Transcript Diseases of Urinary System

Diseases of Urinary System
Urinary System
• Anatomy/Location
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Kidneys
Ureters
Bladder
Urethra
• Function
– Remove waste
– Maintain homeostasis
• acid/base
• electrolytes
• fluid balance
– Hormone production
• erythropoietin
Urinary System
– Infections usually due to ascending organism
– Usually resistant to bacterial infection
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Frequent urination flushes bacteria
Urethral/ureteral peristalsis
Glucosaminoglycans in mucosa
pH
Feline Cystitis
Cause unknown; virus suspected; usually
not bacterial; recurrence likely
Self-limiting (7-10 d), so any appropriate
treatment appears to help
• Signs
– Frequent urinations (sm vol)
– Hematuria
– Dysuria
– Inappropriate urination (sinks,
tubs are a favorite)
• Dx
– Urinalysis/culture to r/o bacteria
as cause
– X-rays to r/o calculi; contrast
studies show thickened wall
Feline Cystitis
• Rx
– Avoid unnecessary antibiotics
– Change diet from dry to moist
• Salt food to ↑ water intake
– Reduce stress from other cats,
kids, etc (hiding places)
• Client info
– Disease is self-limiting
– May be recurring problem
– No definitive cure
– Reduce stress
Canine Cystitis (Bacterial Cystitis)
• Signs
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↑ frequency of urination
Hematuria
Dysuria
Cloudy urine; abnormal color
Frequent licking of urethral area
• Dx
– Urinalysis: ↑WBC’s, bacteria
– Urine culture/sensitivity
• Collect by cystocentesis(?)
– Mid-stream collection
Canine Cystitis (Bacterial Cystitis)
• Rx
– Avoid unnecessary use of indwelling urinary catheters
• Use closed system
– Antibiotics according to sensitivity
• Treat acute infections x 10-14 d
• Subsequent infections x 4-6 w
– Avoid trauma to urinary tract during surgery
• Client info
– Many uncomplicated urinary tract infections resolve without Rx
– Give antibiotics as directed for the time prescribed
• Relapses are common due to inadequate treatment
– Prostate may be source of recurring infections in male dogs
– Urine cultures should be repeated during treatment to assess
effect
Close system
Feline Uroliths and Urethral Plugs
“Plugged” male cats are commonly seen in SA practice
Will be fatal if not relieved
• Uroliths (bladder stones) found anywhere in urinary tract
– Formed from minerals in diet
– Some are radiopaque (Ca++ oxalate, urate, struvite) and can be
seen on x-ray
– Some are radiolucent and require double contrast (air, dye)
• Uroliths damage bladder, making it more susceptible to
bacterial infection, hematuria
• Uroliths can form plugs in urethra of males
– Bladder will fill with urine
– Kidneys will stop working
– Blood/body will become toxic (azotemic)
Feline Uroliths and Urethral Plugs
• Signs (more severe if obstruction has occurred)
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Hematuria
Dysuria/ frequent urination
Urinating in strange places (sink, tub)
Straining to urinate
Vomiting
Collapse, death
Feline Uroliths and Urethral Plugs
• Dx
– Palpation of bladder (obstructed is full and tight)
– X-rays may show uroliths on routine films
• Double contrast studies may be indicated
– Ultrasonography can locate position of urolith
– Urolith analysis to determine its constituents
Double contrast cystogram
(with stones)
pneumocystogram
US of bladder stone
Feline Uroliths and Urethral Plugs
• Rx
– Medical treatment (chronic, non-obstructed)
• Dissolve struvite uroliths (most common; ~60%) by acidifying
urine and feeding diet low in Mg (Vit C, S/D)
– Should resolve in 4-8 wk
– Re x-ray, and continue diet 1 mo after uroliths gone
• Antibiotics according to culture/sensitivity
Feline Uroliths and Urethral Plugs
• Medical treatment (obstructed)
– Anesthetize (short acting)
• ***USE LESS ANESTHESIA IN AZOTEMIC CATS***
– Pass ‘silver needle’ (soft metal, atraumatic) or Tom cat catheter
and back flush
– Sew catheter in place for 1-3 d (??)
Feline Uroliths and Urethral Plugs
• Surgical treatment (chronic obstructers)
– Perineal urethrostomy
• New opening for urethra is created proximal to narrowing
• Urethral opening looks like a female
• E collar till sutures removed
Urolithiasis (Canine)
Smaller incidence in dogs than cats
Uroliths damage mucosa of urinary tract making it susceptible to infection
Uroliths can obstruct urine flow in males
• Signs
– Dysuria
– Hematuria
• Dx
– Urinalysis
• Crystalluria
• Hematuria
• ↑ bacteria
– X-rays (double contrast ?)
– Do stone analysis
Canine Uroliths
Urolith
Struvite
Breed
min sch
Sex
female (80%)
Contributing factors
alkaline urine
Rx
acidify urine
bacteria→urease→↑pH
minerals (diet)
antibiotics
Only Hill’s s/d (dissolve)
(Mg Ammonium Phos (MAP—triple phosphate)
(~50% of all stones)
cats
↑Na, ↓protein (ammonia)
↑H2O intake (flush stones
acidy urine
Calcium Oxalate
(30-50% of
all stones)
cats
males
min sch
Lhasa, Yorkie
min pood
Shih Tzu
diet high in protein
hypercalcemia
Cushing’s Dis
use of cortisone
acid urine
Sx removal (only Rx)
↓ dietary Ca (milk)
↓ dietary Na
Hill’s u/d, w/d, k/d
Urates
Dalmatians males
E bulldogs
min schnauzer
Shih Tzu
York terrier
↑ uric acid from kidneys
acid urine
Allopurinol
(gout in humans)
K+ Citrate (↑ urine pH)
Hill’s u/d, ↑ dietary sal
Canine Uroliths
Struvite
Calcium Oxalate
Urate
Type of stone cannot be determined by appearance; chemical analysis is required
Urolithiasis (Canine)
• Rx
– Medical (objective is to dissolve stones)
• ↓ mineral intake in diet→↓ minerals in urine
• ↑ urine acidity (nor for urates)
– Vit C
– methionine (Methogel®)
• ↑ urine output
– Add salt to diet
– Furosemide
• Antibiotics for bacterial infection
– Surgical removal
• Some uroliths are not amenable to Medical Rx
• However, the cause of uroliths must be dealt with medically (prevention)
Urolithiasis (Canine)
What do you see? How many?
• Client info
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Special diet may be required for life-time
Table scraps/treats should be limited
Long-term antibiotics may be required
Uroliths may recur at any time
Always provide plenty of fresh water
Allow plenty of bathroom time and frequency
Urolithiasis (Canine)
What do you see?
Flush toward bladder (8 times)
Saline flush
One in bladder, 2 in urethra
Urolithiasis (Canine)
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What do you see?
Urolithiasis (Canine)
What do you see?
Urolithiasis (Canine)
Renal Failure
• ~20% of CO
– Filtered by renal corpuscle
– Reabsorbed by kidney tubules
– Waste excreted as urine
• Renal Failure due to:
– ↓ blood flow (hypoperfusion)
– Damage to nephron
Acute Renal Failure
An abrupt decrease in glomerular filtration → azotemia (↑ N toxins in blood)
• Causes
– Damage to nephron (damaged nephrons do not regenerate; other nephrons
will hypertrophy)
Any part of nephron may be damaged (when 1 part of nephron is lost, it is all lost)
• Nephrotoxic drugs
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Aminoglycosides (gentamicin, streptomycin)
Cephalosporins (cephalexin, cephalothin)
Sulfanamides (Albon, Di-Trim)
Chemotherapeutic agents
Antifungal medications
Analgesics (acetaminophen)
Anesthetics (methoxyflurane [Metafane])
Ethylene glycol (antifreeze)
• Infections (nephritis)
• Immune-mediated diseases (Glomerulonephritis)
– ↓ Renal perfusion
• Shock
• Hypovolemia/dehydration
• Hypotension
Acute Renal Failure
• Signs (non-specific)
– Kidneys are enlarged and painful on palpation
– Signs of azotemia
• Anorexia, dehydrated
• Vomiting/diarrhea
• Weakness
– Fever
• Dx
– Urinalysis—urine sediment/casts; low sp grav (unable to
conc urine)
– CBC—dehydration (↑PCV), acidosis
– Chem panel
• ↑ BUN, Creatinine
• ↑K+, Phosphorus
Acute Renal Failure
• Rx (aim is to restore renal hemodynamics)
• Relieve tubular obstruction
• Discontinue any toxic drugs
– IV fluids (start with normal saline)
• Correct dehydration
• Correct acid/base (sodium bicarb) and electrolyte imbalance
– Diuretics to increase urine output
• Client info
– Renal function may never be like it was before injury
– Px is guarded
– Care must be taken to avoid events that may
precipitate further damage to kidney
• Appropriate diet
• Adequate water access
Chronic Renal Failure
Common in older pets; cats appear to be more affected than dogs
Irreversible and progressive decline in renal function (nephron damage)
• Progressive
– 1st function lost: Ability to concentrate urine
• PU, PD, nocturia
– Loss of ADH response
– Other functions lost: Ability to cleanse blood
• Azotemia (toxemia)
– Begins at ~75% of nephron loss
– ↑ BUN, Creatinine
• Anemia: erythropoietin secreted by kidneys
Chronic Renal Failure
• Signs
– Dull, lethargic, weak
– Anorexia, wt loss
– PU/PD cervical ventroflexion
• hypokalemia
– Sudden blindness
• Dx
– Acidosis
– Anemia
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↑ BUN, Creatinine
Hyperphosphatemia
Hypokalemia
Proteinuria
Chronic Renal Failure
• Rx
– Fluids for dehydration (IV, SQ)
– Potassium gluconate, calcium carbonate for electrolyte
imbalances
– Sodium bicarb for pH adjustment
– Diuretics (Furosemide)
– Hormones
• Epoetin
– Vit B supplements
• Client info
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CRF is progressive and irreversible
Rx is aimed at slowing its progress
SQ fluids at home are required to maintain hydration
Warm foods to improve palatability
Quality of life will decrease; euthanasia may have to be
considered
Urinary Incontinence
Loss of voluntary control of micturition
• Causes
– Neurogenic—loss of normal neural function causing a
paralyzed bladder
– Ectopic ureters
– Patient urachus
– Endocrine imbalance (after spay)
Urinary Incontinence
• Signs
– Urine leakage when pet is sleeping or exercising
– Perianal area of pet is aslways wet
– Concurrent urinary tract infection
• Dx
– Urinalysis
– X-rays/cystography
– Chem panel to r/o PU from endocrine disease
Urinary Incontinence
• Rx (based on specific cause)
– Surgical correction
– Endocrine deficiency in spayed female
• Diethylstilbestrol (PO or inj)
– Phenylpropanolamine (for loss of sphincter tone)
• Client info
– Doses will have to be adjusted for individual animals
– Paralytic bladder incontinence may require manual
expression or catheterization several times a day