Page 968 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Urinary system 943

VetBooks.ir on the location of the ectopic ureter, the severity of from a catheterised sample. It is important to look
for concurrent uroliths in the bladder and kidneys,
clinical signs and the intended use of the animal,
surgical correction may be required. Surgical relo-
cation of the ectopic ureter into the bladder may be as multifocal urolithiasis is not uncommon.
possible; otherwise, nephrectomy can be performed Differential diagnosis
in patients with unilateral disease. Differential diagnoses include calculi in other parts
of the urinary tract, bladder paralysis, urinary tract
URETEROLITHIASIS trauma, renal failure, sabulous urolithiasis and
neoplasia.
Definition/overview
Ureterolithiasis, the presence of calculi in one or Management
both ureters, is a rare problem in the horse. Ureterolithiasis can be treated surgically with the
calculus removed via a ureteral incision. In mares
Aetiology/pathophysiology a Dormia basket is placed manually into the ure-
Ureteroliths may arise as a sequela to degenerative or ter to ensnare and remove the calculus. This tech-
inflammatory processes in the kidney. Inflammatory nique may be employed in cases where the calculi
debris can serve as a nidus for calculus formation are ≤2 cm. Lithotripsy, where calculi are fragmented
(see Fig. 7.23) within the ureter or nephroliths may through the delivery of an electrical impulse/shock
move into the ureters and cause obstruction. wave, could also be attempted, but is of limited avail-
ability. Unilateral nephrectomy may be the only
Clinical presentation possible management of ureterolithiasis in some
With unilateral disease, a low-grade intermittent colic cases. Prior to nephrectomy, it is essential that
may be the only clinical sign present. Clinical signs in concurrent disease in the contralateral ureter and
advanced cases are consistent with CKD, which may kidney are ruled out. Antimicrobial therapy and i/v
develop secondarily to ureteral obstruction. fluid therapy should support the above procedures as
has been previously discussed. Treatment of CKD is
Diagnosis discussed elsewhere (p. 936).
Haematology is unremarkable until renal failure has
developed (see previous discussion, p. 931). On uri- Prognosis
nalysis, intermittent or persistent pigmenturia and Bilateral ureterolithiasis that advances to CKD
increased numbers of erythrocytes are usually pres- carries a grave prognosis. Unilateral disease has a
ent. The SG can be variable depending on whether better prognosis, especially if calculi can be suc-
intrinsic renal failure has developed, and the dis- cessfully removed. It is believed that initiating renal
ease is unilateral or bilateral. If bilateral obstructive disease predisposes horses to develop ureteroliths.
disease is present, urine may not be obtained. The Avoiding the administration of nephrotoxic agents,
ureterolith or enlarged ureters may be palpable p/r. provision of a good diet and ensuring adequate
Distended ureters may be evident ultrasonographi- water consumption increase the chance for good
cally. Urine culture should be performed, preferably recovery.

DISEASES OF THE URINARY BLADDER

BACTERIAL CYSTITIS blood, inflammatory cells and bacteria in the urine.
It is rarely a primary disease.
Definition/overview
Bacterial cystitis is an inflammation of the bladder Aetiology/pathophysiology
caused by bacterial infection and is characterised by Cystitis is most often a secondary disease that can
dysuria, stranguria, pollakiuria and the presence of develop from urine stasis (bladder paralysis), urinary