30 Flashcards
What is urolithiasis?
Urolithiasis is a disease characterized by the formation of uroliths, or urinary stones.
What are the causes of urolithiasis in domestic animals?
The formation of urinary stones can be a consequence of chronic inflammation of the urinary tract.
What are uroliths composed of?
Uroliths are composed of an organic matrix and crystalline minerals of various compositions. The matrix constitutes a smaller portion of 2-10%.
How are uroliths classified based on localization?
Uroliths can be classified as nephrolith (in kidneys), ureterolith (in ureters), urocystolith (in bladder), and uretrolith (in urethra).
How are uroliths classified based on mineral composition?
Uroliths can be classified as monomineral (over 70% of one dominant mineral), complex (core and shell), or mixed (not exceeding 70% of any mineral, without core and shell).
What are the shapes of uroliths?
Uroliths can be round, oval, pyramidal, spiny, or bizarre.
What are the causes of urolith formation?
Uroliths can form due to infectious causes (struvite) or metabolic causes (cystine, urate, oxalate, silicate).
What factors predispose animals to urolithiasis?
Factors include breed predisposition, age, sex, nutrition, genetic factors, pathological morphology of kidneys, urinary tract infections, metabolic defects, and urodynamic disorders.
Which breeds are predisposed to struvite uroliths?
Breeds include Miniature Schnauzer, Bichon Frise, and Cocker Spaniel.
Which breeds are predisposed to calcium oxalate uroliths?
Breeds include Miniature Schnauzer, Lhasa Apso, Yorkshire Terrier, Toy Poodle, Shih Tzu, and Bichon Frise.
Which breeds are predisposed to urate uroliths?
Breeds include Dalmatian, English Bulldog, Miniature Schnauzer, and Yorkshire Terrier.
Which breeds are predisposed to cystine uroliths?
Breeds include English Bulldog, Dachshund, and Basset Hound.
How is urolithiasis diagnosed?
Urolithiasis must be differentiated from infections and tumors. Urine analysis and possibly ultrasound examination are required.
What does urine analysis reveal in urolithiasis?
Urine analysis checks pH, presence of bacteria, and crystals, which helps identify the composition of urinary stones.
What is struvite urolithiasis in dogs?
Struvite urolithiasis is associated with infection and is characterized by colorless crystals shaped like coffin lids or X shapes.
What bacteria are associated with struvite urolithiasis?
Bacteria such as Proteus mirabilis, Proteus vulgaris, Staphylococcus aureus, and Ureaplasma urealyticum are associated with struvite formation.
What pH level indicates struvite crystals in urine?
Struvite crystals in urine indicate a pathologically high pH (above 7.2).
What are the main factors for struvite formation?
The main factors include increased concentration of ammonium ions (high protein diet) and alkaline pH.
What dietary factors contribute to struvite urolithiasis?
Dietary factors include high protein intake leading to increased urea and alkaline urine.
What is calcium oxalate urolithiasis?
Calcium oxalate urolithiasis involves the formation of dipyramidal crystals, which can be colorless or vary in color.
What conditions lead to calcium oxalate urolithiasis?
Conditions include hypercalciuria (excess calcium) and hyperoxaluria (excess oxalate).
What are the treatment options for calcium oxalate uroliths?
Treatment includes surgical removal of uroliths, urine acidification, and dietary management.
What is cystine urolithiasis?
Cystine urolithiasis involves colorless crystals with a hexagonal shape, often forming in concentrated urine with acidic pH.
What is the etiology of cystine urolithiasis?
Cystinuria is an autosomal recessive condition leading to cystine urolith formation.
What are the characteristics of cystine crystals?
Cystine crystals have equal or nearly equal sides and can occur individually, but more often aggregate into layers.
In what conditions do cystine crystals most commonly form?
They most commonly form in concentrated urine with acidic pH.
What is cystinuria?
Cystinuria is an autosomal recessive inherited metabolic disorder (tubulopathy) caused by a defective gene leading to increased cystine excretion in urine.
Which dog breeds are commonly affected by cystinuria and cystine urolith formation?
Affected breeds include: Basenjis, Basset Hounds, Bulldogs, Shih Tzus, Yorkshire Terriers, Irish Terriers, Newfoundland Dogs, Mastiffs, and their crosses.
What happens to cysteine in the proximal tubule in cystinuria?
Cysteine is not completely reabsorbed, leading to its presence in the final urine where it converts to cystine, which is poorly soluble in water.
What is the color of cystine crystals?
Cystine crystals are yellow, brown, or greenish and usually occur in several pieces.
What is purine urolithiasis?
Purine urolithiasis refers to the presence of uroliths formed from animal proteins.
What are the two groups of patients affected by urate lithiasis in dogs?
The two groups are: Dalmatian dogs and non-Dalmatian breeds.
What is the primary cause of urate stone formation in Dalmatians?
Dalmatians have a unique metabolic defect that limits their ability to oxidize uric acid to allantoin.
How much uric acid is converted to allantoin in Dalmatians compared to other breeds?
Only 30-40% of uric acid is converted to allantoin in Dalmatians, compared to 90% in other breeds.
What is the uric acid excretion level in Dalmatians?
Dalmatians excrete 400-600 mg of uric acid in 24 hours, while similar-sized breeds excrete approximately 60 mg.
What is the role of renal tubules in uric acid handling in Dalmatians?
Dalmatian renal tubules reabsorb less uric acid than other breeds and also secrete uric acid in their distal renal tubules.
Is increased urate excretion in Dalmatians a primary cause of urate lithiasis?
Increased urate excretion is a risk factor, not the primary cause, as all Dalmatians have the metabolic defect but only some develop urolithiasis.
What other types of stones can occur in Dalmatians?
About 10% of cases may involve struvite, calcium oxalate, cystine, or other types.
What factors contribute to urate lithiasis in non-Dalmatian breeds?
Factors include hyperuricosuria, hyperammonuria, and low urine pH.
What liver dysfunctions are associated with urate lithiasis in dogs?
Liver dysfunctions can lead to increased ammonia levels, often due to portosystemic shunts or cirrhosis.
What is the metabolic origin of urate?
Urate is produced during the metabolism of purines and pyrimidines found in nucleic acids.
