Simple renal cysts

Parapelvic cysts

Cysts associated with multiple renal neoplasms

Congenital cystic disease

Medullary cystic disease

are all classifications of what?

Thought to be retention cysts

Are relatively common

Can be located anywhere in the kidney

Are not usually clinical significant

US findings of a characteristic simple cyst

Thought to be retention cysts secondary to tubular obstruction, vascular occlusion, or focal inflammation

Also known as a renal sinus cyst

Found in the renal hilum but does not communicate with the renal collecting system

US findings of a well-defined mass with no internal septations

May obstruct the kidney so assess for hydronephrosis

Von Hippel-Lindau disease and tuberous sclerosis

Autosomal-dominant genetic disorders (genetic) that result in tumor and cyst formation in multiple areas of the body

Acquired cystic disease of dialysis

Patients on renal dialysis have shown an increased incidence of renal cysts, adenomas and renal cell carcinoma

Tuberous sclerosis

Autosomal-dominant genetic disorder that can cause multiple renal cyst as well as solid tumor formation in other areas of the body

Polycystic renal disease

Classified as infantile autosomal-recessive form or adult autosomal-dominant form

US findings

Infantile polycystic kidney disease (IPKD) fetus presents with large, echogenic kidneys-- results in fetal demise

 Adult polycystic kidney disease (APKD)

Juvenile appearance

Adult manifestation

Polycystic renal disease

adult polycystic kidney disease (APKD)

  juvenile appearance of bile duct proliferation, periportal fibrosis , portal hepatic varices and nephromegaly

  Adult  appearance of bilateral enlargement of the kidneys, multiple cysts bilaterally,

  associated abnormalites include a circle of Wills aneurysm, liver cysts, splenic cysts and pancreatic cysts

  clinical findings of advanced disease include hypertension and renal failure

30-40 years of age.. Dominate autosomal is the most common

Ressesive – rare.. 

Multicystic dysplastic kidney

Non-inherited renal dysplasia that usually occurs unilaterally

Most common palpable mass in neonates

US findings

Neonates and infants present with enlarged kidneys with one kidney containing cysts of varying sizes

Adult kidneys may also appear small and calcified as well as findings seen in the neonate

Multicystic dysplastic kidney

US findings

Neonates and infants present with enlarged kidneys with one kidney containing cysts of varying sizes with no normal renal parenchyma

Medullary sponge kidney

Rare, non-inherited, benign renal disease seen in children

Medullary cystic disease (nephronopthisis)

Recessive inherited disease seen as small, echodense kidneys

Renal cell carcinoma

Transitional cell carcinoma

Renal lymphoma

Metastases

Wilm’s tumor

Benign renal tumors

Most common of all renal tumors (hypernephroma / nephroma)

Male predominance

Occurs most often after age 60

May be bilateral

*Staging of tumor involvement is critical for patient care management

US finding of a solid, parenchymal mass that is usually not echogenic

Most common tumor of the renal collecting system

Male predominance with increased incidence with aging

Patient may present with a history of hematuria

US findings

Solid, low-echo mass in the renal pelvis

Pitfalls may be mass seen could be squamous cell tumor or adenoma, blood clot or fungus ball

Lymphomatous involvement of the kidneys secondary to, more commonly, non-Hodgkin’s lymphoma

Non- specific US findings of enlargement of the kidney with tumors being hypoechoic (Figure 10-56)

Most common primary sites are from malignant melanoma, lymphoma, or carcinoma of the lung, breast, stomach, cervix, colon, or pancreas

Also known as nephroblastoma

Most common solid renal mass of childhood

S & S of palpable abdominal mass with pain, hematuria, fever, anorexia, N/V

Associated with Beckwith-Wiedemann syndrome

US findings variable appearing tumor that often spreads beyond the renal capsule into vascular channels

exomphalos, macroglossia, gigantism, hypoglycemia—recessive inheritance

Also associated with sporatic aniridia ( no eye color) omphalocele, and hemihyperthrophy(one side of body is larger than the other)

Adenomas

Oncocytomas

US findings of  a “spokewheel” pattern of enhancement with a central scar

Angiomyolipomas (Figure 10-61)

Uncommon lesion composed mainly of fat cells, seen most often in the renal cortex

Solitary, hyperechoic mass 

Inflammation of the glomeruli

US findings of increase renal parenchymal echoes

S&S of nephrotic syndrome, hypertension, anemia and peripheral edema

Inflammation of the glomeruli that results in possible necrosis and/or cell proliferation in that structure

Define nephrotic syndrome

Associate with lupus erythematosus (body attacking itself.)

Renal S&S of hematuria, proteinuria, hypertension, RVT, & renal insufficiency

US findings of increased cortical echogenicity and renal atrophy

connective tissue disorder believed to result from an abnormal immune system—female (20-40 years old) predominance, renal involved in >50%

RVT renal vein thrombosis

Disease of the immune system

Unexplained uremia or azotemia may indicate renal dysfunction

US findings of increased echogenicity of the parenchyma with normal/increased size of kidneys

Renal damage and azotemia due to uncontrolled hypertension

US findings of small, smooth bordered kidneys

increased levels of nitrogenous products in the blood due to poor renal function. (urea)

Any condition that affects the excretory and regulatory function of the kidney(s)

May be an acute or a chronic condition

Sonography is the initial procedure to assess all patients with known or suspected renal disease

used in IVP may cause patient to go into renal failure.  If BUN and creatinine is elevated, contrast is contra-indicated

Classified as either acute or chronic

Excretory function and regulatory function is affected in both

Check lab values for abnormal BUN and creatinine

Categorized as prerenal, renal or postrenal

Abrupt, transient decrease in renal function

Etiology of acute azotemia

Parenchymal diseases

Renal vascular occlusion

Classified as pre-renal, renal, or post-renal  in etiology

liguria is often the first clinical sign of acute renal failure

Etiology of acute azotemia

  define azotemia

Parenchymal diseases

  acute glomerulonephtitis, acute interstitial nephritis, and acute tubular necrosis

Renal vascular occlusion

  renal vein thrombosis and, rarely, renal artery occlusion

Pre-renal failure would be due to hypoperfusion of the kidney

Renal would be due to renal disease of the kidney itself or renal vein thrombosis/renal artery stenosis

Post-renal would be due to outflow obstruction 

Most common medical renal disease to produce acute renal failure

US findings

Bilaterally enlarged kidneys with hyperechoic pyramids

Renal failure may be reversed

Unresolved acute disease that results in scarring and destruction of the kidney

US findings are usually of a small, shrunken echogenic kidney

Dilated renal collecting system due to obstruction

Categorized as intrinsic or extrinsic obstruction

Classifications of dilatation

Determined by extent of collecting system involvement

US findings of fluid-filled areas that conform anatomically to the infundibula, calyces, and renal pelvis

Must attempt to locate level of obstruction

Intrinsic causes of calculus, stricture, inflammation, pyelonephritis, congenital bladder neck obstruction, posterior urethral valve, ureterocele, UPJ obstruction

Extrinsic causes classified as bladder tumors carcinoma of cervix, calculi, neurogenic bladder, normal pregnancy, pelvic mass, prostatic enlargement , retroperitoneal fibrosis

Classifications

  class I small separation of the calyceal pattern known as splaying

  class II “bear-claw” effect

  class III-massive dilatation with loss of renal parenchyma

Pus is formed in an obstructed renal system

US findings of low-level echoes with a fluid debris level

Renal Carbuncle – “zit on kidney”

Partial or complete occlusion of the renal artery

May be intrinsic or extrinsic

Often due to arteriosclerosis

Parameters for assessment

Direct evaluation of the main renal artery

Indirect by evaluating the arcuate and intralobar renal arteries

Direct –RAS would demonstrate velocities > 150-190 cm/s with turbulence distal to the stenosis

  pitfall—there may be more than one renal artery

Resistive index (RI) of 0.70 has generally been accepted as the upper limit of normal

Part of the renal tissue undergoes necrosis due to a lack of blood flow

May be due to clot, tumor or obstruction

US findings of a triangular shaped mass along the peripheral border of the kidney

Sonography’s role

Aid in diagnosing

Organ rejection

Acute tubular necrosis (ATN)

Obstructive nephropathy

Extraperitoneal fluid collections

Hemorrhages or infarctions

Graft rupture

Discuss transplantation candidate profile, donor profile and surgical procedure

  Donor left kidney removed then rotated and placed in recipient’s right iliac fossa or groin region—renal artery is attached by and end-to-end anastomosis  (figure 9-87) to either the common or the external iliac artery

Within 48 hours post-transplant a baseline sonogram is performed to assess

Renal size, calyceal pattern, and extrarenal fluid collections and doppler of renal vessels

Sonographic technique

Locate organ by making transverse, supine scans from the pubis to above the level of the graft

Image organ in longitudinal and transverse with and without routine measurements

Doppler assessment should be performed  

Doppler measurements should be performed on the main renal artery, main renal vein, interlobar renal artery and arcuate artery

Renal transplant rejection

Acute tubular necrosis

Cyclosporine toxicity

Malignancy

Extraperitoneal fluid collections

Obstructive nephropathy

Most accurate diagnosis is by percutaneous needle biopsy

Types of rejection

Hyperacute, acute and chronic

US findings vary with type of rejection

Types of rejection: (1) hyperacute that occurs within hours of transplantation

  caused by vasculitis leading to thrombosis and usually graft loss

  (2)  acute rejection occurs within days to months of surgery

  is an immunologic rejection –classified as vascular vs. interstitial from.  With aggressive   therapy with anti-rejection drugs the graft may be saved

  (3)  chronic rejection—may occur months after implantation.

Acute tubular necrosis 

Usually due to ischemia during organ transfer

Can be reversed

US findings of enlarged graft with no parenchyma changes

Cyclosporine toxicity

Reaction to the antirejection drug cyclosporine A with azathioprine & steroids

Best determined by biopsy

Delayed complication of transplantation

Non-Hodgkin’s lymphoma and skin cancer are the most common type

Appear as round or oval structures with irregular, thickened walls

Correlate with clinical findings to aid in determining the etiology of the fluid

Types of fluid collection include

Lymphocele and lymph fistulas

Urinary fistula and urinoma

Perinephric abscess

Hematoma

Lymphocele image on next frame

  common complication of transplantation—may result in decrease in renal function

Urinary fistula and urinoma—leakage of urine from graft ureter or bladder union—may be free fluid or may be encapsulated

Abscess:  FUO—can compromise transplant

Hematoma:  appears as stage of bleed—associated with dropping hematocrit

S&S of anuria or severe oliguria

Multiple causes of obstruction

Identified sonographically by the presence of hydronephrosis

Multiple causes of obstruction:  ureteral necrosis, abscess, lymphocele, fungal ball, retroperitoneal fibrosis, ureteral calculous, stricture at UVJ, hemorrhage into the collecting system with clot formation

Usually occurs within the first 2 weeks following transplant

US findings of gross distortion of the graft with associated hematoma or hemorrhage

US findings

Assess for renal vein thrombosis

Calculi may form in the kidney

May remain in the kidney or travel via the ureter to the bladder

US findings

Echogenic stones that should shadow

Possible dilatation proximal to the obstruction

Bladder diverticulum

Herniation of the bladder wall

Urine filled outpouch of  the bladder wall

May retain urine, post-void

Bladder inflammation

Aka cystitis

US findings in advancing disease of thickening bladder wall

Bladder tumors

95%  are transitional cell carcinoma (TCC)

S&S of hematuria and urinary irregularity

US findings of focal thickening of the bladder wall or a lesion protruding into the lumen of the bladder