(T3) Lecture 12a - Nutritional disorders and wellness diets 2 Flashcards
What is Feline Lower Urinary Tract Disease (FLUTD) linked to?
Urinary pH!
- pH is either too low or too high; both result in unique crystal formation
- not a single disease, but a syndrome = collection of clinical signs that are non-specific
Clinical signs of FLUTD
- Non-specific; depend on location, size and number of crystals or uroliths
- In some cases: partial or total urethral obstruction (very painful and a medical emergency)
Initial signs:
- frequent urination
- urination at inappropriate places
- hematuria
- sometimes strong odor of ammonia
- painful urination by the cat
What is the veterinary treatment if obstruction occurs with FLUTD?
Medical emergency!
- Fluid replacement therapy
- Flushing out of the urolith
- Relief of bladder distension (cystocentesis)
FLUTD: Struvite vs. Calcium Oxalate Uroliths
High urinary pH: Struvite crystals form
Low urinary pH: Calcium Oxalate crystals form
Why is identification of mineral composition or uroliths important?
Dietary management is directed toward eliminating specific type of urolith or crystalline plug
Nowadays, higher incidence of calcium oxalate FLUTD than struvite FLUTD due to increased use of urine-acidifying diets
What are the conditions for STRUVITE crystal formation?
- High concentration of composite minerals:
- Mg
- P
- Ammonium - Sufficient time in urinary tract to allow crystallization
- Urine pH > 7.0
- Small volumes of concentrated urine
- No relation to urinary tract infections
- usually secondary infections, but not the underlying cause of FLUTD
What are the conditions for calcium oxalate crystal formation?
- Calcium oxalate soluble in alkaline pH
- precipitate in acidified urine - Some cats have mild acidemia
- induced by consumption of acidified diet
- metabolic effect: production of acidified urine, increased serum calcium and urinary calcium excretion
- formation of calcium oxalate crystals
Apart from mineral analysis, what instrument might be handy for diagnosis of calcium oxalate vs struvite crystals?
microscope
Long term dietary management of FLUTD
- Removal or dissolution of urinary crystals
- Prevention of urolith formation; depend on type of urolith
FLUTD - Dietary Management
Struvite Uroliths
- dietary dissolution can take months
- monitor (palpation, radiography)
- feed special diet for 1 month following complete dissolution then switch to maintenance diet to prevent
Maintenance diets for prevention of struvites:
- should produce slightly acidified urine
- moderate in caloric density
- high in digestibility
Dietary ingredients that increase urinary acid excretion
- proteins of animal origin, corn gluten meal, methionine, phosphoric acid
- avoid large amount of cereal grains
For cats not drinking enough water: canned food
- increased urinary volume and lower urine specific gravity (high gravity = concentrated urine)
What nutrients are used for struvite urolith dissolution and prevention? What nutrients are used for calcium oxalate prevention?
Phosphorus, sodium, magnesium
Calcium, phosphorus, sodium, magnesium
Can calcium oxalate uroliths be dissolved?
No. Must be removed by surgical intervention or urohydropropulsion
Dogs and cats with kidney disease have progressive loss of what?
Functioning nephrons
- however, kidney has large capacity to compensate
- clinical signs with 70-85% loss of fxning nephrons
- healthy kidneys have tremendous extra capacity
Potential underlying causes of chronic kidney disease
- Trauma
- Infection
- Immunological disease
- Tumors
- Ischemia
- Exposure to toxins
- Older age
*In most cases underlying cause no longer present = difficult to identify when cat or dog develops renal failure
Why does increased water intake occur with chronic kidney disease?
Filtration capacity of kidneys decrease so needs more water to filter out the “bad”