Urology AI 1 Flashcards
What can cause acute kidney injury (AKI)?
Severe hypercalcemia related to ingestion of certain rat poisons or psoriasis creams, and ethylene glycol intoxication.
What are the potential causes of hypocalcemia?
Ethylene glycol intoxication.
What concurrent changes in liver damage and function parameters are highly suspicious for possible leptospirosis?
Increased ALT, AST, ALP, bilirubin.
In suspected leptospirosis, what additional parameters, if present, suggest the possibility of active infection?
Anemia and/or thrombocytopenia on a complete blood count.
What is the importance of obtaining urine in AKI cases?
To check the specific gravity and exclude pre-renal azotemia.
What might sediment examination of urine reveal in cases of AKI?
Clues to the cause of AKI, such as calcium oxalate monohydrate crystals associated with ethylene glycol ingestion or concurrent bacterial infection suggesting pyelonephritis.
What does the presence of casts in the urine indicate?
Tubular damage in the kidneys, particularly cellular casts which represent the sloughing of tubular epithelium into the urine.
What imaging techniques can provide helpful information in diagnosing AKI?
Radiographs and ultrasound of the kidney.
What can be observed in cats with lymphoma on ultrasound?
Enlargement of both kidneys with hypoechoic subcapsular infiltrates.
What is the medullary rim sign observed in cases of ethylene glycol ingestion?
A line of increased opacity between the cortex and medulla of the kidney.
How can the diagnosis of leptospirosis be made in dogs?
By detecting specific antibodies through the microagglutination test (MAT) or detecting the organism itself by PCR in the blood or urine.
What is the diagnostic criteria for leptospirosis using the microagglutination test?
An acute titre >1:800 (or 1:1600 in a vaccinated dog) in the acute sample, or a four-fold increase in titre from acute to convalescent samples.
How can the diagnosis of ethylene glycol toxicity be challenging?
Because the animal is rarely seen ingesting it.
What clinical neurological signs in the initial presentation may help in diagnosing ethylene glycol toxicity?
Stupor or obtundation.
What are the biochemical abnormalities associated with ethylene glycol toxicity?
Azotemia, hypocalcemia, hyperglycemia.
What would be observed in the urine of an ethylene glycol toxic patient?
Calcium oxalate monohydrate crystals.
What can a Woods lamp reveal in cases of ethylene glycol toxicity?
The urine may fluoresce.
What is metabolic acidosis and how is it associated with ethylene glycol toxicity?
Metabolic acidosis is an acidosis of metabolic origin associated with a large anion gap, which is seen in ethylene glycol toxicity.
How is the anion gap calculated and what is considered a normal value?
The anion gap is calculated using the equation [Na+] - ([HCO3-] + [Cl-]). A normal value would be.
What is the preferred method for diagnosing leptospirosis?
Detecting specific antibodies through the microagglutination test (MAT).
Why is antibiotic treatment less likely to affect serology compared to PCR in diagnosing leptospirosis?
Because the immune response to the organism continues, whereas PCR may be affected by antibiotic treatment.
What features can help in diagnosing ethylene glycol toxicity?
Clinical neurological signs, biochemistry abnormalities, presence of calcium oxalate crystals in urine, and metabolic acidosis.
What can ultrasound reveal in dogs suspected of having leptospirosis?
Dilation of the renal pelvis (pyelectasia) and mass lesions in the kidney.
What is the significance of a line of increased opacity between the cortex and medulla of the kidney?
It is observed in ethylene glycol ingestion but is an unreliable sign of hypercalcemia.
How long does it take for specific antibodies to be produced in leptospirosis?
7-10 days after infection.
What is the time frame for collecting acute and convalescent samples in diagnosing leptospirosis?
7 days apart.
What can cause an increase in leptospirosis titers, other than active infection?
Recent vaccination or cross-reactivity between vaccinal and non-vaccinal serovars.
What can PCR detect in leptospirosis?
The organism itself in the blood or urine, and even in subclinical carriers.
What might help in diagnosing ethylene glycol toxicity if the animal is rarely seen ingesting it?
Clinical neurological signs, biochemical abnormalities, presence of calcium oxalate crystals in urine, and metabolic acidosis.
What are the possible outcomes of acute kidney injury (AKI)?
Possible outcomes of AKI include complete recovery, fatal AKI, or development of chronic kidney disease (CKD).
What is the recovery phase of AKI and how long can it last?
The recovery phase of AKI can last weeks to months.
How can chronic kidney disease (CKD) develop from AKI?
CKD can develop if AKI results in a greatly decreased GFR, leading to progressive kidney disease.
When can a dog or cat be considered to have CKD resulting from AKI?
A dog or cat can be considered to have CKD resulting from AKI if they are persistently azotaemic 3 months after the resolution of AKI.
Why may a renal diet not be necessary for an animal with AKI in the first 3 months?
A renal diet may not be necessary for an animal with AKI in the first 3 months because the GFR may return to normal levels over that period.
How can repeated GFR estimation be helpful during the recovery phase of AKI?
Repeated GFR estimation can help determine if an animal’s kidney function is changing during the recovery phase of AKI.
What are common signs of acute kidney injury (AKI) in dogs and cats?
Common signs of AKI include lethargy, decreased appetite, vomiting, nausea, and decreased urine output.
Why is it important to determine if affected animals had access to nephrotoxins?
Determining if affected animals had access to nephrotoxins is important because many cases of renal AKI are related to toxin exposure.
What can palpation of the kidneys reveal during a physical examination of an animal with AKI?
Palpation of the kidneys can reveal if they are enlarged or irregular in outline.
What does palpation of the bladder during a physical examination of an animal with AKI indicate?
Palpation of the bladder can help determine if urine is still being produced.
Why is evaluating the volume and hydration status important when assessing animals with possible AKI?
Evaluating volume and hydration status is important to guide fluid therapy and prevent excessive volume of intravenous fluids in animals that cannot produce urine.
What are the indicators of AKI in non-azotaemic animals based on serum creatinine levels?
An increase in serum creatinine of 26.4 μmol/l or more over 48 hours suggests developing AKI, even if values are within the reference interval.
What is the significance of confirmed oliguria/anuria over a period of 6 hours in diagnosing AKI?
Confirmed oliguria/anuria over 6 hours is sufficient to diagnose AKI in non-azotaemic animals.
What does an increased anion gap in the blood imply?
It implies a large amount of another unmeasured anion in the circulation, such as ethylene glycol.
What are some concerns regarding the diagnostic accuracy of direct ethylene glycol tests?
There are questions over the diagnostic accuracy of these tests and they may give false positive results in ketotic patients.
What is the purpose of the grading scheme produced by IRIS for animals with acute kidney injuries?
To assess the severity of its presentation and provide a shared framework for clinical studies.
How is the grading scheme for acute kidney injury different from the clinical stages of chronic kidney disease?
Animals with acute kidney injury are expected to change grades as they progress, while animals with chronic kidney disease remain at a particular stage for some time before gradually progressing.
What is the key principle for treatment of acute kidney injury?
To intervene at the earliest possible moment to decrease the severity of the induction and extension phases.
What is more effective than treating acute kidney injury?
Prevention of potentially damaging insults.
What are some examples of specific treatments for different causes of acute kidney injury?
Ethanol or 4-methylpyrazole for ethylene glycol, amoxicillin/clavulanate followed by doxycycline for leptospirosis, antimicrobials based on culture and sensitivity for pyelonephritis, placement of a catheter for urethral obstruction, placement of a stent or bypass device for ureteral obstruction, and administration of synthetic prostaglandin misoprostol for NSAID toxicity.
What treatment is required if there is no apparent cause and specific factors have been treated?
Most animals will require supportive treatment.
What is the key consideration in providing hydration and volume support for animals with acute kidney injury?
Balancing fluid administration to meet maintenance requirements without causing overhydration in anuric/oliguric patients.
What are some risks associated with overhydration in animals with kidney injury?
It can worsen kidney injury, cause hypertension, and lead to complications such as pulmonary edema.
How can the hydration and volume status of animals with acute kidney injury be monitored?
Through clinical examination of skin turgor and eyes for chemosis, frequent weighing to check for weight gain, and matching input to output in urine production.
What is one insult that can cause papillary necrosis?
Overdose of non-steroidal anti-inflammatory drugs (NSAIDs)
How do non-steroidal anti-inflammatory drugs (NSAIDs) disrupt the prostaglandins in the kidney?
They disrupt the prostaglandins that normally facilitate blood flow to hypoxic regions of the kidney
What do the afferent and efferent arterioles regulate in the glomerular capillaries?
The pressure of blood
What is the purpose of the pressure difference from the capillaries to the Bowman’s space?
To provide a gradient for filtration of blood plasma
How does constriction of the afferent arteriole affect pressure in the glomerulus?
It decreases pressure in the glomerulus by preventing the entry of blood into the glomerular capillaries
How does constriction of the efferent arteriole affect the pressure gradient between the glomerular capillaries and Bowman’s capsule?
It maintains the pressure gradient by limiting the exit of blood out of the glomerulus
What does the glomerular filtration rate (GFR) measure?
The volume of glomerular filtrate produced per unit time
What does a decrease in GFR indicate about kidney function?
The ability to filter blood and produce urine also decreases
What is the GFR an average of?
The individual GFRs of the nephrons in both kidneys
What is the product of afferent arterial flow and filtration fraction (FF)?
The GFR
What happens to the GFR if the afferent arterial flow decreases due to hypovolemia?
The GFR will drop
What happens to the GFR if the filtration fraction (FF) drops due to decreased glomerular permeability?
The GFR will drop
What governs the filtration fraction?
The balance of Starling forces
What are the chief Starling forces in the glomerular capillaries?
Difference in hydrostatic pressure and difference in capillary osmotic pressure
What is the main determinant of colloid osmotic pressure (COP)?
Blood protein concentration
What determines the reflection coefficient of the glomerulus?
The area of the glomerular capillaries and the permeability of the capillaries
What happens to the GFR if there are fewer glomerular capillaries?
The GFR will drop
What happens to the GFR if the capillary walls become less permeable?
The GFR will drop
What are critical determinants of the hydrostatic pressure gradient along the glomerular capillaries?
Constriction of the afferent and efferent arterioles
In the presence of aldosterone, what happens to sodium and potassium?
Sodium is reabsorbed and potassium is excreted into the urine.
What are the consequences of aldosterone deficiency in Addison’s disease?
Dogs with hypoadrenocorticism often present with hyperkalaemia and hyponatraemia.
How does the movement of potassium into cells help regulate potassium levels?
It provides a temporary buffer to prevent a spike in blood potassium concentration.
Where is potassium filtered and reabsorbed in the kidney?
Potassium is filtered in the glomerulus and reabsorbed in the proximal convoluted tubule (PCT) and loop of Henle.
How is potassium excreted in the distal convoluted tubule (DCT)?
Potassium can be excreted as sodium is reabsorbed using a channel activated by aldosterone.
What happens when there are severe reductions in GFR in kidney disease?
Potassium cannot be excreted as quickly as it is ingested, causing hyperkalaemia.
What can happen in some animals with CKD in terms of potassium excretion?
Dysfunction of the renal tubules may prevent reabsorption of potassium, leading to chronic hypokalaemia.
How is phosphorus regulated in the kidney tubules?
Reabsorption of phosphorus is closely controlled by the concentrations of parathyroid hormone (PTH) and fibroblast growth factor (FGF)-23.
What increases the secretion of PTH and FGF-23 in regards to phosphorus excretion?
Phosphorus forms a feedback loop by increasing the secretion of PTH and FGF-23.
What is the main regulator of calcium concentration in the extracellular fluid?
Parathyroid hormone (PTH)
Where is calcium reabsorbed in the kidney?
Calcium is reabsorbed in the proximal convoluted tubule (PCT) and loop of Henle.
What does PTH do to increase reabsorption of calcium?
PTH acts to increase blood calcium concentration by increasing intestinal, dietary, and bone reabsorption of calcium.
What do the kidneys regulate in addition to removing toxic products?
The kidneys regulate the normal osmolality and electrolyte composition of the extracellular fluid, as well as the total volume of this fluid.
What is the distribution of total body water among different compartments?
Approximately two thirds is intracellular fluid, one quarter is blood plasma, and almost all of the remainder is interstitial fluid between cells.
What is the difference between hypovolaemia and dehydration?
Hypovolaemia refers to reduced volume of fluid in the circulatory system, while dehydration refers to overall body water loss.
What treatment should be administered to restore cardiac excitability in sinoventricular rhythm?
Calcium gluconate 10% should be administered slowly IV over 15-30 minutes.
What is the main goal of correcting hyperkalaemia?
Re-establishing urine output and allowing intracellular movement.
How can intracellular movement be stimulated during the correction of hyperkalaemia?
Administering fluid with 5-10% dextrose and/or soluble insulin.
What should be monitored closely in non-diabetic animals receiving insulin during the correction of hyperkalaemia?
Blood glucose concentration.
How can nausea and inappetence be treated in animals with AKI?
Treatment with maropitant, gastroprotectants, and administration of food by oesophagostomy or naso-oesophageal tube.
What should be considered when administering food by oesophagostomy or naso-oesophageal tube to animals with AKI?
The solutions contribute to the total fluid input and potential overhydration.
What is the polyuric phase of AKI characterized by?
Severe polyuria as glomerular filtration occurs before tubular function has recovered.
What electrolytes may need to be supplemented in intravenous fluids for animals in the polyuric phase of AKI?
Sodium and potassium.
How can grape and raisin ingestion potentially cause AKI in dogs?
The toxin responsible is unknown, and even small amounts can cause disease.
What initial signs may dogs show after ingesting grapes or raisins?
Vomiting and/or diarrhea.
What precautions should be taken in treating dogs with recent grape or raisin ingestion?
Monitoring serum creatinine concentration and urine specific gravity frequently in the first 48 hours.
What factors are associated with a poor outcome for dogs with AKI?
Failure to produce urine again, high creatinine level, anemia, and hypocalcemia.
What is the survival rate for dogs with leptospirosis-induced AKI?
Approximately 80%.
What is the difference between dehydration and hypovolaemia?
Dehydration refers to a decreased amount of total body water, while hypovolaemia refers to a decreased circulating blood volume.
Give an example to explain the difference between dehydration and hypovolaemia.
In the example of a dog that has lost a large amount of blood, it would be severely hypovolaemic but only mildly dehydrated.
What is the treatment approach for a severely hypovolaemic dog?
Rapid administration of large amounts of fluid, such as boluses of crystalloids or a blood transfusion.
Describe the hydration deficit correction approach for a dog with chronic kidney disease.
Slow correction of the hydration deficit over a period of many hours or days.
Which hormone regulates the osmolality of extracellular fluid?
ADH (anti-diuretic hormone)
Where are the specialised osmoreceptors located?
In the supraoptic nucleus of the hypothalamus.
What happens when the osmolality of extracellular fluid increases?
ADH is released, increasing the permeability of the DCT and CD to water, allowing reabsorption of large amounts of water.
What is the role of increased osmolality in activating thirst receptors?
It causes the animal to drink more water.
What can result from inappropriate ADH secretion?
Hyponatraemia (a decreased concentration of sodium in the blood).
Which enzyme is released by the macula densa in response to decreased flow of sodium and chloride ions?
Renin
What is the principal action of angiotensin II?
It increases reabsorption of sodium in the proximal renal tubule and causes absorption of water by osmosis, expanding the ECF volume.
What actions does angiotensin II have on the glomerulus?
It causes constriction of the efferent arterioles.
What is the purpose of angiotensin II’s action on the glomerulus?
To maintain a normal GFR (glomerular filtration rate) despite decreased renal flow.
Who is the module developer for Urology I in the Small Animal Medicine Distance Learning Module 17?
James Swann
What are the learning objectives for Urology I in the Small Animal Medicine Distance Learning Module 17?
- Describe how the kidney removes toxic substances from the blood. 2. Explain how the kidney regulates the osmolality and volume of the extracellular fluid. 3. Distinguish between hypovolaemia and dehydration. 4. Identify the hormones produced by the kidney and their major roles. 5. Identify the major diagnostic tests used to assess kidney function. 6. Describe the advantages and limitations of the major diagnostic tests for assessing kidney disease in small animals. 7. Explain how diagnostic tests can be used to distinguish between acute and chronic kidney diseases. 8. Give examples of new biomarkers that have been described in cats and dogs. 9. Describe the major causes of acute kidney injury (AKI). 10. Grade cases of AKI according to the IRIS guidelines. 11. Outline a clinical approach to a case with suspected AKI. 12. Explain the components of treatment for an animal with AKI.
What will be covered in the first section of the module?
Basic aspects of renal physiology, including how the kidneys handle water and substances dissolved in the blood, maintaining the normal volume and concentration of solutes in the extracellular fluid, and the hormones produced by the kidneys.
What is the renal artery a direct branch of?
The abdominal aorta.
What are the two types of arteries formed from the renal artery within the kidney?
Interlobar arteries and arcuate arteries.
What form a tuft of capillaries within the kidney?
The afferent arterioles that enter the glomerulus.
What does the efferent arteriole form when it leaves the glomerulus?
Multiple peritubular capillaries, which are closely associated with the renal tubules.
What do the peritubular capillaries ultimately form?
Renal venules, which drain into the renal vein.
What happens if there is a reduction in blood flow to the renal artery?
The whole kidney may experience ischaemia since the kidney has no collateral blood supply.
What makes the central parts of the kidney vulnerable to ischaemia?
The progressive branching of blood vessels means that they become relatively hypoxic.
What can be seen on ultrasound scans of older animals’ kidneys due to hypoxia?
Old renal infarcts.
What is azotaemia?
Azotaemia is a syndrome of clinical signs occurring due to severe kidney disease.
Is uraemia a clinical diagnosis related to biochemical values?
No, uraemia is a clinical diagnosis made in azotaemic patients and is not related to biochemical values.
What is SDMA?
SDMA is an alternative biochemical measurement used to estimate kidney function.
How is SDMA related to bodyweight and muscle mass?
SDMA is not related to bodyweight or muscle mass in the same way as creatinine.
What were the major claims made about SDMA?
The major claims for SDMA were: 1. It detects decreased kidney function with more sensitivity than creatinine. 2. An increased SDMA can predict which animals will go on to become azotaemic later.
What was the correlation between GFR and SDMA in dogs with hereditary nephropathy?
The correlation between GFR and SDMA in dogs with hereditary nephropathy was 0.95.
What were the findings about the association between GFR and SDMA/creatinine in dogs with CKD?
There was no difference in the association between GFR and either SDMA or creatinine in dogs with CKD or non-azotaemic dogs.
Can an increased SDMA concentration predict the onset of kidney disease earlier?
In dogs with X-linked nephropathy, SDMA increased sooner than creatinine but the average difference was only 4-5 weeks.
How many dogs with post-mortem evidence of CKD had an increased SDMA before creatinine increased or euthanasia?
17 out of 19 dogs had an increased SDMA on average 9.8 months before creatinine increased or the dog was euthanised.
What is the main issue with the study on increased SDMA in dogs with post-mortem evidence of CKD?
The study is problematic because 10 dogs were euthanised without increased creatinine concentration, making it unclear if the increased SDMA had clinical significance.
Can an increased SDMA predict the onset of azotaemia in some dogs?
Yes, SDMA might predict the onset of azotaemia effectively in some dogs.
Did increased SDMA always correspond with clinically important kidney disease in the study of cats?
No, increased SDMA appeared to precede the onset of azotaemia or decreased GFR, but cats varied in the underlying nature of their kidney disease.
What is the most common cause of pre-renal acute kidney injury?
Prolonged pre-renal insult (ischaemia leading to infarction)
What is the main cause of renal acute kidney injury?
Damage to the renal tubules (acute tubular necrosis)
What are the two types of damage that can cause renal acute kidney injury?
Ischaemic (related to prolonged hypoperfusion) or toxic (exposure to nephrotoxins)
Which type of acute kidney injury is caused by obstruction to urine flow?
Post-renal acute kidney injury
What are some common causes of post-renal acute kidney injury?
Urethral obstructions, ureteroliths
What are some factors that increase the risk of developing hospital-acquired acute kidney injury?
Hypovolaemia/dehydration, nephrotoxic drugs, procedures that decrease renal blood flow or cause renal insult
Which phase of acute kidney injury is characterized by the first cellular damage occurring in the kidney?
Initiation phase
During which phase of acute kidney injury is the AKI clinically detectable and oliguria/anuria occurs?
Extension phase
During which phase of acute kidney injury is there irreversible damage but it is not progressing?
Maintenance phase
Which phase of acute kidney injury is characterized by signs of repair and the animal becoming extremely polyuric?
Recovery phase
What can a doubling of creatinine concentration within the reference interval represent?
A serious deterioration in kidney function.
Why can creatinine concentration vary between breeds?
Because production of creatinine is proportional to the animal’s muscle mass.
How do animals with muscle wastage affect the accuracy of creatinine for evaluating kidney function?
It decreases the accuracy because less creatinine is being produced.
How can animals with CKD and a low body condition score affect the measurement of serum creatinine concentrations?
Measured serum creatinine concentrations may underestimate the filtration capabilities of the kidneys.
What is the effect of small amounts of creatinine secretion in the renal tubules of male dogs?
It can affect the estimation of GFR if urine creatinine measurements are included.
How does a large drop in GFR affect serum creatinine concentration?
A large drop in GFR needs to occur before there is any change in serum creatinine concentration.
Is there a preclinical period for animals with kidney disease before any change in creatinine occurs?
Yes, there is potentially a long preclinical period before any change in creatinine.
How does the relationship between GFR and creatinine concentration change after creatinine increases above the reference interval?
Even large increases in GFR may not be of any clinical significance.
What substances can interfere with the optical detection of creatinine?
Glucose, ketone bodies, some antibiotics, haemolysis, hyperbilirubinaemia, and lipaemia.
Why is it recommended to fast animals for measurements of creatinine?
Because the serum creatinine concentration may be increased transiently after eating, especially after eating meat.
What is urea?
Urea is a nitrogenous waste product made from ammonia in the liver.
How is blood urea concentration different from creatinine concentration?
Blood urea concentration is more variable than creatinine and is affected by a larger number of other factors not related to kidney disease.
What could an increased urea on a biochemical sample be related to?
It could be related to kidney disease, gastrointestinal haemorrhage, or recent feeding.
What does azotaemia represent?
Azotaemia represents evidence of kidney dysfunction, which could be pre-renal, renal, or post-renal.
What is the difference between azotaemia and uraemia?
Azotaemia refers to a consistently increased creatinine concentration with or without increased urea, while uraemia refers specifically to an increased urea concentration in the absence of increased creatinine.
What is the rate at which intravenous fluids can be received?
0.5 ml/kg/hour
Why can intravenous fluids be received at a rate of 2.5 ml/kg/hour?
To reflect urine output + amount lost from insensible losses
What is one requirement to adopt the approach of adjusting fluid rate?
Placing a urinary catheter with a collection system
How often should the volume of urine be measured to adjust the fluid rate?
Every 2-4 hours
What is one indication for haemodialysis?
Severe overhydration
How does haemodialysis remove excess fluid?
By osmosis as the blood is filtered
What is the suggested initial bolus dose of furosemide for attempting to restore urine output?
2 mg/kg IV
What is the main role of furosemide?
To increase urine output to correct electrolyte abnormalities
What is the suggested dose of mannitol to increase urine output?
0.5-1 gram/kg over 15-20 minutes
When should mannitol be used with caution?
In patients that are overhydrated or dehydrated
Is there evidence that the use of diuretics improves outcome in animals with AKI?
No
Was the use of dopamine for AKI in dogs and cats recommended?
No
What parameter may cause severe physiological disturbances in animals with oligoanuric AKI?
Serum potassium concentration
What ECG changes are associated with hyperkalaemia?
Small, wide, or absent P wave and a wide QRS complex
What is the progression of ECG changes associated with hyperkalaemia?
Progressing to a…
What are the poor prognostic markers for cats with concurrent systemic diseases?
Hyperkalaemia, Anaemia, Low body temperature at presentation
What are the signs of shock in cats with concurrent systemic diseases?
Neurological or respiratory signs
In which year was the Symmetric Dimethylarginine Assay Validation published?
2015
Which biomarker was evaluated for the early detection of chronic kidney disease in dogs?
Symmetric Dimethylarginine
What is the diagnostic value of Symmetric Dimethylarginine, cystatin C, and creatinine for detecting decreased glomerular filtration rate in dogs?
Comparison
Which substance was used to compare serum iohexol clearance, serum SDMA concentration, and serum creatinine concentration in non-azotemic dogs?
Iohexol
What is a possible cause of decreased glomerular filtration rate in dogs?
Chronic Kidney Disease
In which year was the study conducted on serum concentrations of Symmetric Dimethylarginine and creatinine in dogs with naturally occurring Chronic Kidney Disease?
2016
Which kidney function biomarkers were compared in cats with Chronic Kidney Disease?
Symmetric Dimethylarginine and creatinine
What is a masked Chronic Kidney Disease in cats?
Chronic Kidney Disease in cats with Hyperthyroidism
What effect does boric acid have on bacterial culture of canine and feline urine?
Unknown
In which year was the study on the effect of boric acid on bacterial culture of canine and feline urine conducted?
2011
What does GFR stand for?
Glomerular Filtration Rate
How is iohexol clearance used to estimate GFR?
It is injected intravenously and its clearance is measured as it is excreted into the urine.
In which clinical scenarios might it be helpful to measure GFR?
Estimating renal function before giving a potentially nephrotoxic drug, determining kidney recovery after acute injury, if other parameters are unreliable.
What are the factors that can affect GFR?
Size, age, breed, and hydration status.
What is the normal range of GFR in cats and dogs?
1.8-2.1 ml/kg/min
What does a normal GFR measurement suggest about kidney function?
The kidneys are filtering blood appropriately in the glomeruli.
How does urea and creatinine help assess kidney function?
Increased serum concentration indicates impaired kidney function.
What is the relationship between creatinine and muscle mass?
Creatinine production is proportional to muscle mass.
What is the significance of Fanconi syndrome in relation to GFR?
Affected animals have normal GFR but a defect in reabsorption of certain substances in the proximal convoluted tubule.
What are the limitations of using creatinine as a measure of kidney function?
Creatinine increase is an insensitive measure and significant loss of kidney function is needed for it to rise above the reference interval.
What happens to the GFR when the efferent arteriole is moderately constricted?
The GFR increases due to an increase in the hydrostatic pressure gradient.
What happens to the GFR when the efferent arteriole is extremely constricted?
The GFR may decrease or stay the same compared to baseline due to an increase in colloid osmotic pressure gradient.
