Congenital Abnormalities of the Urinary Tract
(Common)
The most frequent congenital defects and abnormalities of the genitourinary tract are hydronephrosis, undescended testicles (cryptorchidism), hypospadias and epispadias.
Congenital Abnormalities of the Kidney
Hydronephrosis
o Hydronephrosis is distention and dilation of the renal pelvis, usually caused by obstruction of the free flow of urine from the kidney.
o loin or flank pain
o kidney may be palpable on examination.
o may cause renal failure
Absence of one kidney
o Congenital aplasia
o Failure to develop one kidney
o Can be found during ulatrasound examination, CT scanning and Pyelogram studies
o Ureter absent
o No ureteric orifice found during cystoscopy
o Or ureter and renal pelvis are present but the kidney absent
Investigations
CT Urography
o CT Urography has almost completely replaced conventional excretory urography, popularly called IVU.
o With the current multi-slice scanner, especially 64-slice CT scanners, it is possible to obtain high-quality images of the kidneys, ureters and bladder,
Renal Ectopia
o Kidney does not ascend
o Usually near the pelvic brim ; usually left - called pelvic kidney
o If it is not symptomatic the only problem is that during the abdominal operations the pelvic kidney should not be mistaken for any abnormal tumour and be injured
Horseshoe Kidney
o Situated usually in front of fouth lumbar vertebra
o Fused lower poles common
o Ureters angulated
o Infection
o Nephrolithiasis
o Fixed mass below umbilicus
Investigations
Intra venous pyelogram
CT scan
Scintigram
Unilateral Fusion
o Both kidneys are in one loin
o Usually fused
o Ureter of the lower kidney crosses the midline to enter the bladder on the contralateral side.
o Both renal pelves may lie one above each other medial to the renal parenchyma(unilateral long kidney - or the pelvis of the crossed kidney faces laterally (unilateral S-shaped kidney)
Congenital cystic kidneys - polycystic kidneys
o Hereditary
o Autosomal dominant trait
o Not usually detectable until the second or third decades of life and never manifests before the age of 30
o Irregular upper quadrant mass
o Loin pain
o Haematuria
o Infection
o Hypertension
o Uraemia
Investigations
CT scan
usgm
IVP
Simple Renal Cyst
o Common
o may be Multiple
o Diagnosed on ultrasound
o Rarely requires treatment
o Treat only if causing obstruction
Aberrent renal vessels
o Two or more renal arteries are most common on the left
o Functional end arteries - infarction if divided
o Veins can be divided because they have collaterals
Two Right Renal Arteries
Congenital abnormalities of the renal pelvis and ureter
Duplication of a renal pelvis
o double renal pelvis
o Common
o Usually unilateral
Duplication of a ureter
The ureters usually join before they reach the bladder
Less commonly the ureters open indepedently into the bladder
Congenital megaureter
o dilatation of the ureter
Congenital Defects of the bladder
Ectopia vesicae - exstrophy of the bladder
o Easily recognised at birth
o Umbilicus absent, protruding due to the intraabdominal pressure
o In addition epispadias
o Mons and clitoris bifid
o In the neonate the bladder should be covered with Saran Wrap or clingfilm to prevent trauma to the delicate mucosa
Congenital abnormalities of the urethra and penis
Meatal Stenosis
o Congenital stenosis of the external urethral meatus - normally the narrowest part of the male urethra
o Associated with phimosis - at times pin hole meatus
o Back pressure effects
o Spraying, dribbling
Congenital Urethral Stricture
o Rare
Congenital valves of the posterior urethra
o Folds of urothelium
o Obstuction in boys
o Within prostatic urethra
o Catheter will pass easily
o Micturating cystourethrogram done
o Pass catheter
Hypospadias
o Most common urethral abnormality
o Glandular hypospadias
o Coronal hypospadias
o Penile and penoscrotal hypospadias
o Perineal hypospadias
o Avoid circumcision
Abnormalities of the testes and scrotum
Incompletely Descended Testis
o Testis is not present in the scrotum
o In about 4 % of all newborns
o 50% descend during the first month of life
o The genitals of all newborns must be examined
o May be associated with inguinal hernia
o Should be corrected well before puberty
o Otherwise atrophies
o The testis may be found at various positions
Retractile Testis
o Sometimes the testis intermittently disappears upwards.
o This phenomenon is called 'retractile testis'.
o wait for the boy to grow
o careful followup
o if the testis prefers to stay higher or if the testis is under tension when brought down, surgical correction is recommended.
Ectopic testis
The sites of ectopic testes are
o At the superficial inguinal ring.
o In the perineum
o At the root of the penis
o In the feroral ring
Phimosis
o At birth foreskin adherent to the surface of the glans penis
o Separate spontaneously with time
o Can wait for 4 years to separate
o Gentle retraction at bath permitted
o Forcible retractions injure
