Term 5 Week 13 Renal

What are some presenting complaints for CKD

Not doing right

Weight loss

Loss of muscle mass

Hyperoxia

PUPD

What is the degree of illness, history, kidney size/shape, rbc, K, weight and muscle mass of an animal with AKI

Degree of illness: symptoms more severe for degree of azotemia

History: lethargy, vomiting

Kidney size/shape: normal to large ± painful

Rbc: Normal or decreased (regenerative)

K: normal to high

Weight and muscle mass: no change

What is the degree of illness, history, kidney size/shape, rbc, K, weight and muscle mass of an animal with CKD

Degree of illness: symptoms less severe for degree of azotemia

History: PUPD, weight loss

Kidney size/shape: small, irregular BKLK (big kidney little kidney)

Rbc: non-regen anemia

K: low in cats, mild hyperkalemia in dogs

Weight and muscle mass: weight and muscle loss

Is CKD an emergency presentation

No

What is acute on chronic kidney dz

An acute injury on the already CKD so you must tx the acute injury and observe recovery

Explain FGF 23 and what it is used for

FGF 23 is an early marker for CKD in cats

FGF-23 is released by bone cells in response to increased phosphorus levels. SOOOO FGF-23 increases early in CKD as a compensatory mechanism to maintain normal serum phosphorus.

A cat can have increased FGF 23 and still normal serum P so that why it is a good early marker

What is the most important sign of CKD

Weight loss

What is a GFR study

Injection of an iodinase compound that the kidneys should excrete all → if remnants that means there is decreased GFR

It picks up less than 40% nephron loss

What are presenting complains of AKI

Vomiting

Diarrhea

Inappetence/anorexia

Lethargy

Collapse

How much of the nephrons are gone in CKD

75%

What helps stage kidney disease

IRIS (needs serial SDMA and creatinine findings)

How do you measure decreased GFR

BUN and creatinine- increase with 75% reduction in GFR

Isosthenuria- 60% reduction in GFR

SDMA- 25-40% kidney function loss

FGF 23- new marker for CKD early detection in cats

What is the problem with measuring SDMA

You cannot differentiate acute from chronic or pre-renal/renal/post-renal kidney disease

What can increase BUN that is not kidney disease

High protein diet or GI bleed

Explain GFR and creatinine

Initial drop in GFR only increases crea a little but as GFR gets lower and lower the same drop in GFR will increase crea a lot

A small increase in crea near the upper end of RI is IMPORTANT

Changes of what level of crea can be seen with AKI

Crea >0.3mg/dl

Explain pre-renal azotemia

GFR is decreased because of decreased blood flow to kidneys

Explain renal azotemia

GFR is decreased because of nephron loss

AKI or CKD

Explain post-renal azotemia

GFR is decreased because of backpressure of urine in nephrons

Quickly leads to renal azotemia

Ex. blocked cat

What is the most common congenital kidney dz in dogs

Renal dysplasia

How do you approach an AKI case

Stabilize the pt

Restore perfusion to the kidney

Investigate for underlying causes of AKI

Tx case

What USG can a cats urine go up to if they are really dehydrated

Can go as high as 1.085 (want it really high in cats to tell the kidney is working)

For dogs can go 1.030-1.040

What are biomarkers that don’t differentiate between acute/chronic/pre-renal/renal

BUN, crea, SDMA

What is the biomarker for acute tubular injury

Urine cystatin B

What is urine cystatin B

A small intracellular protein found in cells throughout the body, including renal tubular epithelial cells.

• Normally, it is present inside cells.

• When renal tubular cells become damaged, they release cystatin B into the urine.

• Increased urinary cystatin B suggests active tubular cell injury.

Urinary cystatin B is a marker of kidney injury, not simply kidney function.

Why should you be careful of fluids in kidney patients

Do not want to overload their kidneys that aren’t function which causes more damage

DONT flush the kidneys

Will animals recover from AKI

Depends on the extent of damage to the basement membrane

With mild injuries improvement can happen quickly

In severe injuries it may take > 8 days to see IF recovery will occur or not

What are the 3 categories of AKI

1) Hemodynamic AKI- renal hypoperfusion → renal injury

2) Intrinsic renal injury- like toxin, infectious, immune mediated

3) Obstructive AKI- obstruction leads to an AKI that resolves with unblocking (ureters or urethra)

How do you get secondary AKI from a urinary obstruction

Pressure builds up backwards affecting the kidneys and damaging the glomerulus

What percentage of dogs recover from AKI

75%

An animals is automatically what IRIS stage with an AKI

Stage 1

What are etiologies of AKI using the VITAMIN-D scheme

V: thrombus, prolonged decreased perfusion

I: pyelonephritis, lepto, tick-borne

T: exogenous, endogenous

A: immune mediated glomerulonephropathy

M: post-renal (ureteral obstruction)

I: inflammatory (pancreaitis, spesis, acute hepatitis)

N: neoplasia (carcinoma, lymphoma)

D: congenital/genetic (amyloid)

What is fanconi syndrome and how do dogs get it

Disorder of the kidney's proximal tubules that causes essential substances—such as glucose, phosphate, amino acids, bicarbonate, and electrolytes—to be wasted in the urine instead of being reabsorbed into the bloodstream

From eating jerky treats

What are the bad casts

Granular

Why is it important to check blood pressure in kidney patients

80% of the time AKI animals with have hypertension

Keep this in mind with fluid therapy

What is the most common renal tumor in cats

LSA

What is the most common renal tumor in dogs

Carcinoma

What are the other less common neoplasias of the kidney

HSA

Leiomyosarcoma

Nephroblastoma

Which systemic dz in cats can cause renomegaly

FIP

How can you dz a renal neoplasia

FNA for LSA

True-cut biopsy

Laparoscopic

Sx

What is the tx for feline renal LSA

CHOP or COP

Careful with doxo until azotemia resolved though

62% respond

What are common causes to urinary obstruction in the renal pelvis and or ureteral

Ureterolith

Stricture

Blood clot (trauma)

Infectious- secondary to pyelonephritis

What are common causes to urinary obstruction in the urethra

FLUD, calculi, neoplasia

What happens in a pyelogram

Dye is injected into the renal pelvis and it looks for if there is an obstruction

What is the most common cause of infectious dz to the kidney

Pyelonephritis with E. coli

What should you always perform in new renal azotemia

Culture of urine

What are the options for testing lepto

PCR of blood and urine

Titer test (microscopic agglutination test/MAP)

What are the challenges in lepto testing

Time infected to time when CS appear is variable

Bacteremia occurs early in infection

Bacteruria occurs later in infection but is cyclical and variable

Antibodies are made 7-14 days after infection

Vx produce antibodies but even vx dogs can get lepto

What are the pros and cons of microscopic agglutination test (MAP) in the dx of lepto

Pros: gold standard when paired, up to 50% of cases are missed with just one

Cons: send to lab, takes 5-7 days, vx interference, titers rise 7-14 days post infection, serovar cross-reactivity

What are the point of care tests for lepto

Idexx snap (positive= titer 1:400 or higher)

Witness test (IgM only- less vx interference)

What are the pros and cons of blood and urine PCR on lepto

Pros: if positive confirms, serovar specific

Cons: bacteremia phase is short, bacteruria is intermittent and cyclical, if abx given can make it neg, send to lab and takes 5-7 days

What does the presentation and outcome of AKI depend on

Cause of insult

How much initial pathological damage is done

How much further damage is caused during the extension phase

How great the inflammatory response is

When the dx and clinical intervention occurred

How much additional organ damage or multisystemic dz has occurred

What can happen with creatinine levels in late CKD

Can plateau out

What classifies grade I IRIS AKI

Blood creatinine <1.6mg/dl (<140umol/l)

Nonazotemic AKI: documented AKI, progressive nonazotemic increase in blood creatinine, measure oliguria or anuria

What classifies grade II IRIS AKI

Blood creatinine 1.7-2.5 mg/dl (141-220 umol/l)

Milk AKI: documented AKI and static or progressive azotemia, progressive azotemia increase in blood creatinine within or volume responsiveness)

What classifies grade III IRIS AKI

Blood creatinine 2.6-5.0 mg/dl (221-439 umol/l)

Moderate to severe AKI: documented AKI and increasing severities of azotemia and functional renal failure

What classifies grade IV IRIS AKI

Blood creatinine 5.1-10 mg/dl (221-439 umol/l)

Moderate to severe AKI: documented AKI and increasing severities of azotemia and functional renal failure

What classifies grade V IRIS AKI

Blood creatinine >10 mg/dl mg/dl (221-439 umol/l)

Moderate to severe AKI: documented AKI and increasing severities of azotemia and functional renal failure

Why is it good to place a urinary catheter in AKI patients

To measure urine output

What are the sub-grades for AKI according to IRIS

Non-oliguric (NO)

Oligo-anuric (O)

Requiring renal replacement therapy (RRT)

What happens with GFR and creatinine

GFR falls and creatinine goes up

Creat measurements in grading are proxy for GFR

What can IRIS grading tell you about prognosis

Allows tracking of progression and recovery, allows some degree of prognostication, lower grade do better if don’t progress

Decreasing grade in response to tx

Sub-staging

What can you see in CBC/Chem/UA with AKI

Leukocytosis (infectious cause)

Azotemia (stage)

Serum calcium level are normal to low in the absence of hypercalcemia induced AKI

Hypocalcemia may occur in animals with EG toxicity

Hyperphosphatemia may be present the degree of which reflects the severity of renal dysfunction

UA shows isosthenuria with AKI

Mild to moderate glucosuria may be seen with acute tubular damage

Urine pH is usually acidic although it may be alkaline in the presence of some bacterial urinary tract infections

The urine sediment should be carefully examined for the presence of casts, WBC, bacterial, crystals

What can sodium concentrations be in AKI

Low, normal, or high depending on degree of vomiting and or diarrhea and any prior therapy

What potassium concentration can be seen with AKI

Hyperkalemia in oliguric or anuric phase of AKI

What should be performed in all cases of pylonephritis

Urine culture

How can you dx ethylene glycol

Serum EG levels can be measured if 1st few hours after ingestion

Severe metabolic acidosis with elevated anion gap

Large numbers of calcium oxalate crystals in urine sediment

How can you dx cholecalciferol toxicity

Causes hypercalcemia

Can measure serum cholecalciferol levels

When is renal biopsy indicated

When the results would change therapy or prognosis

What are principles of fluid therapy for AKI patients

Correction and maintenance of the animals hydration, acid-base, and electrolyte status are the cornerstones of tx for AKI

IV fluid therapy is indicated for all hospitalized patient with AKI dx

Frequent monitoring of various parameters is key to making appropriate adjustments in therapy

How do you monitor fluid therapy in AKI patients

Clinical assessment of hydration

Body weight

Capillary refill

Heart and respir rate

Arterial blood pressure

Packed cell volume and plasma total solids

Serum chem (BUN, crea, sodium, potassium, chloride, phosphorus)

What does MDO mean in fluid therapy

M= maintenance (replenish normal intake)

D= deficit (replenish hydration)

O= ongoing losses

What is the daily maintenance fluid requirement for most mammalian species

50 ml/kg/day

What is the daily maintenance fluid requirement for cats

40 ml/kg/day

How long do you want to work for to replenish fluids in cats vs other species with AKI

Over 24 hours in cats

4-6 hours in dogs

What fluid type should be administered if hyperkalemia is present or suspected because of oliguria or anuria

K free fluid such as 0.9% sodium chloride

What can 0.9% sodium chloride cause

The chloride can cause glomerular hypertension (plasma A is better in that case)

What can continued administration of fluids high in sodium cause

Hypernatremia (especially in cats)

Use fluids with lower sodium in these cases

What are the cons of an indwelling urinary cath

Risk of ascending infection

Need sedation/GA to place

How much is 1 kg or 1 gm in ml

1 kg= 1000ml

1 gm= 1 ml

What should urine output be

1-2 ml/kg/hr

How much do you give for a shock bolus

1/4th maintenance (40-50 ml/kg/day) over 10 minutes

What is included in supportive tx for AKI

Fluid therapy

Manage oliguria/anuria

Manage polyuria

Correct acid/base abnormalities

Correct electrolyte abnormalities

Adjust drug dz

Manage vomiting

Manage hypertension

Nutritional management

What is the antidote for ethylene glycol toxicity

Everclear

When can you induce vomiting and give activated charcoal in the timeline of toxicity

Within hours of presentation

How do you tx post renal obstruction for AKI

Urethral: stabilize and unblock

Renal pelvis and or ureter: surgical as soon as possible once stable

What can IV lipid infusion be used to tx

Ivermectin toxicity in MDR1 def dogs

What are good options for empiric tx of infectious cystitis

Beta-lactams

Fluoroquinolones

TMS

Nitrofurantoin

What are good options for empiric tx of infectious pyelonephritis

Fluoroquinolone

Ampicillin

3rd gen cephalosporin

Aminoglycoside

How can you tx gram ± pyelonephritis

Tx for 2 weeks with enrofloxacin or 3rd gen cephalosporin, IV if septic

Adjust based on C&S

How can you tx lepto

2 weeks with doxy

Start with IV ampicillin if too ill to start PO doxy

What are some prognostic factors for AKI

Oligoanuria

Cats: hypothermia on presentation

Better: infectious, obstruction

Worse: toxins, glomerular

Why does proteinuria matter

Damages renal tubules, leads to progressive decreased GFR

Treating proteinuria is one of the very few tx we have evidence basis for that improves outcomes for kidney patients both CKD and glomerular

What does proteinuria from glomerular dz do the the prognosis

It changes it (probs worse)

What causes pre-glomerular pre-renal azotemia

Abnormal, small proteins in blood

What causes transient renal proteinuria

Abnormal filtering due to increased glomerular pressure from other factor (hypertension or cushings)

NOT A PRIMARY RENAL DZ

What causes pathologic renal proteinuria

Glomerular or tubular dz

What causes post-renal proteinuria

LUT- protein added to urine after kidney (UTI, stones, neoplasia)

What are some localizing tests for proteinuria

CS: LUT, UUT, hypoalbumin, azotemia, other dz

Urine sediment: WBC, RBC, bacteria if LUT origin

Bence-Jones/light chain

What is bence-jones light chain

Bence Jones proteins are monoclonal free immunoglobulin light chains (kappa or lambda) produced in excess by neoplastic plasma cells and excreted in the urine. In veterinary medicine, they are primary diagnostic markers for multiple myeloma, extramedullary plasmacytomas, and related B-cell malignancies in dogs and cats