Pediatric Body

Renal

• If you do not see a kidney on one side you should keep the two major items in the differential

• Solitary kidney (other side is just absent)

  • Be sure to look throughout the pelvis and abdomen first before stating this as kidney may be ectopic

• Crossed fused renal ectopia

  • Basically the two kidneys are fused and located on one side

  • Will see abnormal tissue along the kidney which is the fused portion of the second kidney, will be more subtle than what a fused kidney looks like in horseshoe kidney for example

Calyceal Diverticulum

• Will look like simple cyst but will show strong enhancement on delayed phase which represents communication between the diverticulum and the calyx

• Layering of stones, calcium = highly suggestive of diverticulum

Ureterocele

• Looks like filling defect in bladder

Bilateral Renal Agenesis

• Suspect in newborns with pneumothorax

  • PTX raises concern for pulmonary hypoplasia

    • Pulmonary hypoplasia results from in utero oligohydraminos

      • Oligohydraminos —> renal agenesis

• US will show

  • Flattened adrenal glands

  • Decompressed bladder (no urine being made)

• Lethal

Duplicated collecting system

• Can be partial or complete but when there are two collecting systems in one kidney

• May be easy to see as they can have enlarged column of berlin

• Highly associated with ureteroceles (if you see a ureterocele you need to look for duplicated system)

• Upper moiety

  • typically has the ureterocele and becomes obstructed

  • Chronic obstruction results in cystic dysplasia and scarring

  • Upper ureter will insert ectopically

    • Will be lower and medial

• Drooping lily sign

  • Only lower moiety fills so looks like a flower

• Weigart-Meyer rule

  • the ectopic ureter will be medial and inferior

Multicystic Dysplastic Kidney

Ureteropelvic junction obstruction

• Basically what the name says, there is an obstruction at the junction of the renal pelvis and ureter

• Causes

  • Idiopathic

  • Compression by a vessel (can be a very small vessel and does not actually look like compression, just looks like the vessel is crossing the UPJ)

    • Look for accessory renal arteries which may be doing this

• On imaging looks like severe hydro with dilatation of the ureter proximally

• On multiphase urogram will likely not seen contrast in the affected ureter because there an obstruction but can see it in the calyces

• Treatment

  • May resolve

  • Pyeloplasty (basically cut out the obstructed part and sew the other shit back together)

• Can lead to renal cystic dysplasia

  • Basically chronic obstruction causes normal renal parenchyma to be replaced by communicating cysts which then becomes scar tissue

  • Different from MCDK because MCDK is congenital and renal pelvis is congenitally absent

Posterior Urethral Valves

• Only males

• If identified pre-natally will have oligohydramnios with pulmonary hypoplasia

• Keyhole appearance

  • Due to dilatation of the bladder and posterior urethra

• The bladder will typically have irregular contour due to chronic outlet obstruction - all because th ebladder is contracting against a closed door

  • Elongated

  • Trabeculated

  • Maybe some diverticula

• Findinsg associated with preserving renal function & therefore better prognosis

  • Urinary ascites

  • Severe unilateral vesicoureteral reflux

  • Urinoma

  • Large bladder diverticula

  • These all basically act to relieve high pressure within the bladder

  • Basically these are all protective features

• Treated surgically

Prune Belly Syndrome (Eagle-Barrett Syndrome)

• Findings

  • Hydroureteronephrosis

  • Cryptorchidism

  • Abdominal wall laxity

References:

• Case courtesy of Henry Knipe, Radiopaedia.org, rID: 41934