Obstructive Uropathy Flashcards
What does pressure build-up cause when there is an obstruction?
Back-pressure
Areas proximal will swell with urine
What is hydronephrosis?
Swelling of the kidney due to accumulation of fluid
What is vesicoureteral reflux?
Urine refluxing from the bladder back into ureters
What is post-renal AKI?
Reduced kidney function due to obstructive uropathy
What is pre-renal AKI?
Reduced kidney function due to hypoperfusion of the kidneys
What can cause hypoperfusion of the kidneys?
Dehydration
Sepsis
Acute blood loss
What is renal AKI?
Damage within the kidney itself causing reduced kidney function
What can cause renal AKI?
Glomerulonephritis
Nephrotoxic medications
How do upper tract obstructions present? (in the ureters)
Loin to groin or flank pain
Reduced or no urine output
Vomiting
Impaired renal function on blood tests (raised creatinine)
How do lower tract obstructions present? (in the bladder or urethra)
Difficulty or inability to pass urine
Urine retention
Impaired renal function on blood tests
What imaging is used in diagnosing obstructive uropathy?
Ultrasound
What are the common causes of upper urinary tract obstruction?
- Kidney stones
- Tumours
- Ureter strictures (scar tissue narrowing tube)
- Retroperitoneal fibrosis (scar tissue in retroperitoneal space)
- Bladder cancer
- Ureterocele
What are the common causes of lower urinary tract obstruction?
- BPH
- Prostate cancer
- Bladder cancer
- Urethral strictures
- Neurogenic bladder
What is neurogenic bladder?
Abnormal function of the nerves innervating the bladder and urethra
Leads to over/underactivity of the detrusor and sphincter muscles of the urethra
What are the key causes of neurogenic bladder?
- MS
- Diabetes
- Stroke
- Parkinson’s
- Brain or spinal cord injury
- Spina bifida
What problems can neurogenic bladder lead to?
- Urge incontinence
- Increased bladder pressure
- Obstructive uropathy
How is obstructive uropathy managed?
Removing or bypassing obstruction
Nephrostomy
Urethral/Suprapubic catheter
What are the complications of obstructive uropathy?
Pain
AKI (post-renal)
CKD
Infection
Hydronephrosis
Urinary retention and bladder distention
Overflow incontinence of urine
What happens in hydronephrosis?
Renal pelvis and calyces swell due to obstruction
What causes idiopathic hydronephrosis?
Narrowing at the pelviureteric junction
Narrowing can be congenital or develop later
How is idiopathic hydronephrosis treated?
Pyeloplasty
What imaging is used for diagnosis of hydronephrosis?
Ultrasound
CT scan
Intravenous urogram
How is hydronephrosis treated?
Treat underlying cause
Pressure can be relieved with:
- Percutaneous nephrostomy inserting tube into ureter, through skin then kidney
- Antegrade ureteric stent inserting catheter into ureter, through kidney
