Transcript Diseases of Urinary System

ADVERSITY
“No pressure, no diamonds.”
-Mary Case
DISEASES OF THE URINARY SYSTEM
Cystitis
Cystic calculi
Urinary obstruction
ARF & CRF
Incontinence
BLOOD FLOW THROUGH THE KIDNEYS
 Renal arteriole > glomerulus > bowman’s capsule >
proximal convoluted tubule > loop of Henle >
ELIMINATED: distal convoluted tubule > collecting ducts
> renal pelvis > urine
COMPONENTS OF THE URINARY SYSTEM
and ITS FUNCTIONS
 Functions of the kidneys
 Excretion:
 produce urine
 Maintain homeostasis
 Blood filtration, reabsorption, secretion
 Fluid balance regulation
 Acid-base balance regulation
 Hormone production
DISEASES OF THE URINARY SYSTEM
 URINARY SYSTEM IS NORMALLY STERILE
AND RESISTANT TO BACTERIAL
INFECTION
 Voiding of urine
 Urethral/ureteral peristalsis
 Glycosaminoglycans in the surface mucosal
layer
 pH
RECOGNIZING URINARY SYSTEM
DISORDERS
About 4 million cats a year are destroyed for
“elimination problems”.
DIAGNOSING URINARY SYSTEM
DISORDERS
 DIAGNOSTIC TESTS THAT MAY BE DONE IN PATIENTS
WITH URINARY DISEASE
 URINALYSIS (dipstick and sediment exam)
 RADIOGRAPHS
DISEASES OF THE URINARY SYSTEM
Cystitis
Cystic calculi
Urinary obstruction
ARF & CRF
Incontinence
Feline Idiopathic (Interstitial) Cystitis
aka FUS/ FLUTD
FACTS:
-Occurs in cats 2-6 yrs old
-Occurrence in males > females
-cause unknown, multi-factorial
-not caused by bacterial infection
-recurrence is likely
Feline Idiopathic (Interstitial) Cystitis
 Clinical Signs
 pollakiuria
 Hematuria
 Dysuria
 Periuria (sinks, tubs, carpet, etc.)
Feline Idiopathic (Interstitial) Cystitis
 Diagnostics
 Urinalysis/culture to r/o bacteria as cause
 Only 1%-3% of all feline cystitis is caused by
bacteria
 Radiographs to r/o calculi;
 contrast studies may show thickened bladder wall
Feline Idiopathic (Interstitial) Cystitis
 Treatment
 Avoid unnecessary antibiotics
 Change diet from dry to moist
 Or salt food to ↑ water intake
 Reduce stress from other cats, kids, etc
 Provide hiding places
 Pheromonotherapy
 Behavior modification drugs (may also have pain reducing
effects
 Amitryptilline (tri-cyclic antidepressant)
 Clomipramine
 Glycosaminoglycan replacement
 Cosequin for cats
 Adequan
Feline Idiopathic (Interstitial) Cystitis
 Client info
 Disease is self-limiting
 As many as 85% of cats will have resolution of
clinical signs in 7-10 days
 May be recurring problem
 No definitive cure
 Reduce stress
Canine Bacterial Cystitis
 Cause: Ascending bacteria
up the urethra
 Signs
 ↑ frequency of urination
 Hematuria
 Dysuria
 Cloudy urine, abnormal
color
 Frequent licking of
vaginal/urethral area
Canine Bacterial Cystitis
 Diagnostics
 Urinalysis:
 ↑WBC’s, bacteria
 Common bacteria:
E.coli, Proteus spp.
 Urine
culture/sensitivity
 Collect by
cystocentesis or midstream collection
Canine Bacterial Cystitis
 Treatment
 Antibiotics according to sensitivity
 Treat acute infections x 10-14 d
 Subsequent infections x 4-6 w
 Avoid trauma to urinary tract during surgery
 Patients needing indwelling catheters should
have a closed system
Closed Urinary Catheter System
Canine Bacterial Cystitis
 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
DISEASES OF THE URINARY SYSTEM
Cystitis
Cystic calculi
Urinary obstruction
ARF & CRF
Incontinence
Feline Uroliths and Urethral Plugs
“Plugged” or “Blocked” male
cats are commonly seen in
small animal practice and can
be fatal if not relieved
Feline Uroliths & Urethral Plugs
 The two most common causes of urethral
blockage are uroliths and urethral plugs
 UROLITHS: composed of minerals and a
small amount of matrix
 URETHRAL PLUGS: composed of small
amount of minerals and large amount of
matrix
Feline Uroliths and Urethral Plugs
• Signs
– Hematuria
– Dysuria
– Periuria
– Anorexia, vomiting
– Collapse, death
• Non-specific signs:
– Hiding
– Crying while urinating
– Frequent trips to the
litterbox
Feline Uroliths and Urethral Plugs
 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
(cystine) and require double
contrast
Pneumocystogram
Feline Uroliths and Urethral Plugs
 Uroliths damage bladder, making it more
susceptible to bacterial infection, hematuria
 Uroliths can cause blockage of the urethra
of males
 Bladder will fill with urine
 Kidneys will stop working
 Blood/body will become toxic (azotemic)
Feline Uroliths and Urethral plugs
Feline Uroliths and Urethral Plugs
• Dx
 Palpation of bladder
• Obstructed bladders are full and tight
 Radiographs may show uroliths on routine films
 Ultrasonography can locate position of urolith
 Urolith analysis is necessary to determine its constituents
 EKG: atrial standstill, bradycardia, hyperkalemia
Feline Uroliths and Urethral Plugs
Normal double-contrast cystogram
Double-contrast cystogram
with stones
pneumocystogram
Ultrasound of bladder stone
Feline Uroliths and Urethral Plugs
 Treatment
 Medical treatment (chronic, non-obstructed)
 Dissolve struvite uroliths (most common- ~60%) by
acidifying urine and feeding diet low in Mg (Hill’s S/D,
c/d, others)


Should resolve in 4-8 wk
Re-radiograph, and continue diet 1 mo after uroliths gone
 Cystotomy to remove stones
 Antibiotics according to culture/sensitivity
Feline Uroliths and Urethral Plugs
Feline Uroliths and Urethral Plugs
 Medical treatment (obstructed)
 This is a medical emergency
 Anesthetize (short acting)
 *USE LESS ANESTHESIA IN AZOTEMIC CATS*
 Pass Tom cat catheter and back flush
 Sew catheter in place for 1-3 d, using a closed system
Feline Uroliths and Urethral Plugs
Closed Urinary Catheter System
Feline Uroliths and Urethral Plugs
 Surgical treatment (chronic obstructers)
 Perineal urethrostomy (PU)
 New opening for urethra is created proximal to
narrowing
 Urethral opening looks similar to female
anatomy
*Goal of surgery is to decrease the likelihood of
life-threatening obstruction*
Feline Uroliths and Urethral Plugs:
Perineal Urethrostomy
Feline Uroliths and Urethral Plugs:
Perineal Urethrostomy
Canine Urolithiasis
Os Penis
Canine Urolithiasis
 Uroliths damage mucosa of urinary tract making it
susceptible to infection
 Uroliths can obstruct urine flow in males
 Clinical Signs
 pollakiuria
 Dysuria
 Hematuria
Canine Urolithiasis
 Dx
 Urinalysis
 Crystalluria
 Hematuria
 ↑ bacteria
 Radiographs
Canine Urolithiasis
Canine Uroliths
Urolith
Breed
Sex
Contributing factors
Struvite
min sch
cats
female (80%)
alkaline urine
(Mg Ammonium Phos)
bacteria→urease→↑pH
minerals (diet)
Rx
acidify urine
antibiotics
Only Hill’s s/d (dissolve)
↓protein (ammonia)
↑H2O intake (flush stones)
acidy urine
Calcium Oxalate
(30-50% of
all stones)
Urates
cats
min sch
Lhasa, Yorkie
min poodle
Shih Tzu
Dalmatians
E bulldogs
min schnauzer
Shih Tzu
Yorkshire terrier
males
males
diet high in protein
hypercalcemia
Cushing’s Dis
use of cortisone
acid urine
↑ uric acid from kidneys
acid urine
Sx removal (only Rx)
↓ dietary Ca
Hill’s u/d, w/d, k/d
Allopurinol
(gout in humans)
+
K Citrate (↑ urine pH)
Hill’s u/d,
Canine Uroliths
Struvite
Calcium Oxalate
Type of stone cannot be determined by appearance; chemical analysis is required
Urate
Urolithiasis (Canine)
• Treatment
 Medical (dissolve stones if Struvite)
• diet
• Acidify urine
– Urinary acidifiers (methionine, Methogel)
• ↑ urine output
– Add salt to diet, increase water intake
 Antibiotics for bacterial infection
 Surgical removal ( Ca Oxalate)
• Some uroliths are not amenable to Medical Rx
• However, the cause of uroliths must be dealt with medically (prevention)
• STONE ANALYSIS ISVITAL FOR APPROPRIATE TREATMENT
Canine Urolithiasis: Cystotomy for stone
removal
Canine Urolithiasis
What do you see?
Canine Urolithiasis
 Client info
 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
EDUCATION
“It is possible to store the mind with a
million facts and still be entirely
uneducated.”
- Alec Bourne
DISEASES OF THE URINARY SYSTEM
Cystitis
Cystic calculi
Urinary obstruction
ARF & CRF
Incontinence
Renal Failure
 ~20% of Cardiac output
 Filtered by renal corpuscle
 Reabsorbed by kidney tubules
 Waste excreted as urine
 Renal Failure due to:
 ↓ blood flow (hypoperfusion)
 Damage to nephron and
glomerular filtration declines
resulting in azotemia
AZOTEMIA
Pre-renal
dehydration
Renal
Primary kidney disorders
Post-renal
Urinary tract obstruction
Acute Renal Failure
 Three distinct phases:
 Induction: the time from the initial insult until decreased renal
function is apparent (hours to days)
 Maintenance: the time period during which renal tubular
damage occurs (weeks to months)
 Recovery: the time during which renal function improves,
existing nephrons hypertrophy and compensate for those
damaged, and tubular repair occurs (when possible)
Stages of Kidney disease
Loss of Renal Reserve - Early signs of PU/PD
PU= polyuria (increased urination)
PD= polydipsia (increased drinking)
Renal Insufficiency - Early warning signs,
such as increased thirst, may begin to
appear
Renal Failure (Azotemia) - Kidneys cannot
eliminate waste efficiently, causing signs of
illness
Advanced Kidney Failure (Uremia) - Severe
signs of illness appear; eventually, collapse and
death result
Acute Renal Failure
 An abrupt decrease in glomerular filtration →azotemia
 Causes
 Damage to nephron
 Nephrotoxic drugs






Aminoglycosides (gentamicin, streptomycin)
Chemotherapeutic agents
Antifungal medications
Analgesics (acetaminophen)
Anesthetics (methoxyflurane [Metafane])
Ethylene glycol (antifreeze)
Acute Renal Failure
 Causes:
 Infections (pyelonephritis)
 Immune-mediated diseases
(Glomerulonephritis)
 Metabolic: Hypercalcemia
 ↓ 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
Acute Renal Failure
 Dx
 Urinalysis
 urine sediment - casts
 low sp gravity (unable to concentrate urine)
 CBC
 dehydration (↑PCV)
 acidosis
 Chem panel
 ↑ BUN, Creatinine
 ↑K+, Phosphorus
Acute Renal Failure
 Tx (aim is to restore renal
hemodynamics)
 Relieve tubular obstruction
 Discontinue any toxic drugs
 IV fluids
 Correct dehydration
 Correct acid/base imbalance
Acute Renal Failure
 Client info
 Renal function may never be like it was before
injury
 Prognosis is guarded especially with older pets
 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)
Dogs > 8 yrs
Cats > 10 yrs
Chronic Renal Failure
 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
• protein matrix (Tamm-Horsfall
mucoprotein)
that makes up the hyaline cast (hyaline
with fat)
• particulate material from degenerating
cells
• is present within the cast matrix
(hyaline to finely granular cast).
Chronic Renal Failure
 Dx
 Acidosis
 Anemia
 ↑ BUN, Creatinine
 increased phosphorus
 Hypokalemia
Proteinuria
Chronic Renal Failure
 Tx
 Fluids for dehydration (IV, SQ)
 Potassium gluconate, calcium carbonate for
electrolyte imbalances
 Phosphorous binders: Aluminum hydroxide
 Sodium bicarbonate for pH adjustment
 Hormones
 Epoetin
 Vit B supplements
Chronic Renal Failure
 Client info
 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
ARF
(large size)
Inc.
CRF
(small size)
Dec.
Azotemia: Bun
and Creatine
Phosphorous
Inc.
Inc.
Inc.
Inc.
Potassium
Inc.
Dec.
PCV
Other
Acidosis,
proteinuria
DISEASES OF THE URINARY SYSTEM
Cystitis
Cystic calculi
Urinary obstruction
ARF & CRF
Incontinence
Urinary Incontinence
Loss of voluntary control of micturition
 Causes
 Neurogenic—loss of normal neural function causing a paralyzed
bladder
 Ectopic ureters
 Patent urachus
 Endocrine imbalance (after spay)
Urinary Incontinence
 Signs
 Urine leakage when pet is sleeping or exercising
 Perianal area of pet is always 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 (PROIN: 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
References
 Alleice Summers, Common Diseases of Companion Animals
 http://veterinarymedicine.dvm360.com/vetmed/article/article
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Detail.jsp?id=738082
http://ahdc.vet.cornell.edu/clinpath/modules/index.htm
http://www.vetmed.wsu.edu/ClientED/anatomy/dog_ug.aspx
http://veterinarynews.dvm360.com/dvm/article/articleDetail.j
sp?id=533210
http://www.walthamusa.com/articles/c-kidney.pdf