Renal Flashcards
Which organism is the most commonly isolated pathogen from renal abcesses in foals?
A. Streptococcus spp.
B. Actinobacillus equili
C. Corynebacterium spp.
D. Staphylococcus spp.
B. Actinobacillus
Foals 2-4d of age greatest risk
Tx: penicillin/ampicillin + gentamycin/amikacin
Cattle -> Corynebact renale & E. coli
Recently calved cows / hard pull dystocia
Which electrolyte abnormalities would you most likely see initially in acute renal failure in a horse
A. Hypercalcemia, hyperphosphatemia, hyperkalemia, hyponatremia and hypochloremia
B. Hypocalcemia, hyponatremia, hypochloremia
C. Hypocalcemia, hyperphosphatemia, hyperkalemia, hyponatremia and hypochloremia
D. Hypocalcemia, hypophosphatemia, hyperkalemia, hyponatremia and hypochloremia
B. Hypocalcemia, hyponatremia, hypochloremia
In more severe cases with oliguria/anuria:
- hypercalcemia, hyperphosphatemia, hyponatremia
- metabolic acidosis
Which of the following serologic tests is recommended to test for acute Leptospirosis in cattle?
A. Microscopic agglutination test
B. PCR
C. Dark field microscopy
D. Culture
A. Microscopic agglutination test
-Detects ab
-Look for 4x rise between acute and convalescent samples, or going from negative to >100 titer (but sometimes won’t see with host adapted Hardjo infection)
-Cross-reactivity bt serovars
-Unsuitable for screening for carriers
A herd of sheep are moved to a pasture with partially wooded area. Several months later, some of the sheep begin to develop pigmenturia. When the urine is centrifuged, the supernatant is light yellow with a red pellet at the bottom of the sample tube. What is the most likely toxic principle at play?
A. Gallic acid
B. Soluble oxalates
C. Ptaquiloside
D. Prussic acid
C. Ptaquiloside
-Hematuria
-Chronic Braken Fern (Pteridium acquilinum) ingestion
Gallic - tannins / oaks / maple
Oxalates - pigweed / beets / curly dock / fireweed / rhubarb
Prussic acid - cyanide: cherry, johnson grass
Parasympathic innervation to the bladder is provided by which nerve?
A. Pudendal nerve
B. Pelvic nerve
C. Hypogastric nerve
D. Sciatic nerve
B. Pelvic nerve
-P”u”dendal nerve = “U” control it so it’s the somatic innervation, and external sfincter bladder
-“P”elvic nerve = “p” starts the name so it’s the parasympathetic innervation
-Hypogastric = only one left so it’s the sympathetic innervation
Penicillin and oxytetracycline have similar clearance values. Given what you know about these drugs would you expect their elimination half lives to be
A. the same
B. greater for Penicillin
C. greater for oxytetracycline.
Why?
C.
The clearance rate when the drugs are in the plasma are the same since they have the same clearance values, but oxytetracycline has a higher volume of distribution than penicillin so it has a longer T1/2.
Drug elimination = irreversible removal via all routes of elimination
Clearance = volume of fluid cleared of drug per unit time
Does the function of furosemide get affected by tubulointerstitial renal disease?
A. No, because the main method of clearance is via glomerular filtration.
B. Yes, because the main method of clearance is via tubular secretion
Which aminoglycoside has the greates nephrotoxicity?
A. Gentamycin
B. Amikacin
C. Neomycin
D. Streptomycin
C. Neomycin
Neomycin has the most cationic charges/molecule
-> aminoglycosides (cationic) bind phospholipids (anionic) on brush border of renal tubular epithelial cell membrane
Which of the following tetracyclines can lead to renal tubular necrosis and why?
A. Minocycline
B. doxycycline
C. Oxytetracycline
C. Oxytetracycline
-> is the only one that gets eliminated unchanged by the kidney.
Minocycline and doxycycline get eliminated in the bile
Where is the most common site of urethral obstruction in male horses? why?
In the ischial arch, because it is the narrowest point in the male’s urethra. In females obstruction does not occur as often because their urethra is shorter, nontortuous and more distensible.
Which are the 3 major or most common causes of polyuria and polydipsia in
horses?
renal failure, PPID, psychogenic polydipsia (most common).
The less common causes of PU/PD are excessive salt consumption, diabetes mellitus
and insipidus, SIRS, and also iatrogenic (diuretics, corticosteroids, a2 agonists.)
Which are the 3 mechanisms of PPID to develop PU and PD?
glucosuria (osmotic diuresis), Antagonism of the action of antidiuretic hormone (ADH)
on the collecting ducts by excess cortisol and decrease ADH production and release
(adenoma) Growth of the adenoma (as PPID becomes more advanced) may lead to
impingement on the posterior pituitary and hypothalamic nuclei (the sites of ADH storage
and production).
What is the difference between nephrogenic diabetes insipidus and neurogenic?
Neurogenic (central) inadequate secretion of ADH. (acquired)
- Nephrogenic, decreased sensitivity of the renal epithelial cells of the collecting
ducts to circulating ADH or loss of ADH receptors on these cells.
With both forms of DI, dramatic PU/PD may be reported and affected animals fail to concentrate
urine in the face of water deprivation.
How can you differentiate nephrogenic diabetes from neurogenic for diagnosis?
Both affected animals fail to concentrate urine in the face of dehydration. neurogenic
DI can be differentiated from nephrogenic DI by measuring plasma ADH (AVP)
concentration or by administration of synthetic ADH (DDAVP or desmopressin)
- After administration of exogenous ADH, if USG rises in response, then this indicates
neurogenic DI, whereas a lack of urine concentration indicates nephrogenic DI.
What are the normal chemistry findings that characterizes renal tubular acidosis?
hypochloremic metabolic acidosis with normal anion gap. This is a characteristic
found in both types of RTA.
Normally,H+ is excreted when bicarbonate is reabsorbed in the proximal tubules. Thus,
acidosis with both type I and type II RTA results from decreased H+ excretion.
- Hyperchloremia develops as a result of an increased renal absorption of chloride ions
subsequent to bicarbonate loss.
Describe the pathophysiology of renal tubular acidosis type 1.
Develops when distal tubular excretion of hydrogen ions (H+) is compromised,
and affected patients are unable to produce acidic urine.
- Type I RTA results in more severe acidosis and electrolyte abnormalities, since the
distal tubule is responsible for maximal acidification of the urine.
- In the absence of H+ excretion, potassium ions (K+) are excreted in exchange to
maintain electroneutrality, which can result in severe hypokalemia.
Describe the pathophysiology of renal tubular acidosis type 2.
Results from decreased proximal tubular bicarbonate resorption and subsequent
urinary loss of bicarbonate.
- Is often a self-limiting problem but may be accompanied by more widespread
proximal tubular dysfunction known as Fanconi syndrome, which is characterized
by defective resorption of glucose, amino acids, phosphate, potassium, sodium,
calcium, magnesium, uric acid, and other organic acids.
- Fanconi syndrome may be a primary (inherited) disorder or can develop
secondary to renal, metabolic, and autoimmune diseases or drug administration.
In septic foals, bladder necrosis leading to leakage of urine may occur, possibly
secondary to hematogenous spread of bacteria. Which is the most common
bacteria related to hematogenous spread in foals?
a) E. coli.
b) Fusobacterium necrophorum.
c) Salmonella spp.
a) E. coli.
- Ulcerative Posthitis and Vulvitis. (enzootic balanoposthitis, pizzle rot, sheath rot)
is an ulcerative bacterial infection of the mucous membrane and surrounding skin of the prepuce and vulva. What is the most common pathogen related to UPV?
a) Corynebacterium renale.
b) Fusobacterium necrophorum. (second most common).
c) Contagious ecthyma (orf).
d) Caprine and ovine herpesvirus.
a) Corynebacterium renale.
= urea producing bacteria
Prevention:
-> less protein in the diet since it is a substrate (nitrogen) to turn into urea
Which are the most common sites of urethral obstruction in ruminants (small
ruminants and cattle).
Distal aspect of the sigmoid flexure.
- Near the insertion of the retractor penis muscles in cattle.
- The urethral process in sheep and goats + sigmoid flexure
