Radsci 350 Urinary System Part 2

Front 1

Renal Calculi

Back 1

Calcifications within the urinary system. Typically, these are concentrations of calcium, uric acid and/or salts.

Front 2

Formation of renal calculi

Back 2

The cause varies and often reflects an underlying metabolic abnormality, such as hypercalcemia or any cause of increased calcium excretion in the urine. May also be caused by urinary stasis and infection. UTI's and decreased fluid intake may also lead to renal calculi.

Front 3

Composition of renal calculi

Back 3

-Calcium
-Phosphate; form staghorn calculi from a bacterial infection
-Oxalate
-Magnesium ammonium phosphate
-Uric acid (uncontrolled diabetes will cause these type of stones)
-Cystine (breakdown of proteins, look like air bubbles)
***All stones are radiopaque except for cystine stones***

Front 4

Location of renal calculi

Back 4

Stones typcially develop in the minor calyces and get lodged in the ureters at the uretero pelvic junction (UPJ), pelvic brim and the ureteral cystic junction (UCJ). Stones in the ureters result from downward movement of kidney stones.

Front 5

Imaging renal calculi

Back 5

80% of renal stones contain enough calcium to be visible on plain abdominal x-rays. Non-contrast CT, IVP, US and MRI may also be used to diagnose renal stones.

Front 6

Treatment for renal calculi

Back 6

Medications may be introduced into the upper urinary tract by means of a percutaneous catheter to dissolve large kidney stones into smaller pieces. Lithotripsy is useful for stones in the kidney.
Cystoscopic retreival may be used for stones in the lower ureters. If the stones is <5mm in size, then increase fluid intake should push it through.

Front 7

Radiographic Appearance of renal calculi

Back 7

Most renal stones are radiopaque calcifications that are visible on abdominal films. Excretory urograms demontrate stones as lucent filling defects in an opacified renal pelvis. Sometimes, the stones may fill the renal pelvices entirely. Strictures in the ureters may also be detected on excretory urography films.

Front 8

Urinary Tract Obstruction Causes

Back 8

Adults: urinary calculi, pelvic tumors, urethral strictures, enlarged prostate gland.
Children: congenital malformations including ureteropelvic junction narrowing, ureterocele, retrocaval ureter, posterior urethral valve

Front 9

Locations of Urinary tract obstructions

Back 9

Obstruction usually occurs at normal points of narrowing, such as the ureteropelvic and ureterovesical junctions, the bladder neck, and the urethral meatus.

Front 10

Hydronephrosis

Back 10

This is distention of the pelvis and calyces of the kidney. It is caused by excess amounts of fluid in the kidney. This results in an enlarged kidney leading to thinning of the cortex.

Front 11

Radiographic Appearance of Hydronephrosis

Back 11

The kidney appears enlarged and the calyces are moderately dilated. The ureter proximal to the obstruction will also appear dilated. Increased pressure will lead to calyceal "clubbing." Gradual enlargement may continue until visualization of normal kidney anatomy is obliterated.

Front 12

Treatment of hydronephrosis

Back 12

Decompressing the urinary tract to prevent parenchymal damage and possible ureteral rupture. Percutaneous nephrostomy will provide drainage and may help demonstrate the site of obstruction. May also place stents in the ureters to bypass the obstruction and allow proper drainage.

Front 13

Renal Cyst

Back 13

Fluid filled unilocular masses in the kidneys. They vary in size and may occur at single or multiple sites in one or both kidneys.

Front 14

Radiographic Appearance of renal cysts

Back 14

The margins appear on nephrotomography as a very thin, smooth, radiopaque rim surrounding the bulging lucent cyst (beak sign). Cysts may cause displacement of adjacent portions of the pelvicalyceal system.

Front 15

Cause of renal cyst

Back 15

Renal cysts occur when a renal tubule becomes plugged up resulting in a bulging cyst filled with a collection of urine.

Front 16

Treatment for renal cysts

Back 16

Simple cysts typically resolve on their own, but may place pressure on surrounding structures if they are large. Needle puncture should be performed if there is an atypical appearance. Following puncture, a catheter can be placed for drainage. Injection of iodine or alcohol may obliterate the cyst.

Front 17

Polycystic Disease

Back 17

An inherited disorder in which many cysts cause enlargement of the kidney and renal impairment. Usually bilateral and can lead to hydronephrosis.

Front 18

Radiographic appearance of polycystic disease

Back 18

Excretory urography demonstrates enlarged kidneys with a multilobulated contour. The pelvic and infundibular structures are elongated and often displaced around larger cysts. The nephrogram typically has a mottled or Swiss cheese pattern caused by the presence of innumerable lucent cysts. Cannot use contrast media due to known decreased kidney function.

Front 19

Complications of polycystic disease

Back 19

Patients tend to have liver cysts as well. This may lead to liver disfunction due to the increased pressure placed on the vessels. Affects the vascular, nervous and lymphatic structures surrounding the area. Increases the propensity for berry aneurysms due to the pressure and backup of blood in the vascular system.

Front 20

Treatment for polycystic disease

Back 20

No curative treatment. May give dialysis treatments, pain medications, anti-inflammatories. Fluid and electrolyte control may help ease the pain as well as drainage of some of the cysts. Renal transplantation may be considered.

Front 21

Renal Carcinoma

Back 21

This is the most common malignant renal cancer and may not be recognized until it has metastasized. Tumors usually originate in the tubular epithelium of the renal cortex.

Front 22

Cause of renal carcinoma

Back 22

Unknown etiology, but predisposing situations may include: chronic inflammation, smoking and chemicals found in food.

Front 23

Signs and symptoms of renal carcinoma

Back 23

Occurs predominantly in patients older than 40. Painless hematuria, flank pain and possible palpable abdominal mass.

Front 24

Imaging/diagnosis of renal carcinoma

Back 24

Selective renal arteriography, US, MR and CT. Biopsy may be performed; however, the tumor is typically well encapsulated so biopsy may cause rupture and spread. Nephrotomogram demonstrates lucent, well-demarcated renal mass with thick walls and displacement and distortion of the affected kidney.

Front 25

Treatment for renal carcinoma

Back 25

Radical nephrectomy (removal of everything), radiation therapy and possible chemotherapy (although relatively insensitive), laser ablation. Poor prognosis.

Front 26

Radiographic appearance of renal cell carcinoma (hypernephroma)

Back 26

Hypernephromas typically produce urographic evidence of locatlized bulging or generalized renal enlargement. The tumor initially causes elongation of adjacent calyces leading to distortion, narrowing or obliteration of part or all of the collecting system..

Front 27

Nephroblastoma (Wilms' Tumor)

Back 27

Malignant renal tumor, the most common abdominal tumor of infancy/childhood. The lesion arises from embryonic renal tissue. It may be bilateral and it tends to become very large and appear as a palpable mass. This is a fast growing tumor that is most common in children under the age of 5.

Front 28

Radiographic Appearance of Wilms' Tumor

Back 28

The intrarenal tumor causes pronounced distortion and displacement of the pelvicalyceal system. On abdominal radiographs, other structures appear displaced.

Front 29

Treatment of Wilms' Tumor

Back 29

Surgical resection, radiation therapy and chemo result in an 85% cure rate in patients with Wilms' tumor.

Front 30

Bladder Carcinoma

Back 30

Most commonly originates in the epithelium, aka urothelial carcinoma. Usually seen in men over the age of 50.

Front 31

Risk factors for bladder carcinoma

Back 31

Caucasian males, smoking, food/products, industrial chemicals, irritants, parasitic infection (men in Egypt)

Front 32

Radiographic Appearance of bladder carcinoma

Back 32

Appears as a well-encapsulated tumor with fingerlike projections into the bladder. Plain radiographs may demonstrate calcifications on the surface of the tumor. CT is the imaging of choice and deomonstrates a mass projecting into the bladder lumen or as focal thickening of the bladder wall. IVP and cystoscopy are also useful in demostrating bladder carcinoma.

Front 33

Treatment for bladder carcinoma

Back 33

Resection and bladder removal, intercavitary radiation. May regrow after resection, so they may remove the entire bladder and reconnect the ureters to the ilium. May also use part of the ilium as the "bladder" to allow mostly normal urinary function. Radiation and chemo to follow surgical intervention. High survival rate because the cancer is usually contained within the bladder.

Front 34

Acute Renal Failure

Back 34

Rapid deterioration in kidney function.

Front 35

Cause of renal failure

Back 35

Pre-renal failure: caused by decreased blood flow to the kidneys; stenosis, trauma, plaque, hemorrhage, dehydration.
Post-renal failure: caused by obstruction of outflow; large stone, trauma, impingement from another structure.

Front 36

Radiographic Appearance of renal failure

Back 36

Bilaterally enlarged, smooth kidneys are suggestive of acute renal failure. Small kidneys usually indicate chronic preexisting kidney disease. Delayed and prolonged nephrogram indicates acute renal failure.

Front 37

Treatment options for acute renal failure

Back 37

Medication and dialysis to eliminate waste out of the blood.

Front 38

Chronic Renal Failure

Back 38

This is the end result of gradual progressive loss of kidney function. Uremia (excessive uria in the system) causes a toxic effect to vascular and nervous systems.

Front 39

Diagnosis of chronic renal failure

Back 39

Contrast media does not concentrate well requiring the use of tomograpms. US is the initial procedure followed by blood tests to determine BUN and creatinine levels.

Front 40

Treatment for chronic renal failure

Back 40

Initial goal is to slow the nephron loss and minimize complications. Antihypertensive drugs and balance of intake and output of fluids. Dialysis is required and possible kidney transplant.

Front 41

Complications with renal failure

Back 41

Chronic renal failure is the loss of function and deterioration of the kidney. May be acute renal failure that was not resolved. Once damage has occurred, the kidneys cannot regain function. Dialysis is required to maintain potassium/calcium levels, drain fluid and filter blood and fluid.

Front 42

Complications with renal failure: twitching

Back 42

Loss of renal function can lead to buildup of uremia in the system. This is increased potassium levels which means a decrease of calcium in the vascular structures. Potassium causes contraction of musculature and lack of calcium causes an inability for muscle relaxation. Edema will also occur due to the inability of the kidneys to filter fluid leading to CHF. Normal kidneys also release erythropoetin; loss of that function can lead to anemia.