CUA GL 2017 Investigation and Management of Ant detected Hydronephrosis Flashcards
What is the differential for AHN?
Transient primary hydronephrosis > UPJO> VUR> UVJO> primary non-obstructive megaureter
Describe APD diameter in 2nd and thrid trimester for mild, moderate and severe AHN?
MILD : 2nd( 4-7), 3rd(7-9)
MODERATE : (7-10), (9-15)
SEVERE : (>10), (>15)
What are the 5 grade of SFU AHN?
0 = normal/resolved 1 = pyelectasis 2 = pyelectasis and one or morre major calyceal dilatation 3 = pyelectasis with dilatation of all major calyces 4= pyelectasis with parenchymal thinning compared to contralateral kidney
What is megacystis ? give me the equation
Fetal bladder sagittal length in mm = gestational age in weeks + 2
What percentage of patients with mild, moderate or severe AHN have pathology post op?
mild = 12% moderate = 45% Severe = 88%
T/F: VUR rates among patients with mild, moderate, and severe prenatal HN are not significantly different.
TRUE
What is considered abnormal APD in third trimester by definition?
> 4mm but most centers look at 7mm or more given high false positives if you use >4mm
Other than physical exam what should you do in a baby born with AHN>
UA, serum creatinine for severe bilateral HN or abnormal renal echogenicity, solitary kidney
How long should you wait before obtaining baby serum creatinine? why?
2 days, because before then could be maternal
Why would you not want to do a RBUS in the first two days of life ?
Neonatal oliguria would lead you to underestimate HN. dont delay in cases of PUV as you need imaging right away
When should you do your post natal RBUS?
Sooner for HGHN : within a week
Can wait a bit more for LGHN: a few weeks
Describe a good VCUG
scout view to assess for spine abnormality/ constipation/ stones, Do not use a balloon catheter, the amount of urine removed recorded, gravity fill bladder until the first void, record bladder capacity, voiding views of urethra and post void views of the bladder. delayed images after post void if there is reflux into a dilated system. two fill void cycles will increase detection of VUR
Describe the well tempered renogram protocol
hydration, bladder catheterized, timely administration of lasix,
What can affect the results of MAG-3 renal scan?
poor hydration, massively dilated kidney, full bladder, dilated distal ureter
What study should be used to assess split renal function in neonates or premature infants?
DMSA since it is not influenced by immature GFR
- A 2-month-old male infant with an antenatal history of left moderate to severe hydronephrosis has a postnatal ultrasound at 24 hours of life demonstrating mild hydronephrosis. A follow-up US at 2 months demonstrates left severe hydronephrosis. This can be explained by:
a. intermittent changing hydronephrosis consistent with VUR.
b. physiologic oliguria in the newborn.
c. worsening obstruction.
d. ureterocele disproportion.
e. none of the above.
Physiologic oliguria in the newborn. It is important to keep in mind that a postnatal ultrasound examination performed within the first 48 hours of life may not yet demonstrate hydronephrosis or may underestimate the degree of hydronephrosis secondary to physiologic oliguria.
Which infants should go on CAP ?
HGHN, VUR, hydroureter, ureterocele.
What can happen if you use sulfamethaxazole or nitrofurantoin in neonates?
kernicterus and hemolytic anemia respectively.
What do you do if you got a kid with SFU G3/4, APD>15mm?
RBUS soon( after 2 days of life) within 2 weeks for sure, VCUG, MAG-3, CAP. In absence of pathology repeat RBUS and MAG-3 in 3 months. If no improvement keep FU, UPJO would manifest by 18 months of life.
What do you do for SFU G1/2 or APD<10mm (LGHN)?
First US within first month of life then another 6 months later then annual. VCUG and MAG-3 not needed unless worsening HN. FU until at least 18 months.
What are strong indications for surgery in AHN?
loss of DRF>5 % on FU
worsening HN with worsening Drainage times,
flank pain or vomiting in older children with fluid intake
