Urinary Diseases

    CONGENITAL AND INHERITED ANOMALIES   

      1.     Renal anomalies

  1. A.     Renal dysplasia & hypoplasia

These defects are most common in dogs and have been reported in many breeds. Renal dysplasia may be unilateral or bilateral. For more information click here or call your veterinarian.

  1. B.      Renal agenesis

Renal agenesis is always accompanied by ureteral aplasia and may be associated with aplastic reproductive tissues on the same side. For more information click here or call your veterinarian.

  1. C.     Polycystic kidneys

Multiple cysts form within the renal parenchyma, and such kidneys are usually grossly enlarged on palpation. For more information click here or call your veterinarian.

  1. D.     Simple renal cysts

These solitary, unilocular cysts generally do not communicate with the renal collecting system; the rest of the kidney is normal. For more information click here or call your veterinarian.

  1. E.      Perirenal pseudocysts

Perirenal pseudocysts are accumulations of fluid that develop external to the renal parenchyma; they have been identified in cats. For more information click here or call your veterinarian.

  1. F.      Miscellaneous

Double or multiple renal arteries are seen in ~5% of dogs. Other congenital defects include renal malpositioning, renal fusion, and nephroblastoma. For more information click here or call your veterinarian.

      2.     Ureteral anomalies

  1. A.     Ectopic ureter

This defect is most commonly reported in 3- to 6-mo-old dogs, with females affected 8 times more frequently than males. Continual dripping of urine is the classic sign. For more information click here or call your veterinarian.

  1. B.      Miscellaneous ureteral anomalies

Less frequently recognized ureteral anomalies include aplasia, duplication, and ureterocele. For more information click here or call your veterinarian.

      3.     Bladder anomalies

  1. A.     Urachal remnants

Congenital anomalies resulting from incomplete urachal closure include patent urachus, urachal diverticulum, umbilical urachal sinus, and intra-abdominal urachal cyst. For more information click here or call your veterinarian.

  1. B.      Miscellanous bladder anomalies

Bladder duplication, dysplasia, hypoplasia, agenesis, and exstrophy have been reported and are often associated with other urinary tract defects. For more information click here or call your veterinarian.

      4.     Urethral anomalie

  1. A.     Hypospadias

This developmental defect results from failure of the urethral grooves to fuse during phallus elongation. For more information click here or call your veterinarian.

  1. B.      Urethrorectal fistulas

These appear to be more prevalent in English Bulldogs, possibly as a congenital defect due to abnormal separation of the embryonal cloaca into the urethra and rectum. For more information click here or call your veterinarian.

II.       INFECTIOUS DISEASES OF THE URINARY SYSTEM

1.     Bacterial cystitis

Bacterial cystitis is infection and inflammation of the urinary bladder. Clinical signs are pollakiuria, hematuria, dysuria, and urinating in inappropriate places. For more information click here or call your veterinarian.

    2.     Pyelonephritis

Kidney infection (pyelonephritis) is usually due to ascending bacteria, although hematogenous spread is possible. For more information click here or call your veterinarian.

    3.     Intersititial nephritis

Acute interstitial nephritis in dogs is caused most often by Leptospira interrogans ( Leptospirosis in Dogs). Cats can develop leptospirosis, although signs are less severe than in dogs.

    4.     Capillaria plica infection

Capillaria plica may infect the urinary bladder, and occasionally the ureters and renal pelvises, of dogs and cats. For more information click here or call your veterinarian.

    5.     Giant kidney worm infection

Dogs and humans can be infected. The larvae penetrate the bowel wall and migrate first to the liver and later to the kidneys. For more information click here or call your veterinarian.

III.       NONINFECTIOUS DISEASES OF THE URINARY SYSTEM

    1.     Renal dysfunction

    1. A.     Chronic Kidney Disease 

This disease process involves a loss of functional renal tissue due to a prolonged (3 mo), usually progressive process. Dramatic changes in renal structure may be seen, although structural and functional changes in the kidney are only loosely correlated. For more information click here or call your veterinarian.

    1. B.      Acute Kidney Disease 

Acute kidney disease is seen when a sudden, major insult damages the kidneys. The principal causes are toxins (eg, ethylene glycol, aminoglycoside antibiotics, hypercalcemia, hemoglobinuria) and ischemia (eg, embolic showers from disseminated intravascular coagulation or severe prolonged hypoperfusion). For more information click here or call your veterinarian.

    2.     Glomerular Disease 

Glomerular disease is a well-recognized cause of chronic (but not acute) kidney disease in dogs, and is also occasionally observed in cats. For more information click here or call your veterinarian.

    3.     Renal Tubular Defects

  1. A.     Renal Tubular Acidosis 

The form of metabolic acidosis that occurs in Stages II-IV of acute and chronic kidney disease, referred to as uremic acidosis, is due to reduced urine-acidifying ability of diseased kidneys. For more information click here or call your veterinarian.

  1. B.      Fanconi Syndrome 

Fanconi syndrome is a generalized proximal tubular reabsorptive defect resulting in excessive loss of many solutes in the urine. For more information click here or call your veterinarian.

  1. C.     Renal Glucosuria 

This is usually a congenital defect in proximal tubular handling of glucose that results in glucosuria despite normal blood glucose concentration. For more information click here or call your veterinarian.

    4.     Obstructive Uropathy

Even though the kidneys would otherwise be able to function normally, obstruction of urine flow at any point below the level of the kidneys leads to accumulation of metabolic wastes and postrenal azotemia/uremia. Obstruction of the urethra by uroliths in dogs and by matrix-crystalline plugs in cats are the most common causes, although uroliths, tumors, or blood clots may obstruct the ureters (or urethra) in either species. For more information click here or call your veterinarian.

IV.       Neoplasia 

    1.     Neoplasms of the Kidney 

Neoplasms of the kidney are uncommon. Benign neoplasms are uncommon, usually incidental findings at necropsy, and generally of little clinical significance. Primary malignant renal neoplasms (except nephroblastomas) are most common in middle-aged to older animals. For more information click here or call your veterinarian.

    2.     Neoplasms of the Lower Urinary Tract 

Neoplasms of the ureters, bladder, and urethra are uncommon in dogs and rare in cats. The mean age of affected dogs and cats is 9 yr. For more information click here or call your veterinarian.

V.       Disorders of Micturition 

Disorders of micturition result from a dysfunction in the storage or voiding of urine and may be neurogenic or non-neurogenic in origin. Urinary incontinence is the failure of voluntarily control micturition, with constant or intermittent unconscious passage of urine. For more information click here or call your veterinarian.

VI.       Urolithiasis

    1.     Canine Urolithiasis 

    1. A.     Struvite Stones

The most common urinary stones in dogs are composed of struvite. In most cases, struvite uroliths form in association with urinary tract infections with bacteria. Unlike in cats, in which they are frequent, sterile struvite uroliths rarely form in dogs. The key to prevention of recurrence in animals with a struvite stone associated with infection is achieving and maintaining sterile urine. Routine testing of urine pH by the owner is important. If fresh urine is alkaline, a urinalysis and culture should be done, and the dog treated appropriately if an infection is present. For more information click here or call your veterinarian.

    1. B.      Calcium Oxalate Stones

Calcium oxalate uroliths have been increasing in frequency in dogs. Most affected dogs are 2-10 yr old. Recurrence is a major problem with calcium oxalate uroliths. An “ideal” diet is considered to be low oxalate, low protein, and low sodium, and would maintain urine pH at 6.5-7.5. For more information click here or call your veterinarian.

    1. C.     Urate Stones

Ammonium urate stones are most common in Dalmatians and in dogs with congenital portosystemic vascular shunts. For more information click here or call your veterinarian.

    1. D.     Cystine Stones

Stones composed almost entirely of cystine form in dogs that have a renal tubular amino acid reabsorption defect known as cystinuria. Healthy dogs demonstrate 97% fractional reabsorption of cystine, while affected dogs excrete a much greater proportion of the filtered cystine load and may even exhibit net cystine secretion. Cystine is a relatively insoluble amino acid; therefore, in high concentration it may precipitate and form stones. For more information click here or call your veterinarian.

    1. E.      Silica Stones

Early reports indicated a predominance of silica stones in German Shepherds, but many breeds have now been implicated. Urethral obstruction in males is the most common presenting problem, but signs similar to those associated with other types of uroliths also may be noted. The mean age at occurrence is ~6 yr. For more information click here or call your veterinarian.

    2.     Feline Urolithiasis and Feline Lower Urinary Tract Disease (Feline urologic syndrome, FLUTD) 

Hematuria, pollakiuria, and stranguria are the characteristic clinical signs of FLUTD in cats. Although the specific underlying etiology of this common disease may not be identified, 2 major disease categories have been suggested based on the presence or absence of mineral precipitates. For more information click here or call your veterinarian.