Lecture 16

Question 1

What are the general characteristics of feline lower urinary tract disease (FeLUTD)?

Answer 1

-cats exhibiting clinical signs of lower urinary tract dz
-common; occurs in about 5% of feline patients
-FIC accounts for 55-75% of cases
-two groups are cats with urethral obstruction and non-obstructed cats with clinical signs

Question 2

What are the possible etiologies of FeLUTD?

Answer 2

-idiopathic (most common)
-feline idiopathic cystitis
-urethral plugs
-uroliths
-UTI (very uncommon)
-neoplasia (very uncommon)

Question 3

What is the pathophysiology behind feline idiopathic cystitis?

Answer 3

-clinical signs occur due to increased sympathetic activity/outflow from the brainstem secondary to stress or anxiety
-normal cats under stress have an initial catecholamine release followed by acclimation and return to baseline
-cats with FIC have an exaggerated and/or extended catecholamine response

Question 4

Which site in the brain is the most important source of norepinephrine in the feline CNS?

Answer 4

locus coeruleus

Question 5

How does stress affect the locus coeruleus?

Answer 5

-stress stimulates activity in the LC, increasing sympathetic output to the periphery
-chronic activation of this pathway leads to increased norepinephrine in the CSF, nervous tissue, plasma, bladder, and urine in FIC cats

Question 6

Why is it important that increased sympathetic nervous system activity promotes release of inflammatory mediators throughout the body?

Answer 6

-alteration of urothelial permeability ->
-noxious components of urine gain access to bladder wall ->
-initiates neurogenic inflammation

Question 7

What is a urethral plug?

Answer 7

mix of proteinaceous matrix and struvite crystals

Question 8

What is the pathophysiology of urethral plugs?

Answer 8

-pain stimulates further release of catecholamines
-increased urothelium permeability
-leakage of serum contents into urine
-increased protein presence for matrix formation and increased urine pH
-formation of massive numbers of struvite crystals

Question 9

What are the characteristics of the urinary tract glycosaminoglycan layer?

Answer 9

-protects bladder wall from noxious substances in urine
-defects result in pain/inflammation of bladder wall
-defects seen in cats with FIC

Question 10

What ultimately leads to urethral plug formation?

Answer 10

protein matrix forms a web-like structure in the urethra that traps struvite crystals

Question 11

Why are UTIs rare in young, healthy cats?

Answer 11

increased urine osmolality combined with other host defense mechanisms

Question 12

What is the clinical presentation of obstructive FeLUTD?

Answer 12

-male cats between 1 and 8 years old
-unproductive straining to urinate
-hiding
-vocalization
-licking of genital region
-presentation similar to constipation
-fractious/resist examination early on
-depression later on
-enlarged, firm bladder

Question 13

What is the clinical presentation of non-obstructive FeLUTD?

Answer 13

-variable clinical signs; often stranguria, pollakiuria, hematuria, dysuria
-vocalization during urination
-periuria/urination in inappropriate places
-subtle signs of stress/overgrooming
-small bladder with thickened wall
-cystocentesis attempts possibly unrewarding

Question 14

What are the differential diagnoses for cats presenting with lower urinary tract signs?

Answer 14

-behavioral inappropriate urination
-FIC
-uroliths
-UTI
-neoplasia
-anatomic defects

Question 15

How is the etiology of FeLUTD diagnosed?

Answer 15

-diagnostic imaging to ID uroliths, anatomic defects, or neoplasia
-ultrasound combined with radiographs

Question 16

How is an obstructive FeLUTD identified?

Answer 16

-palpation of enlarged, firm bladder
-urinalysis collected via cystocentesis or catheter
-CBC/chem; assessing creatinine, BUN, potassium
-ECG to assess cardiotoxicity associated with hyperK

Question 17

How is a non-obstructive FeLUTD identified?

Answer 17

-diagnostic imaging
-CBC/chem/UA
-cystoscopy to exclude alternative diagnoses

Question 18

What are the characteristics of crystalluria?

Answer 18

-unlikely the cause of FeLUTD
-most likely due to inflammation
-associated with obstruction in males
-not considered a therapeutic target

Question 19

What are the management steps for obstructive FeLUTD?

Answer 19

*recognize obstructed patient
-male
-enlarged, firm bladder

*blood work and ECG to identify stability
-check for azotemia, hyperK, acidosis, bradycardia, arrhythmia

*placement of IV catheter and patient sedation

*unblock with catheter placement

Question 20

Which drugs are used for the treatment of hyperkalemia?

Answer 20

-calcium gluconate
-albuterol sulfate
-regular insulin + dextrose
-sodium bicarbonate

Question 21

What are the characteristics of post-obstructive diuresis?

Answer 21

-monitor urine output for 24 to 48 hours post-blockage
-recommended to measure urine output every 2 to 4 hours and match ins with outs
-cause is unknown
-self-limiting; usually resolves in 24 to 48 hours
-wait to remove catheter until post-obstructive diuresis resolves and urine is clear of macroscopic blood

Question 22

What is the multimodal approach to treating FeLUTD?

Answer 22

-environmental enrichment
-diet/feeding management
-pheromones
-pharmacology

Question 23

What are the characteristics of environmental modification as a treatment step for FeLUTD?

Answer 23

-clinical manifestation of FIC is due to inappropriate response to stress
-want to identify and eliminate possible stressors
-surveys have been developed to help owners and practitioners identify stressors

Question 24

What is the # of cats plus 1 rule?

Answer 24

there should be # of cats + 1 amount of all shared resources; litter boxes, food bowls, water bowls, scratching posts, etc.

Question 25

How can the environment be modified to help treat FeLUTD?

Answer 25

-keep litter boxes clean and away from other pets -keep water bowls clean, filled, and away from kids/other pets -use wide water bowls -provide elevated places -use toys that encourage interaction between owner and pet -mitigate conflict between pets -have owners observe cats for signs or stress or conflict

Question 26

How does diet/feeding play into FeLUTD treatment?

Answer 26

-role not entirely clear -diets are often acidified and magnesium-restricted -feeding of canned, moist diet lowers incidences and recurrence of FIC -ingestion of wet food lowers urine osmolality and conc. of noxious substances -feeding of wet food encourages interaction between owner and pet

Question 27

What are the key aspects of changing a cat's diet when aiming for urinary support?

Answer 27

-avoid abrupt switches; can trigger further cystitis episodes -offer new wet food alongside previous food at first -do not force switch if pet chooses not to switch to wet food naturally

Question 28

How can eating environment play a role in FeLUTD treatment?

Answer 28

-most cats prefer to eat alone without distraction -more social cats may prefer company during meals -choose the best dining experience that minimizes stress for cat

Question 29

What are the characteristics of pheromones?

Answer 29

-chemical messengers conveying information between members of same species -cats release pheromones from facial scent glands -synthetic analogs available for purchase -studies are lacking; may decrease unwanted behaviors and increase grooming/eating in hospitalized patients

Question 30

What are the characteristics of amitriptyline?

Answer 30

-tricyclic antidepressant that causes urethral relaxation -some studies show no benefit; others show significant benefit -can be compounded into a liquid for ease of dosing

Question 31

What are the characteristics of prazosin?

Answer 31

-alpha-blocker that may decrease urethral spasms -no controlled studies to support or discourage use

Question 32

Which analgesics are used in the management of FIC?

Answer 32

-buprenorphine -butorphanol -robenacoxib -gabapentin

Question 33

What is the benefit of single low-dose fraction radiation therapy to the urinary tract?

Answer 33

may reduce severity and frequency of clinical signs associated with FIC in cats

Question 34

What are the characteristics of surgery as an FeLUTD treatment?

Answer 34

-perineal urethrostomy done when signs cannot be controlled -considered after other alternative treatments are exhausted -risk of incontinence -high lifelong risk of infection -requires anatomic modification

Question 35

What is the prognosis for FeLUTD?

Answer 35

-most cats respond to multimodal therapy approach -cats that do not respond require perineal urethrostomy -surgery does not address the underlying issue that lead to clinical signs