4. Congenital anomalies of the kidney and ureter; Urge incontinency Flashcards
Congenital anomalies of the kidney
Simple cyst Polycystic kidney Multicystic kidney Medullary sponge kidney Renal agenesis Duplex kidney Ectopic kidneys Horshoe kidney
Simple cyst
Cyst within or on the border of the kidney, lined by single layer of cuboidal epithelium
containing transudate fluid. May originate from a nephron.
Usually asymptomatic.
Can produce abdominal pain, hematuria secondary to
rupture, HTN, or renal pelvis obstruction.
If tumor is suspected needle biopsy can be performed.
Polycystic kidney
Autosomal recessive.
PKHD1 gene
• Perinatal form: Oligohydramnios due to lack of normal urine production by the fetus. Infant will suffer from respiratory distress due to pulmonary hypoplasia
(amniotic fluid is responsible for lung development). 50% die within 2 months.
• Juvenile form: Renal failure and HTN. Renal transplant is required.
Autosomal dominant PKD1 or PKD2 gene mutations Chronic kidney disease or hypertension appears in adulthood. Berry aneurysms Mitral valve prolapse Hepatic cysts too.
Medullary sponge kidney
Congenital deformation of the renal medulla consisting of multiple dilations of the
collecting ducts in the papillae.
Usually bilateral, mostly benign. There is a slight predisposition to
calcium-phospate stones, HTN and UTIs.
IV-urography is used to diagnose. Contrast fills the dilated collecting ducts.
Medullary cystic kidney disease
Similar to sponge kidney, only it is not benign and causes progressive scarring and renal failure in mid adulthood.
Renal agenesis
Complete absence of 1 or both kidneys. There is a failure of the ureteral bud formation of the Wolfian duct.
Unilateral: Compensatory hyperplasia
Bilateral: olighydramnios and pulmonary hypoplasia. Don’t live longer than 2 days.
Duplex kidney
2 separate pelvicalyceal systems and ureters.
Usually asymptomatic. There might be hydronephrosis of the lower pole segment.
There is a predisposition to UTI and stones.
Heminephrectomy can be performed.
Renal ectopia
The kidneys are not in the normal position (renal fossa).
• Crossed ectopia: Kidney found on opposite side of where its ureter inserts.
Often fused with the crossed kidney lying inferior.
• Crossed fused ectopia: 85% of the crossed kidneys become fused with the kidney on its normal side.
• Pelvic kidney
• Thoracic kidney
The ectopic kidney is usually smaller.
Usually asymptomatic. Slight predisposition to stones.
Horseshoe kidney
Connected to each other via the
lower pole. 30% are asymptomatic.
Ureteropelvic junction obstruction can occur due to high insertion of the
ureter into the pelvis and its abnormal course over the isthmus ! hydronephrosis.
List the Congenital anomalies of the ureter (5)
Ectopic ureter
Ureterocele
Ureteropelvic junction obstruction
Vesicoureteral reflux
Megaureter
Ectopic ureter
A ureter whose orifice does not insert to the usual position in the bladder.
- 80% are associated with duplicated systems
- 20% are single ectopic ureters with an absent hemitrigone.
Most common sites of insertion
- females is the posterior urethra, vestibule and vagina.
- males posterior urethra and seminal vesicles.
Most ectopic ureters drain the kidneys with minimal function.
Symptoms:
• Urinary incontinence (most important cause)
• Recurrent UTIs
• Abdominal pain
• Failure to thrive
- Hydronephrosis, reflux.
Diagnosis: Carefull inspection of vagina and vestibule. IV urography can show dilated
collecting system.
Treatment: Heminephrectomy of non-functioning part or ureteral re-implantation.
Ureterocele
Cystic dilation of terminal ureter.
If it is large enough it can cause obstruction of the bladder neck or contralateral ureteral orifice, hydronephrosis.
Symptoms:
• Incontinence due to hindrance of normal sphincter function
• UTIs
• Abdominal pain
• Failure to thrive
- hydronephrosis
Treatment: Surgical resection or incision.
Ureteropelvic junction obstruction
Stricture of ureteropelvic junction:
• Intrinsic lesion of the circular smooth muscle of the UPJ
• Extrinsic compression by aberrant vessel
• Obstruction secondary to reflux resulting in kinking of the ureter
Symptoms:
• UTIs
• Abdominal pain (w/ palpable abdominal mass)
• Failure to thrive
• Hematuria
Treatment: Anderson-Hynes pyeloplasty: Resection of hydronephrotic pyelum and
stenotic part of ureter.
Vesicoureteral reflux,
cause
symptoms
treatment
Retrograde flow of urine from the bladder to upper urinary tract.
The ureters have 3 muscular layers; inner and outer longitudinal and middle circular,
that propels the urine forward in response to stretch.
• Primary reflux: Deficiency of the longitudinal muscles of the intravesicle ureter.
• Secondary reflux: Bladder anatomic or functional obstruction.
o Posterior urethral valves
o Neurogenic bladder
Symptoms: • 75% are asymptomatic • UTI • Abdominal pain Diagnosed with voiding cystography. Treatment: Surgery reimplantation or endoscopic injection of collagen behind the ureter.
Megaureter
Dilated ureter.
• Primary obstructive MGU: Aperistaltic juxtavesicle segment
• Secondary obstructive MGU: Infravesicle obstruction (posterior urethral
valve)
• Non-obstructive MGU: UTI accompanied by bacterial endotoxins that inhibit
peristalsis
