Neonatal & Pediatric Kidneys & Adrenals Flashcards
Kidneys are developed from embryonic parenchymal masses called ___.
renuculi
the former are called lobes and remnant lobes with incomplete fusion is termed fetal lobulation
What does a neonatal kidney look like sonographically?
large, hypoechoic renal pyramids
thin cortex, greater echogenicity than liver
sinus is hypoechoic and indistinct
arcuate arteries at base of pyramids and are punctate and echogenic
Why is the renal cortex so echogenic in a neonate?
due to glomerulus primarily in the cortex
What are the normal measurements for the bladder wall in a neonate?
<3mm
when empty, <5mm
What does a neonatal adrenal gland look like sonographically?
thin echogenic medulla
thicker hypoechoic rim
What are common causes of hydronephrosis?
obstruction, reflux, and abnormal muscle development
What is the sonographic appearance of hydronephrosis?
visible renal parenchyma, central cystic component, small peripheral cysts budding off large central cyst, visualization dilated ureter
What is the most common type of obstruction of the upper urinary tract?
uteropelvic junction obstruction
What is associated with UPJ obstruction?
multicystic dysplastic kidney
bilateral envolvement may occur (UPJ) along with contralateral multicystic dysplasic kidney or vesicoureteral reflux
What is the sonographic finding with UPJ obstruction?
pelvocalyceal dilation without ureteral dilation, when obstruction pronounced dilated renal pelvis extends inferiorly and medialy, if vescicoureteral reflux or primary megaureter is present ureter may be dilated
What may an abscess or lymphoma cause in relation to the ureter?
obstruction to ureter, presence of primary megaureter, atresia, ectopic ureter may be cause of obstruction, mesenteric adenitis
What is mesentaric adenitis?
infammatory, ideopathic condition
enlarged mesenteric lymph nodes (can cause compression)
What does sonography show with a ureteral obstruction?
hydronephrosis and hydroureter with narrow segment of diastal ureter behind bladder; increased peristais in ureter distal to obstruction; diminished ureteral jet
What may the bladder be obstructed by?
neurogenic bladder, pelvic mass, congenital anomaly such as posterior urethral valves
What is the most common cause of bladder outlet obstruction in the male neonate?
posterior urethral valves
typically in area near prostate
What are possible causes of bladder outlet obstruction?
posterior urethral valves, pelvic mass/tumor, vesicoureteral reflux
What is the sonographic appearance of posterior urethral valves?
thickened and trabeculated bladder wall; key hole sign
What is the incidence of ectopic ureterocele?
occurs more commonly in females and more often on the left side
What is the sonographic appearance of an ectropic ureterocele?
fluid mass within bladder
Prune belly syndrome constists of the triad of what?
hypoplasia of abdominal muscles, cryptorchidism, urinary tract anomalies
What are characteristics of prune belly syndrome?
congential absence/deficiency of abdominal musculature; large hypoechoic dilated tortuous ureters; large bladder; patent urachus (pathway that connects bladder); bilateral cryptorchidism; dilated prostatic urethra
What is a serious side effect of prune belly syndrome?
severely affects patients have urethral atresia
can cause full bladder and low amniotic fluid volume
which can result in hypoplastic lungs
What is the sonographic appearance of prune belly syndrome?
dysplastic echogenic kidneys (severe pts); non-hydronephrotic kidneys with dilated ureters and a huge bladder (less severe)
wrinkled “prune like” abdomen clinically due to absent abdominal muscles
What is the most common cause of abdominal mass in a newborn?
multicystic dysplastic kidney
What is the most common cause of renal cystic disease in neonate when hydronephrosis is excluded?
multicystic dysplastic kidney
What is multicystic dysplastic kidney disease?
congential, usually sporadic, renal dysplasia thought to be secondary to severe, generalized interference with ureteral bud function during first trimester
What are the characteristics of multicystic dyplastic kindey?
collecting tubules enlarge, grossly distorting shape of kidney
remaining renal parenchyma becomes nonfunctioning
What occurs in nearly half MCDK cases?
contralateral abnormalities (UPJ obstruction or reflux)
What are the sonographic findings for MCDK?
unilateral mass resembling “cluster of grapes”; multiple discrete NON-COMMUNICATING cysts; largest cysts are on periphery; no identifiable renal pelvis
What is the typical pathologic presentation of autosomal recessie polycystic kidney disease?
diffuse enlargement, sacculations, cystic diverticula of medullary portions of kidney
When is the most severe and least severe stages seen in ARPKD?
most: neonatal stage
least: infantile to juvenile stage
What is the most common form of ARPKD?
perinatal stage
characterized by varying degrees of renal tubular dilation and hepatic fibrosis
What associated findings may be seen with ARPKD?
pulmonary hypoplasia with respiratory distress and potter facies
What is potter facies?
hypertelorism (far set eyes), micrognathia (undersized jaw), and melotia (low set ears)
What is the sonographic findings for ARPKD?
bilateral renal enlargement; diffuse increased echogenicity; loss of definition of renal sinus, medulla, cortex; microscopic cystlike appearance thoughout both kidneys (dilated renal tubules); thin peripheral hypoechoic cortex
in less severe case: hepatosplenomegaly, portal hypertension, renal parenchyma normal to echogenic
What is the normal size of renal tubules?
less than 2mm in diameter
What is autosomal dominant polycystic kidney disease?
adult dominant form of polycystic kidney disease
usually appears during middle age and rarely reported in young infants
What is the prognosis for ARPKD?
poor prognosis
What other organs may be involved with ADPKD?
cysts can also form in liver, spleen and pancreas
With ADPKD, what forms in 10-15% of patients?
cerebral berry aneurysm (saccular)
What is the sonographic appearance of ADPKD?
lack of significant renal impairment, normal AFV (inutero), multiple well defined cysts affecting both kidneys
What is the prognosis for ADPKD?
better than ARPKD
List the clinical symptoms of acute pyelonephritis.
sudden fever, flank pain, tenderness, increased WBC count
With acute pyelonephritis, where does the infection start?
infection usually begins in bladder and scends ureter into renal pelvis
What is the sonographic appearance of acute pyelonephritis?
increased echogenicity in renal pyramids; renal pelvis and ureter may be thickened; renal size slightly enlarged; abscess may form demonstrating mixed echogenic pattern
diffuse or local
What is chronic pyelonephritis?
results when repeated episodes of acute pyelonephritis cause kidney to become scarred and decreased in size
What is the sonographic appearance of chronic pyelonephritis?
irregular renal outline; echogenic renal cortex (more so than liver); pyramids difficult to differentiate from renal parnechyma