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Sclerotherapy for renal hematuria

Idiopathic renal hematuria (IRH), or benign essential renal hematuria, is a rare condition of chronic severe bleeding coming from the kidney. This condition typically results in bloody urine that is not associated with trauma, stone disease, neoplasia, or other obvious causes. IRH is typically seen in otherwise healthy large-breed dogs and has also been seen in cats. Affected dogs have been described as being young, ranging in age from 2 months to 11 years, and are most commonly < 2 years of age. Left-sided lesions appear to be more common (approximately 75% reported) however, the condition has been reported to occur bilaterally as well which may be present at the time of the diagnosis but may also not be present and develop in the other kidney later in the future. About 20% of dogs will have the condition on both kidneys. In humans, the causes for the kidney bleeding include hemangiomas and papillary angiomas (benign vessel abnormalities) found inside the kidney pelvis. This is also believed to be the case in animals. If left untreated, the animal will develop anemia, iron deficiency, and it may also develop blood stones or clots that may cause blockage of the kidney and/or urethra or difficulty urinating. Cystoscopy for evaluation of the ureteral openings is the method of choice for a definitive diagnostic.

Cystoscopic evaluation of dog with renal hematuria (blood coming from kidney).

Options for the treatment of IRH include kidney removal (no longer recommended), topical sclerotherapy (infusing silver nitrate and/or povidone iodine into the kidney pelvis to cauterize and bleeding vessel), ureteroscopic electrocautery, partial occlusion of the kidney artery, and medical supplementation with a Chinese herb called Yunnan Baiyao or aminocaproic acid. Because topical sclerotherapy is safe, effective, minimally invasive and kidney sparing, it should be considered prior to other techniques.

Catherization of ureter via endoscopy and fluoroscopy to perform sclerotherapy for renal hematuria.

In female dogs, sclerotherapy can be performed in full through endoscopy through the urethra. However, in male dogs, a small surgical approach to the perineal area is needed to allow better visualization and introduction of catheters in the ureteral openings. [PetName] will have a small incision below the anal sphincter that will heal on its own. No special care will be needed unless you notice blood, discharge, swelling or urine coming from the area. No sutures are needed or present in the area. After sclerotherapy, a ureteral must be placed and left in place for 2-4 weeks to prevent the risk of swelling and blockage of the kidney and severe inflammation of the kidney and ureter. General but brief anesthesia will be needed to remove the stent which can be removed via regular cystoscopy (via [PetHisHerLowercase] urethra) unless it has migrated into the ureter or kidney. In that case, a perineal approach or cystotomy would be needed again. 

Fluoroscopic evaluation of renal pelvis prior to sclerotherapy in a dog with renal hematuria.

Complications of this procedure include pollakiuria (increased frequency of urination due to perceived discomfort secondary to the ureteral stent), ureteral stent migration into the proximal portion of the urethra or into the bladder, kidney pain, perforation of the ureter or kidney pelvis, infection of the kidney or the surgical incision in case of males and not appropriate healing of the perineal incision with subsequent leakage of urine through the incision. Fortunately, all of these complications are extremely rare.


In average, about 80% of animal that go through this treatment, will have bloody urine completely resolved. The other 20% usually have significant improvement. For the animals with minimal or no improvement, ureteroscopic electrocautery would be the next step. Some medications can also be attempted if the bleeding is only minimal. Bloody urine may take up to 7 days to completely resolve but may resolve immediately after the procedure. 

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