Download MBBS Surgery Presentations 31 Kidney And Ureters Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) 1st Year, 2nd Year, 3rd Year and Final year Surgery 31 Kidney And Ureters PPT-Powerpoint Presentations and lecture notes


Kidney and Ureters :

Agenesis, Horseshoe kidneys,

congenital cysts, Megaureter,

Ectopic ureter, Ureterocele

Dept Of Surgery

Bilateral Renal Agenesis

? Bilateral Renal Agenesis was first recognized in 1671 by

Wolfstrigel


? Can occur secondary to a defect of the wolffian duct, ureteric

bud, or metanephric blastema

? Bilateral agenesis occurs in 1 of every 4000 births

? Male predominance


? 40% of the affected infants are stillborn

? Children who are born alive do not survive beyond 48 hours

because of respiratory distress associated with pulmonary

hypoplasia

? The adrenal glands are usually normally positioned

? Characteristic Potter facies and presence of oligohydramnios are

pathognomonic

? Complete ureteral atresia is observed in slightly more than 50%

of affected individuals

Potter's facial appearance
Diagnosis

? The characteristic Potter facies and the presence of

oligohydramnios are pathognomonic and should alert for

this severe urinary malformation.

? Amnion nodosum--smal white, keratinized nodules found

on the surface of the amniotic sac--may also suggest this

anomaly

? Anuria after the first 24 hours without distention of the

bladder should suggest renal agenesis

Diagnosis

? BRA has been detected in higher proportion in cryptophthalmos

or Frazer's syndrome, Klinefelter's syndrome , Kallmann's

syndrome, esophageal atresia.

? Renal ultrasonography confirm the presence or absence of

urine within these structures.

? Absence of uptake of the radionuclide in the renal fossa above

background activity confirms the diagnosis of BRA.

? Umbilical artery catheterization and an aortogram defines the

absence of renal arteries and kidneys.
Unilateral Renal Agenesis

? There are no tell tale signs (as with BRA) that suggest an

absent kidney .

? Diagnosis not suspected unless careful examination of the

external and internal genitalia uncovers an abnormality

that is associated with renal agenesis or an imaging study is

done.

? Unilateral agenesis occurs once in 1100 births

? Males predominate in a ratio of 1.8:1

? More frequent on the left side

? Ipsilateral ureter is completely absent in about half

of the patients

? Structures derived from the m?llerian or wolffian

duct are most often anomalous

? Anomalies of other organ systems involve the

cardiovascular (30%), gastrointestinal (25%), and

musculoskeletal (14%) systems
Unilateral renal agenesis to be associated with other

urologic abnormalities in 48% of patients

? Primary vesicoureteral reflux (28%)

? Obstructive megaureter (11%)

? Ureteropelvic junction obstruction (3%)

Diagnosis

? No specific symptoms heralding an absent kidney

? The diagnosis should be suspected during a physical

examination when the vas deferens or body and tail of the

epididymis is missing or hypoplastic vagina is associated with a

unicornuate or bicornuate uterus

? Radionuclide imaging

? No clear-cut evidence that patients with a solitary kidney

have an increased susceptibility to other diseases


Horseshoe kidneys

? Most common of all renal fusion anomalies

? Occurs in 0.25% of the population

? fusion occurs before the kidneys have rotated on

their long axis

The lower poles of the two kidneys touch and fuse as they cross the iliac arteries


? In 95% of patients, the kidneys join at the lower pole; in a

small number, an isthmus connects both upper poles instead

? Calyces normal in number, are atypical in orientation

? Ureter may insert high on the renal pelvis and lie laterally

? Blood supply to the horseshoe kidney can be quite variable


Arteriogram showing a multiplicity of arteries supplying kidney arising from

aorta and common iliac arteries

? UPJ obstruction, causing hydronephrosis, occurs in

one third of individuals

? 60% patients remain asymptomatic for aprox. 10

years




Associated Anomalies

Diagnosis

? Excretory urogram
Prognosis

? 13% have persistent urinary infection or pain
? 17% develop recurrent calculi
? Renal carcinoma has been reported within a horseshoe

kidney in 123 patients

? Incidence of Wilms' tumor in horseshoe kidneys is more

than twice

Congenital cysts

? Kidney is one of the MC

sites in body for cysts

? Arise from the nephrons

and collecting ducts after

they have formed


Cystic Diseases of the Kidney

? Multicystic refers to a dysplastic entity

? Polycystic most inherited, all without dysplasia and all

with nephrons throughout the kidney

? Many of the polycystic kidney disease entities progress

to renal failure


`Snowstorm' appearance of infantile polycystic

disease

Ectopic Kidney

? Kidney not located in usual position
? 1 in 1,000 births, but only about one in 10 of these

are ever diagnosed; up to 10% bilateral

Most common:

? Horseshoe Kidney
? Unilateral renal agenesis
? Pelvic kidney

(Left kidney more likely to be abnormal)


Ectopic Kidney

? Function is general y normal initial y
? Abnormal position leads to obstruction in 50% of

ectopic kidneys

? Increased risk UTI, kidney stones, VUR
? Frequently associated with abnormalities of other

organ systems (uterine, cardiac, skeletal)

Ectopic Kidney Locations


Ectopic Kidney

(simple renal ectopia)

Mega ureter

? Ureters wider than 7 to 8 mm
? Normal ureteral diameter is rarely greater than 5 mm
? Primary MGU is 2-4 times more common in boys than girls
? Slight predilection (1.6 to 4.5 times) for the left side
? Bilateral in approximately 25% of patients
? In 10% to 15% of children contralateral kidney may be absent or

dysplastic


Three major classifications of megaureter based on primary and secondary causes

Pathophysiology

? Distal end of the ureter, as it becomes intramural and

subsequently submucosal, rearranges the muscular layers in its

wall.

? All layers become longitudinally oriented

? Ureteral adventitia fuses to the bladder trigone by attachment to

Waldeyer's sheath

? Sympathetic and parasympathetic innervation to the distal ureter

and UVJ area is believed to modulate primarily ureteral peristalsis
Diagnosis

Ultrasound
? Distinguishes MGU from UPJ obstruction based on the

presence or absence of a dilated ureter

VCUG
? to rule out reflux

Renal scintigraphy
? Provides objective, reproducible parameters of function

and obstruction

Whitaker's perfusion test & ureteral opening pressure
? To evaluate obstruction, but their invasiveness and

requirement for anaesthesia are drawbacks in children

Magnetic resonance urography


Magnetic resonance urogram showing obstruction at the right ureterovesical

junction

Management

Primary Refluxing Megaureter
? Medical management is often the initial approach

? Surgery

? Endoscopic subureteric injection, is recommended for

persistent high-grade reflux in older children

? Reconstructive surgery of a dilated ureter

? distal ureterostomy for unilateral reflux
? vesicostomy for bilateral disease
? Secondary Refluxing or Obstructive Megaureter

? Management of secondary MGUs is initially directed at their

root cause

? Primary "Dilated" Nonrefluxing Megaureter:

Nonobstructive versus Obstructive

? Expectant management is preferred
? Antibiotic suppression & radiologic surveillance is appropriate

in most cases

? Surgical correction

? Surgical Options

? Plication or infolding for moderately dilated ureter

Complications

Persistent reflux and obstruction
Postoperative VUR
Ectopic ureter

? Ureter whose orifice terminates anywhere other

than the normal trigonal position

? Lateral ectopia : an orifice more cranial and lateral

than normal

? Caudal ectopia : orifice is more medial and distal

than the normal position

? 80% are associated with a duplicated collecting system
? Females :

? More than 80% are duplicated
? Urethra and vestibule are the most common sites

? Males:

? most ectopic ureters drain single systems
? posterior urethra is the most common site

? Drainage into the genital tract involves the seminal vesicle

three times more often than the ejaculatory duct and vas
deferens combined


Ureterocele

(outpouching of ureter as it enters bladder)

This post was last modified on 08 April 2022