Disorders of the kidneys

Disorders of the kidneys

Agenesis
Bilateral renal agenesis is extremely rare.
The children don’t survive.

One kidney may be absent (estimated incidence 1 in

450-1000 births).

In some cases may be because the ureteral bud
fail to develop, or fail to reach the metanephros

The ureter and vas are abscent in 50%of affacted site

It accidantaly dignose by imaging

Hypoplasia

Hypoplasia implies a small kidney.
differentiation from acquired atrophy( as post vesicoureteral) is difficult.
Such kidneys have small renal arteries & branches & are associated with hypertension, which is relieved
by nephractomy
.


Dysplasia & multicystic kidney

Renal dysplasia is histologic diagnosis (abnormal

metanephric differentiation) the kidney may be small or large in size & contain local ,diffuse or segmentally
arrange primitive structures, it may affect all or only part of the kidney,

Cystic dysplasia :cyst of various sizes present

Multicystic kidney when the entire kidney is dysplastic with preponderance of cysts

multicystic dysplastic kidney.

Is most common renal cystic diseaes and second cause of abdominal mass after PUJ obustraction
-Usually unilateral
-nonhereditary
-the ureter is usually absent or atretic.

it may develop because of faulty union of the nephron with the collecting system.

The only finding is the discovery of irregular mass in the flank.

Diagnosis by U/S

if the physician feel that the proper diagnosis has been made, no treatment is necessary.

If there is doubt about the diagnosis, nephrectomy is

considered the procedure of choice.

Polycystic kidney disease

Classified as autosomal dominant (adult) &
autosomal recessive (infantile).

When polycystic kidney disease diagnosed in neonate most often recessive type,

50% of affected new born die in the 1st few hours
or days of life, the others will apparent at childhood up to13 & rarely up to 20 yr. & is bilateral.

Autosomal dominant (adult) polycystic kidney.

Almost always bilateral(95% of the cases),
symptoms not appear until after age 40 yr.

cysts of the liver, spleen, or pancreas may be noted


The kidneys are larger than normal

Etiology &pathogenesis

The evidence suggest that the cysts occur because
the defects in the development of the collecting, uriniferous tubules & in the mechanism of their joining.

As the cysts enlarge, they compress adjacent

parenchyma, destroy it by ischemia, & occlude normal tubules.
The result is progressive functional impairment.

Clinical findings

Symptoms
drag pain by the heavy kidneys
obstruction
infection
hemorrhage into a cyst.
Colicy pain due to stones or clots
Gross or microscopic hematuria may occur.
abdominal mass.
Infection (chills, fever, renal pain)
Symptums of renal failure

Signs

one or both kidneys are usually palpable.
-If infected they may be tender.
Hypertension is found in 60-70% of these patients.
Fever may be present if pyelonephritis exists or if cysts have become infected.
In the stage of uremia, anemia or loss of weight may be evident.

Laboratory finding

Anemia may be noted.

Proteinuria & microscopic or gross hematuria are the rule. Pyuria & bacteriuria are common.

About one-third of patients are uremic when first seen.

x-ray finding

By IVP the renal masses are usually enlarged & (spider leg deformity).

Ultrasound is superior to excretory urography


CT scanning 95% of cases give an accurate diagnosis.

Treatment

conservative & supportive (proflactive).
low protein diet
Good fluid intake
Physical activity is permitted but strenuous exercise is contraindicated.
Hypertension should be controlled.
Renal failure should be treated by dialysis or renal
transplant.
A large cyst compressing upper ureter causing
obstruction should be excised or aspirated.

Simple (solitary) cyst

Simple cyst of the kidney is usually unilateral & single but may be multiple & rarely bilateral.
Whether its congenital or acquired is not clear.

Pain in the flank or back, usually intermittent and dull,is not uncommon

Renal ultrasonography is noninvasive diagnostic
Technique


CT scan is diagnostic

.

Clinical finding

Pain in the flank or back, usually intermittent & dull.cyst is usully symptmatic if it is 10cm and more
If bleeding occur pain may come on abruptly & be sever.
The patient may discover mass in the abdomen,

If cyst become infected patient usually complain of pain in the flank malaise & fever.

Physical examination is usually normal, although a
flank mass may be palpated or percussed.
Tenderness in the flank may be noted if the cysts
become infected.

Laboratory finding

Urinalysis is usually normal.
Renal function tests are normal.

CT scan

Appear to be the most accurate means of differentiating renal cyst & tumor.


Differential diagnosis.

Simple cyst should be differentiate from

-carcinoma of the kidney,
-polycystic kidney disease,
-renal carbuncle,
-hydronephrosis,

Treatment

If the diagnosis can be clearly established, treatment is follow up by ultrasonography.
.

If the diagnosis is suspicious renal angiography or
needle aspiration of the cyst may be necessary.

Aspiration of the cyst or surgical excision of extrarenal part may be indicated in cases of complication like
obstruction , or infection.

Renal fusion

About 1 in 1000 individuals has some type of renal fusion,
the most common being the horseshoe kidney.
The fused renal mass almost always contain 2 excretory systems & therefore 2 ureters.

the renal tissue may be divided equally between the 2

flanks, or the entire mass may be on one side.
Even in the later case, the 2 ureters open at their proper places in the bladder.

Etiology & pathogenesis

It appears that fusion of the 2 metanephroi occurs early in embryologic life, when the kidneys lie low in the pelvis.

Horseshoe Kidney

Both kidney fused by isthmus usually through their lower poles

The pelvis lies anterior

Thus the ureter must ride over the isthmus or traverse the anterior surface of the fused kidney.


Some degree of uerteral compression may arise from
this or from obstruction by blood vessels.

Clinical features

Most patients have no symptoms.

Symptoms develop if there is complication like : uerteral obstruction,infection,ston.

Physical examination usually negative unless the
abnormally placed mass can be felt.

x-ray finding

in case of horseshoe kidney
The renal mass lower than normal
-the axes of the 2 kidneys are vertical andparallel
-the renal pelves lie on the anterior surfaces of the
kidney masses,
-the most valuable clue to the diagnosis of horseshoe
kidney is the presence of calyces in the region of lower pole point medially & lie medial to the ureter.


CT seldom necessary for the diagnosis.

Complications.

-Obstruction,
-hydronephrosis,
-stone
-infection
-tumour
Treatment.
No treatment is necessary unless obstruction or
infection is present.
Drainage may be improved by division of isthmus
If one pole is badly damaged it may require surgical resection

Ectopic kidney

Congenital ectopic kidney usually cause no symptoms
unless complications such as
uerteral obstruction or infection develop.


Simple ectopy
Refer to low kidney on the proper side that fail to ascend normally.
It may lie over the pelvic brim or in the pelvis.
rarely it may find in the chest.

Crossed ectopy without fusion.

In which the kidney lies on the opposite side of the body but is not attached to its normally placed mate.