Contributors: Kyle Braund, Kathy Lunn, Julien Bazelle
Species: Canine | Classification: Miscellaneous
- Dysuria is defined as painful and/or difficult urination.
- Clinical evaluation of urinary function can be accomplished by a series of diagnostic procedures.
- Physical examination and a complete history of the patient are important in the diagnosis of urinary tract disease.
- Observation of the patient during urination is very helpful.
- Signs may be due to urinary tract disease or extra-urinary structures impinging on urinary tract.
Is it likely that the patient has urinary tract disease?
- Non-productive straining.
- Signs of pain while urinating.
- Hematuria Hematuria.
- Frequent attempts to urinate.
- Passage of small amounts of urine.
Care not to confuse fecal tenesmus with urinary straining.
- Systemic signs:
- Depression, vomiting, anorexia (if obstructed).
- Constipation or straining to defecate.
- Palpation of bladder size and shape:
- Palpate urethra per rectum.
- Empty bladder may indicate poor filling, bladder irritation or reflex dyssynergia.
- Large bladder may indicate outflow obstruction.
- Palpation of prostate for evidence of enlargement Prostate gland: clinical examination.
- Palpate bladder before and after urination.
- Observe urine stream during urination.
Causes of dysuria
Inflammation or infection
- Cystitis Cystitis.
- Prostatitis Acute prostatitis.
- Vaginitis Vaginitis.
- Secondary to urolithiasis Urolithiasis.
- Toxicity (eg cyclophosphamide).
- Urinary tract neoplasia:
- Urolithiasis Urinary obstruction.
- Proliferative urethritis.
- Urethral stricture.
- Extra-urinary tract masses may impinge on urinary tract.
Urinary tract trauma
- Try to answer the following questions:
- Is there evidence of difficulty urinating?
- Is there difficulty with defecation?
- Is there ever normal urine voiding?
- Is the frequency of micturition attempts increased?
- Is there obstruction to urine outflow?
- Is total amount of urine production normal?
- Is the urine color normal?
- Is there evidence of incontinence?
- In all cases of dysuria, attempts should be made to pass a urethral catheter if the bladder is full on examination.
- In functional (neurogenic) obstruction, the catheter should pass easily and the bladder can be drained.
Exercise great caution when passing a catheter in an animal with potential urethral obstruction as force can result in urethral rupture.
- Useful to determine size and position of bladder Radiography: abdomen Radiography: cystography :
- Small supports diagnosis of inflammation and increased micturition.
- Large suggests outflow obstruction.
- Assess extra urinary tract structures for abnormalities, eg prostate.
- May reveal urolithiasis.
- Evaluate sublumbar lymph nodes.
- Evaluate pelvis and spine.
- Assess size of kidneys and ureters in case of severe and often chronic obstruction Radiology: lower urinary and genital tracts.
- Needed to detect radiolucent uroliths.
- Retrograde urethrogram Radiography: urethrography to check for signs of urethral disease.
- Double contrast cystogram Radiography: double contrast cystography for bladder disease.
- If there is urethral obstruction and a catheter cannot be passed then intravenous urography Radiography: intravenous urography may be required.
- Cystoscopy Cystoscopy: transurethral cystoscopy/vaginoscopy or urethroscopy may be available in some hospitals.
- Can be useful in the investigation of urinary tract disease Ultrasonography: bladder and urinary tract , but operator dependent - contrast radiographs often better for lower urinary tract.
- Examination of bladder for presence of mass or urolithiasis.
- Difficult to evaluate urethra.
- Examination of prostate Ultrasonography: prostate for pathology which may be compressing urethra.
- Possible ultrasound guidance, eg aspirates Fine needle aspirate: ultrasound-guided or biopsies Biopsy: ultrasound-guided.
- Evaluate regional lymph nodes.
- Look for renal pelvis dilatation.
- Collection of a urine sample Urine collection: freeflow is essential in the investigation of dysuria.
- Complete urinalysis Urinalysis: overview, including specific gravity Urinalysis: specific gravity.
- Look for inflammatory or infectious dysuria by examination of the sample for presence of:
- Red blood cells Urinalysis: red blood cells. Comparison of a free catch and cystocentesis sample can help localizing the source of bleeding (although iatrogenic hematuria can occur during cystocentesis Cystocentesis).
- White blood cells Urinalysis: white blood cell.
- Protein Urinalysis: protein.
- Bacteriuria (the presence of bacteriuria can be present in healthy animals so the finding of bacteriuria does not always indicate urinary tract infection).
Remember that a voided urine sample will not help to localize the site of inflammation.
- Obtain a urine sample preferably by cystocentesis Cystocentesis for culture in all cases of dysuria Urinalysis: bacteriology.
- Of urine sediment Urinalysis: centrifuge sediment , prostatic wash Cytology: prostatic wash or ejaculate for evidence of neoplasia.
- Prostatic wash Prostate flush.
- Fine needle aspirate of prostate (percutaneous +/- ultrasound guidance) Biopsy: prostate ) if the prostatic wash is not diagnostic.
- Also look for crystals which may be seen if uroliths are present, but crystals alone do not confirm or definitively identify urolithiasis.
- Bladder distension can result in stretching of tight junctions (this can become irreversible).
- Prolonged back pressure on the kidneys due to urethral obstruction can result in acute renal failure Kidney: acute kidney injury (AKI) and permanent renal damage.
- Renal damage may result from chronic urinary tract infections which may result from lower urinary tract disease.
- Urethral stricture can occur after severe urethral trauma, for example after obstruction.