198. Congenital Pediatric GU Anomalies

Question 1

Multicystic Dysplastic Kidney (MCDK)

• what is it
• dx
• pathology
• mgmt

Answer 1

ureteric bud does not connect/contact metanephric blastema

Dx: US: 1 - lack of reniform shape, 2 - multiple peripheral cysts w/o clear connection “Bunch of grapes”, 3 - lack of central cyst

Path: multiple non-communicating cysts, no normal renal parenchyma, ureteral/pelvic atresia

Mgmt: naturally involutes

Question 2

Hydronephrosis/Urinary Tract Dilation

• what is it
• how does ureter normally develop
• dx
• urologic manifestations of urinary tract dilation

Answer 2

Abnormal ureteral development
Normal: Day 37-40: ureter loses lumen as meso converts to metanephros, regains lumen from midpoint outwards (last to reopen are ureteropelvic + ureterovesicular junctions)

Hydronephros: dilation of urinary tract due to some degree of past/current obstruction

dx: antenatal US
manifestations: Isolated Antenatal Hydronephros, Ureteropelvic Junction obstruction, Vesicoureteral Reflux, MCDK

Question 3

Ureteropelvic Junction (UPJ) Obstruction

• Demographics
• Etiology
• Presentation infants vs. children
• Mgmt

Answer 3

M > F, L kidney > Right kidney, 10-40% bilateral
E: Intrinsic: aperistaltic segment, narrowing, polyps near UPJ
Extrinsic: high insertion, ureteral kindking, crosses vessel (intermittent blocking)

CP: infants: prenatal US, febrile UTI; Children: DIETL’S Crisis (intermittent pain with diuresis (crossing vessel etiology)), febrile UTI, hematuria, stones

Mgmt: open pyeloplasty: recreate good drainage (can do laparascopic/robotic pyeloplasty too)

Question 4

Vesicoureteral Reflux (VUR)

• what is it
• presentation
• demographics
• dx
• pathophys
• mgmt

Answer 4

What: reflux of urine up 1/both ureters to kidney due to UVJ intramural tunnel too short or lack of detrusor support (need long tunnel to act as flat valve during bladder contraction) or caudal displacement of ureteric bud (high insertion = more lateral = shorter tunnel)
CP: symptomatic UTI, found incidentally on UTD evaluation
Demo: younger age, whites > AA, F > M (more commonly affected by UTI)
Dx: VCUG (fill bladder with contrast, image while voiding), DMSA (top down contrast, look for kidney effects)
PPhys: VUR + UTIs = renal scars = reflux nephropathy (accumulation of renal scarring) = ESRD [most common cause of renal scarring]
Mgmt: prevent UTIs = less scars = less ESRD (prophylactic ABx - TMP/SMX)
surgical: lengthening intramural tunnel 5:1 ratio (does not prevent UTIs)

Question 5

Ureteral Duplication

• what is it
• US
• Weigert-Meyer Rule

Answer 5

Two ureteral buds (can be normal)
US: kidney clefting

WMR: ureters invert positions as they fuse with UG sinus
Upper moiety: ureter inserts INFERIOR + MEDIAL, more commonly OBSTRUCTS
Lower moiety: ureter inserts SUPERIOR + LATERAL, more commonly REFLUXES

Question 6

Posterior Urethral Valve

• what is it
• presentation
• dx
• mgmt

Answer 6

Abnormal insertion of wolffian ducts into post urethra - valve where urethra crosses UG diaphragm - creates ballooning and obstruction during urination
CP: prenatal: bilateral hydronephrosis, thick walled bladder, dilated posterior urethra, oligohydramnios;; postnatal (Urinary retention, renal insufficiency, pulm insufficiency - oligohydramnios, UTIs, poor urinary stream)
Dx: US, VCUG (valve leaflets)

Mgmt: initial: catheterization

early: endoscopic valve ablation/diversion
late: manage ESRD/Incontinence/Hydronephrosis

Question 7

Hypospadias

• what is it
• etiology
• dx
• assoc
• mgmt

Answer 7

embryonic failure of urethral plate to tubularize
etiology: evniro, endo, androgen insensitivity, arrested development
dx: dorsal hood (incomplete foreskin), chordee (downward bend in penis), deviated median raphe, flattened ventral glans
assoc: undescended testis, hernia, DSD
Mgmt: surgical correction (outpt, uses native tissue)

Question 8

Undescended Testis

• Dx
• Mgmt

Answer 8

dx: PE
Mgmt: spontaneous descent (rare after 6mo)
low infertility risk if unilateral
high seminoma cancer risk!
low risk testicular torsion

Question 9

Pediatric Hernia/Hydrocele

• most common etiology
• dx
• mgmt
• indications for surgery

Answer 9

E: patent processus vaginalis
Dx: Hx (change in size throughout day), PE (transillumination)
Mgmt: tend to go away by 18 months if spontaneous

Surgery: true hernia (inguinal bulge), evidence of communicating hydrocele (changes size, progressive enlargement), lack of resolution by 18 mo