?

Back 18

1) Inflammatory processes
2) Degenerative processes
3) Immunologic reactions

Front 19

Malfunction of the glomerular filtration barrier results in the _________ _______.

Back 19

Nephrotic syndrome

Front 20

The nephrotic syndrome is characterized clinically by what 5 things?

Back 20

1) Proteinuria
2) Hypoproteinemia= hypoalbuminemia
3) Anasarca (generalized edema)
4) Hypercholesterolemia
5) Lipiduria

Front 21

What part of the kidney synthesizes erythrogenin, the precursor of erythropoietin?

Back 21

Proximal convoluted tubule

Front 22

What part of the nephron has the highest cytochrome p450 (mixed function oxidase) activity?

Back 22

Proximal convoluted tubule

Front 23

What does the proximal convoluted tubule reabsorb?

Back 23

-Shunt glucose & Na+ by active transport
-Cl- accompanies Na+
-NaCl and glucose absorption carries 80% of the water in GF across nephron by osmotic diffusion
-Resorbs protein spillover from glomerulus

Front 24

What part of the kidney synthesizes Vitamin D3?

Back 24

Proximal convoluted tubule

Front 25

True or false. Glomerulus is a macroscopic structure.

Back 25

True

Front 26

What is the function of the Loop of Henle?

Back 26

Concentrate urine

Front 27

What are the 3 functions of the distal convoluted tubule?

Back 27

1) Resorption of H20 controlled by ADH from posterior pituitary
2) H+ secretion and urinary acidification=acid-base balance
3) K+ secretion

Front 28

What is diabetes insipidus?

Back 28

Deficiency of ADH

Front 29

What is nephrogenic diabetes insipidis? What are some causes?

Back 29

Failure of distal convoluted tubular cells to respond to ADH
-Pyometra, severe hepatic disease, hyperadrenocorticism, pyelonephritis, hypokalemia, hypoadrenocorticism, hyperthyroidism, acromegaly, renal disease, drugs, tumors

Front 30

What controls the rate of renin release?

Back 30

Macula densa

Front 31

What is the macula densa?

Back 31

Specialized distal tubular epithelial cells

Front 32

What is the function of macula densa?

Back 32

Provides feedback to afferent arteriole (tubuloglomerular feedback) regulating glomerular hemodynamics in response to NaCl concentration
-Also controls rate of renin release

Front 33

What are 3 congenital anomalies of the kidney?

Back 33

1) Aplasia, hypoplasia, dysplasia
2) Fusion of kidney ("horse shoe kidney)
3) Cystic and polycystic kidneys

Front 34

What animal most commonly gets hypoplastic kidneys?

Back 34

Cats

Front 35

What animals have a lobulated kidney?

Back 35

Cattle, polar bears, seals

Front 36

**_______ kidneys are normally freely movable within the abdominal cavity.

Back 36

Cat
-So can grab them and biopsy

Front 37

What is nephritis?

Back 37

Inflammation of the kidney

Front 38

What are 3 types of nephritis?

Back 38

1) Glomerulonephritis
2) Tubulointerstitial nephritis
3) Pyelitis (inflammation of renal pelvis)
-Pyelonephritis (renal pelvis & interstitium of kidney)

Front 39

What is glomerulonephritis?

Back 39

Interaction of immunologic & inflammatory reactants at a fixed tissue site (glomerulus) results in a loss of structural and functional integrity

Front 40

What are 2 causes of glomerulonephritis?

Back 40

1) Idiopathic=primary glomerulonephritis
2) Secondary glomerulonephritis
-Glomerular deposition of immune complexes

Front 41

What are 2 causes of secondary glomerulonephritis?

Back 41

-Antibodies react with antigens in glomerular basement membrane (antiglomerular basement membrane disease
-Immune complex disease

Front 42

What is immune complex disease?

Back 42

-Antibodies react with non-glomerular antigens in the circulation to form immune complexes which are deposited in the glomerulus
-Antibodies react w/ non-glomerular antigens that have been previously trapped in the glomerulus

Front 43

What is the pathophysiology of anti-glomerular basement membrane disease in humans and horses?

Back 43

-Patient makes Ab to autologous basement membrane
-Anti-GBM Ab binds to patients glomerular capillary BM
-Complement activated, chemotaxis occurs resulting in progressive damage to glomerular tufts via oxidants and proteases

Front 44

What is the pathophysiology of immune complex glomerulonephritis?

Back 44

-Soluble Ag-Ab complexes formed in Ag excess
-Localization of complexes along capillary BM in subendothelial, subepithelial or mesangial locations
-Binding of complement w/ subsequent chemotaxis
-Inflammation & damage to glomerulus by neutrophilic lysosomal enzymes, thromboxane, O2 derived free radicals and H2O2

Front 45

What are 5 ways the glomerulus responds to injury?

Back 45

1) Cellular proliferation
-Mesangial cells
-Endothelial cells
-Epithelial cells
2) Leukocytic infiltration
3) Thickening of basement membrane
4) Hyalinization=amorphous CT=basement membrane-like material
5) Necrosis

Front 46

What is the gross appearance of a kidney with glomerulonephritis?

Back 46

-Generally unmarkable
-General swelling & bulging
-Slight increase in firmness
-Finely granular or roughened surface
-Cortical pallor

Front 47

What are 5 morphologic types of glomerulonephritis?

Back 47

1) Proliferative glomerulonephritis
2) Membranous glomerulonephritis
3) Membranoproliferative (mesangiocapillary) glomerulonephritis
4) Sclerosing glomerulonephritis
5) Embolic glomerulonephritis (generally a sequel to localized infections elsewhere in the body)

Front 48

What is proliferative glomerulonephritis?

Back 48

Increase in cellularity of the glomerulus

Front 49

What is membranous glomerulonephritis?

Back 49

Abnormal thickening of glomerular basement membrane & mesangial matrix

Front 50

What can be seen on histo that is typical of membranous glomerulonephritis?

Back 50

"wire-loop" capillaries
Splitting and thickening of basal lamina

Front 51

What is membranoproliferative glomerulonephritis?

Back 51

Combination of the two types:
-Thickening of glomerular basement membrane and mesangial matrix (membranous) & increase in cellularity of glomerulus (proliferative)
-Includes epithelial crescents and tuftal adhesions

Front 52

What does it mean if there's sclerosing glomerulonephritis?

Back 52

Chronic change-end stage=obsolescent gloerulus

Front 53

Embolic glomerulonephritis is generally a sequel to what?

Back 53

Localized infections elsewhere in the body

Front 54

What are 2 localized infections that result in embolic glomerulonephritis?

Back 54

1) Vegetative endocarditis
2) Actinobacillosis=Shigellosis of foals

Front 55

What are the clinical signs of a foal born with shigellosis?

Back 55

Weak
Unable to stand
Hot painful joints
Die 18 hours to 1 month of age

Front 56

What are the lesions of a foal with embolic glomerulonephritis upon necropsy?

Back 56

Synovitis
Tiny, gray, evenly distributed renal cortical foci (abscesses)
-Bacterial emboli lodged in glomeruli

Front 57

What is high on your differentials if a foal's kidney has tiny, gray, evenly distributed renal cortical foci and arthritis?

Back 57

Actinobacillosis (shigellosis)
-ONLY IN FOALS/HORSES

Front 58

**What are the 2 major diseases responsible for heavy persistent proteinuria in dogs?

Back 58

1) Glomerulonephritis
2) Amyloidosis

Front 59

What type of glomerulonephritis does a pyometra cause in dogs?

Back 59

Reversible membranoproliferative glomerulonephritis possibly directed against bacterial or uterine antigens

Front 60

What type of glomerulonephritis does canine systemic lupus erythematosus (SLE) cause in dogs? What causes it?

Back 60

Membranous or membranoproliferative glomerulonephritis
-Caused by immune complexes of host DNA and anti DNA antibody and complement

Front 61

What kind of glomerulonephritis does heartworm disease cause?

Back 61

Membranous glomerulonephritis

Front 62

How does infectious canine hepatitis affect urine production?

Back 62

Release of glomerular and tubular antigens in urine

Front 63

True or false. Lyme disease can cause glomerulonephritis in dogs.

Back 63

True

Front 64

Glomerulonephritis in cats is generally associated with ___________.

Back 64

Feline leukemia virus

Front 65

What kind of glomerulonephritis usually develops in cats with FeLv?

Back 65

Generally membranous glomerulonephritis
-Appears to be quite common

Front 66

What 3 viruses can cause glomerulonephritis in cats?

Back 66

1) FeLV (most common)
2) FIP
-Associated w/ IC formation
3) FIV

Front 67

True or false. Glomerulonephritis is rare in horses.

Back 67

True

Front 68

What are 2 causes of glomerulonephritis in horses?

Back 68

1) Equine infectious anemia: streptococcus
-Generally membrano-proliferative
2) Ag/Ab complexes of antiglomerular basement membrane disease is common in horse, but clinical disease is rare

Front 69

What are 2 causes of glomerulonephritis in swine? What kind of glomerulonephritis does each cause?

Back 69

1) Hog cholera & african swine fever
-Proliferative or membranoproliferative
2) Porcine leukemia
-Membranoproliferative

Front 70

True or false. Glomerulonephritis is rarely present in ruminants.

Back 70

False, clinically important glomerular disease is rare, but up to 90% of sheep in the 7 mo-3 yr range have morphoogic or immunologic evidence of glomerulonephritis

Front 71

What causes mesangiocapillary (membranoproliferative) glomerulonephritis in Finnish-Landrace Lambs?

Back 71

Deficient in third component of complement so cannot solubilize immune complexes

Front 72

What are the 3 ways that diabetic (mellitus) glomerulonephropathy affects the kidneys?

Back 72

1) Sialyation (removes - charge)
2) Microangiopathy of afferent arteriole
3) Focal (tuftal) sclerosis=Kimmelstiel-wilson nodules

Front 73

True or false. Glomerular lipidosis is a common condition in dogs.

Back 73

False, Rare-only reported as a disease entity in dogs

Front 74

How does a kidney with renal amyloidosis appear?

Back 74

Lardaceous (waxy) appearance to kidney

Front 75

Where does amyloid accumulate in a dog with amyloidosis?

Back 75

Mesangial matrix
Basement membrane

Front 76

Where does amyloid accumulate in a cat and sometimes cattle and shar-pei dogs with renal amyloidosis?

Back 76

Medullary interstitium as well as glomeruli

Front 77

True or false. Renal amyloidosis is a hereditary disease in some animals including cheetahs.

Back 77

True

Front 78

What are the 2 types of amyloid related to amyloidosis?

Back 78

AA=reactive amyloidosis
AL=plasma cell dyscrasia (light chain fragments)

Front 79

Animals with amyloidosis can get thrombosis due to what 4 things?

Back 79

1) Decrease of antithrombin III
2) Increase fibrinogen
3) Dehydration
4) Uremic vascular damage

Front 80

What's one way to test a kidney for amyloid?

Back 80

Use iodine, but 25% of cases don't stain

Front 81

What are 2 other names for familial renal disease?

Back 81

Juvenile progressive renal disease=familial renal disease= renal dysplasia

Front 82

What animals are affected by familial renal disease?

Back 82

Generally occurs in dogs under 6 years of age.
-Also reported in horses

Front 83

What is the etiology of familial renal disease (Juvenile progressive renal disease, renal dysplasia)?

Back 83

Not known

Front 84

What is high on your differentials of a young animal with what looks like a kidney in chronic renal disease?

Back 84

Familial renal disease (juvenile progressive renal disease, renal dysplasia)

Front 85

In general, what are the effects of diseases of the renal tubules & interstitium?

Back 85

Tubular disease or tubulointerstitial disease demonstrates defects in concentrating ability or specific tubular defects of absorption or secretion

Front 86

What are 4 types of diseases of the renal tubules and interstitium?

Back 86

1) Acute tubulointerstitial nephritis
2) Chronic interstitial nephritis=end stage kidney=fibrosis
3) Pyelonephritis: inflammation of the renal pelvis and interstitium
4) Miscellaneous tubular disorders

Front 87

What are 4 types of acute tubulointerstitial nephritis?

Back 87

1) Toxic tubular nephrosis
2) Hypoxic nephrosis
3) Immunologic tubulointerstitial nephritis
4) Infectious interstitial nephritis

Front 88

____% of cardiac output goes to the kidneys.

Back 88

25%

Front 89

What part of the nephrons are most sensitive to toxic tubular nephrosis? Why?

Back 89

Proximal convoluted tubules bc highest in cytochrome p450

Front 90

Can the damage from toxic tubular nephrosis be reversed?

Back 90

Yes in about 10 days if not too extensive and basement membrane not destroyed

Front 91

What is a common clinical sign of animals with toxic tubular nephrosis?

Back 91

Often results in anuria

Front 92

What toxins cause toxic tubular nephrosis?

Back 92

Inorganic chemicals:
-Copper
-Heavy metals
Organic chemicals:
-CCl4, chlorinated hydrocarbons, sulfonamides, oxalates
-Ethylene glycol

Front 93

How does copper cause toxic tubular nephrosis?

Back 93

Direct tubular damage and hemoglobinemia nephrosis= lower nephron nephrosis

Front 94

How do heavy metals cause toxic tubular nephrosis?

Back 94

Excreted in glomeruli and concentrated in tubules where it causes massive necrosis

Front 95

True or false. Inclusion bodies can be seen with lead poisoning.

Back 95

True

Front 96

What are the pathologies associated with ethylene glycol?

Back 96

-Deposition of crystals in tubular lumens
-Crystalluria at 6 h
-Renal failure at 48 h
-Oxalate crystals found in a high % of normal calves

Front 97

What is the peracute toxicity related to ethylene glycol?

Back 97

Causes irritation to GI tract

Front 98

What is the acute toxicity related to ethylene glycol?

Back 98

Hypocalcemia and metabolic acidosis from glycolic acid

Front 99

How does a kidney appear when the animal has oxalate nephropathy from ethylene glycol?

Back 99

Just a pale kidney, may have brown mucous in pelvis
Can't tell from amyloidosis or glomerulonephritis

Front 100

What are some plant poisons that can cause toxic tubular nephrosis?

Back 100

Black oak and white oak toxic to cattle
Leaves and acorns poisonous
Rhubarb

Front 101

What are the clinical signs of toxic tubular nephrosis?

Back 101

Perirenal hemorrhage, edema, hemorrhagic enteritis, multifocal necrosis of proximal tubles

Front 102

What is the toxic principle of plant poisons that cause toxic tubular nephrosis?

Back 102

Pyrogallin
Gallic and tannic acid

Front 103

What are 2 antibiotics that cause toxic tubular nephrosis?

Back 103

1) amphotericin B
2) Gentamycin

Front 104

How does amphotericin B cause toxic tubular nephrosis?

Back 104

Combines with sterols in plasma membrane of fungal or tubular cells causing leakage of cytosol

Front 105

How does gentamycin cause toxic tubular nephrosis?

Back 105

Concentrates in renal cortex, inhibits protein synthesis, uncouple oxidative phosphorylation, inhibits lysosomal enzymes and Na-K-ATP

Front 106

How does endogenous toxemia cause toxic tubular nephrosis?

Back 106

Ketosis leads to lipidosis and tubular damage
e.g. pregnant cows taken off diet to prevent dystocia--> ketosis

Front 107

What part of the kidney is affected by hypoxic nephrosis?

Back 107

Limited to loops of henle and distal convoluted tubules=lower nephron nephrosis=crush syndrome

Front 108

What will you find on a UA of an animal with hypoxic nephrosis?

Back 108

Myoglobinemia
Hemoglobinemia

Front 109

What is the pathophysiology of hypoxic nephrosis?

Back 109

Unknown, but may be related to mechanical obstruction and renal ischemia

Front 110

What has to happen for hemoglobin to be excreted in the urine?

Back 110

Hemoglobin attaches to haptoglobin in the blood stream so must exhaust the haptoglobin supply before spillage into urine ocurs

Front 111

Why does obstruction easily lead to hypoxic nephrosis?

Back 111

Kidney has an inelastic capsule so obstruction increases back pressure mechanically occluding arteries leading to renal shutdown
shock decreases blood pressure

Front 112

How does myoglobin affect vasculature?

Back 112

Myoglobin stimulates endothelin-1 and plasminogen activating factor constricting afferent and efferent vasculature
-Contributes to hypoxic nephrosis

Front 113

What actually causes lipid peroxidation of tubules in an animal with hypoxic nephrosis?

Back 113

Ferrihemate resulting from myoglobin dissociation leads to lipid peroxidation of tubules

Front 114

What are 3 conditions that lead to myoglobinemia from hypoxic nephrosis?

Back 114

1) Monday morning disease: horses are stalled all weekend then worked hard and fed grapes (Acidic)
2) Capture myopathy: get to excited and rupture heart muscles
3) Crush syndrome

Front 115

What are 4 causes of hemoglobinemia from hypoxic nephrosis?

Back 115

1) Bovine bacillary hemoglobinuria
2) Incompatible blood transfusion
3) Copper poisoining in sheep
4) Red maple poisoning-horses

Front 116

What are 2 causes of immunologic tubulointerstitial nephritis?

Back 116

1) Immune complex tubular disease
2) Antitubular basement membrane autoantibody

Front 117

Antitubular basement membrane autoantibodies are sometimes associated with _______ that combine w/ tubular basement membrane as haptens.

Back 117

Antibiotics

Front 118

What are 4 causes of infectious interstitial nephritis?

Back 118

1) *Leptospirosis
2) Canine herpes virus infection
3) "white-spotted" kidneys-calves-E. coli?
4) FIP

Front 119

How does leptospirosis infect animals?

Back 119

Infection occurs through mucus membranes or abraded skin
-Host becomes bacteremic in 4-10 d

Front 120

What is the acute phase of canine leptosporosis?

Back 120

Organism arrives in renal interstitium hematogenously and migrates to tubule lumen

Front 121

What are 6 pathologies are associated with the acute phase of canine leptosporosis?

Back 121

1) Dehydration
2) Icterus (liver damage)
3) Petechiation
4) Liver cord cell dissociation
5) Damage to proximal convoluted tubules
6) Lymphadenopathy

Front 122

What are the 4 pathologies associated with the subacute phase of canine leptosporosis?

Back 122

1) Dehydration
2) Emaciation
3) Uremic odor
4) Inflammatory foci surround convoluted tubules at corticomedullary junction

Front 123

If you find a dead sea lion it is considered to be dead of what until proven otherwise?

Back 123

Leptosporosis

Front 124

How can you diagnose canine leptosporosis?

Back 124

Dark field microscopy of urine

Front 125

What pathology is associated with the acute phase of bovine leptosporosis?

Back 125

Hemolytic anemia

Front 126

What is seen on histopathology of bovine leptospirosis?

Back 126

Inflammatory foci in subacute phase scattered throughout cortex

Front 127

What pathologies are associated with porcine leptospirosis?

Back 127

Subclinical; associated with abortion and stillbirths

Front 128

What pathologies are associated with equine leptospirosis?

Back 128

Generally asymptomatic
Associated with abortions and periodic ophthalmia ("moon blindness")

Front 129

When can canine herpes virus infection be fatal?

Back 129

In neonatal puppies under 3 to 5 weeks of age

Front 130

What does canine herpes virus usually cause in adult dogs?

Back 130

Asymptomatic infection or causes tracheobronchitis

Front 131

What are the lesions associated with canine herpes virus infection in utero or during birth?

Back 131

1) Multisystem hemorrhage
2) Spleno-lymphomegaly
3) Focal necrosis w/ inclusions in multiple tissues including the glomerulus
4) "Turkey-egg" renal hemorrhage

Front 132

What are 2 causes of chronic interstitial nephritis?

Back 132

1) End stage kidney
2) Fibrosis

Front 133

What is pyelonephritis?

Back 133

Inflammation of the renal pelvis and interstitium

Front 134

What are 2 ways inflammation can spread to the renal pelvis and interstitium?

Back 134

1) Hematogenous descending infection
2) Ascending from renal pelvis via vesicoureteral reflux and intrarenal reflux

Front 135

Opportunity for infection to cause pyelonephritis is frequent actual infection is not, why?

Back 135

Because urine is bacteriostatic

Front 136

What are the 6 bacteriostatic properties of urine?

Back 136

1) Urine pH low
2) High concentration urea
3) Organic acids
4) IgA, IgM
5) Surface mucins
6) Flushing effect