Urology Flashcards
What gene causes sexual differentiation?
SRY gene
What needs to be functional for testosterone to become DHT
5 alpha reductase
Critical for normal male: DHT
What are the two most common forms of disorders of sexual development?
46 XX CAH- 95% have 21 hydroxylase enzyme deficiency
45X/46XY mixed gonadal dysgenesis
What do Leydig cells produce
Testosterone
What do Sertoli cells produce?
anti mullerian hormone
Name the 3 defects seen with hypospadias
Foreskin is incomplete ventrally
Urethral meatus not at tip of penis
Erections curved downward (AKA chordee)
Congenital hydronephrosis affects what percentage of pregnancies?
CH affects 1% of pregnancies (most common fetal anomaly)
no correlation between severity of congenital hydronephrosis and risk of VUR
positive correlation between severity of congenital hydronephrosis and risk of obstruction
What are the 4 most common causes of high grade congenital hydronephrosis?
PUV- posterior urethral valves
UVJO- ureterovesical junction obstruction
UPJO- ureteropelvic junction obstruction
High grade VUR
Congenital hydronephrosis and APD 7-10mm, when do they need ultrasound?
Within 1-3 months
Congenital hydronephrosis and APD >15mm, when do they need ultrasound?
Within 2 weeks
What are the signs of posterior urethral valves?
Male Keyhole sign Distended, thick walled bladder Bilateral hydronephrosis Oligohydramnios
What are the recommendations for prevention of renal stones?
Increased fluid intake
Avoid excess salt intake
Normal calcium intake
Most common solid renal mass of infant <1 or antenatal?
congenital Mesoblastic nephroma- usually benign
Tx- complete surgical excision
Most common solid renal mass if >1
Wilms
Testicular torsion versus torsion of appendix testis
Testicular torsion: Pain: severe, sudden onset of severity Nausea and vomiting: often Testis position: +/-high riding \+/- transverse lie Testis tenderness: throughout Cremasteric reflex: often absent Blue dot sign: never
Torsion of appendix testis:
Pain: milk to severe, gradual onset
Nausea and vomiting: occasional
Testis position: normal
Testis tenderness: localized to upper pole
Cremasteric reflex: often present
Blue dot sign: rarely present but pathognomonic
Name 2 indications for VCUG
Assess for:
- VUR
- PUV
Name one disadvantage of Nuclear Cystogram
Does not assess for PUV
Which renal scan detects renal scarring?
DMSA- best for differential renal function
Mag3 lasix scan tells you what 2 things?
differential renal function
Obstruction
(kidney function and drainage)
Name 4 types of urodynamics
- Voiding calendar- two day home data collection of time and volume of voids. Provides urinary frequency and functional bladder capacity. Helpful to diagnose overactive bladder
- Post residual void- US bladder scanner. Assesses bladder emptying
- uroflowmetry (velocity curve of urinary system). Assesses for urethral obstruction.
- cystometry (invasive urodynamics)- assessment of relaxation/contraction of pelvic floor muscles during bladder filling and voiding. Assess for normal pelvic floor relaxation with voiding.
90% of urinary stones contain________ as a major constituent, and 60% are composed of _________
Nearly 90% of urinary stones contain calcium as a major constituent, and 60% are composed of calcium oxalate.
What do we use to treat kidney stones
Pain- NSAIDs
80-90% of stones <5mm will pass on their own
alpha adrenergic blocker (tamsulosin) may facilitate passage
Interventional treatment: reserved for large stones
lithotripsy
extracorpeal shock wave lithotripsy
percutaneous nephrostolithotomy
what are signs of low grade congenital hydronephrosis on ultrasound?
minimal hydronephrosis mild hydronephrosis SFU grade 1 or 2 Calyces not dilated APD <10mm
what are signs of high grade congenital hydronephrosis on ultrasound
moderately severe hydronephrosis severe hydronephrosis dilated calyces parenchymal thinning SFU grade III or IV APD >15mm
what is UPJO and how is it different from the other causes of significant CH
uretero-pelvic junction obstruction
significant hydronephrosis WITHOUT hydroureter
what is the postnatal management for suspected PUV (7)
stabilize if respiratory issues urgent postnatal RBUS bladder decompression (catheter) Serial serum creatinine levels Confirmatory VCUG consult nephrology (fluid, acid-base, electrolyte management) consult urology (surgical management)
what is the main cause of acquired hydronephrosis? how does it present?
UPJ obstruction
presents with recurrent abdominal pain/flank pain
recurrent pyelonephritis
vomiting (+/- pain) after increased fluid intake
what investigations would you do for UPJ obstruction
Initial: RBUS
If hydronephrosis then urology may confirm obstruction with diuretic renal scan
what is the most common non-infectious cause of daytime incontinence?
idiopathic overactive bladder
what are the treatment options for idiopathic overactive bladder?
- Treat constipation (diet/PEG 3350)
Treat UTI
observation is an option if not bothersome to family/child
timed voiding (Every 1.5-2h) - Anticholinergics (oxybutinin, tolteridine, solifenacin)
what is a duplex kidney?
kidney with 2 renal pelvises
what are patients with horseshoe kidney at risk of?
Increased risk of UPJO (only relevant if hydronephrosis)
what is the first line investigation for renal stones?
renal ultrasound
what investigation will most reliably identify small stones?
CT KUB (if confirmation required after ultrasound) but not first line
what are some dietary measures for treating kidney stones?
increased fluid intake** (dilutes urine and prevents urinary solutes from crystallizing)
decrease sodium intake **
normal dietary calcium **
citrus juice contains citrate which is a urinary inhibitor of stone formation
what is a hydrocele? how do you diagnose?
fluid around or adjacent to the testis
generally asymptomatic
diagnose with transillumination
what is the risk associated with having a hydrocele? when should you refer?
risk is development of indirect hernia
allow up to age 18 months for resolution before referral
why would you do an U/S for hydrocele (4)
to confirm scrotal testis (>6mo age)
to differentiate from inguinal hernia
to rule out testis tumor (adolescent age)
when it is associated with scrotal pain NYD
what is the initial investigation for palpable abdominal mass?
abdominal ultrasound
- to differentiate solid from cystic masses
what is the treatment for congenital mesoblastic nephroma?
complete surgical excision
what 2 congenital syndromes are associated with wilm’s tumor
50% risk of wilms tumor with
Denys Drash
WAGR
does the CPS recommend newborn male circumcision?
NO!
increased risk of STI transmission and penile cancer does not justify recommendaton of routine circumcision
how can meatal stenosis be prevented following newborn circumcision?
apply petroleum jelly to the glans for up to 6 mo following circumcision
what can be used to hasten retraction of foreskin and release adhesions?
topical steroids
what are indications for surgical consultation for circumcision (4)
scarred phimosis
recurrent balanoposthitis
recurrent UTIs
delayed retraction of the foreskin >10 yo
what investigation should be done after first febrile UTI? when should VCUG be considered?
RBUS
VCUG is reserved for those with an abnormal RBUS or if they have a 2nd febrile UTI
what is VUR
retrograde flow of urine from the bladder to the kidneys
asymptomatic, low grade VUR does not require intervention
what should you tell boys to do when collecting a midstream urine
retract retractable foreskins as contamination is very common
what is cystitis
bacteruria resulting in local “bladder” symptoms only (voiding symptoms/suprapubic or lower back pain)
what antibiotics should be used for prophylaxis for UTI
septra
nitrofurantoin
- used for no more than 3-6 months
- switch antimicrobials if urine culture shows resistant organism
- if urine shows resistance to both antibiotics then consider stopping prophylaxis rather than using broad spectrum antimicrobials
DDx painful scrotal swelling (6)
testicular torsion incarcerated inguinal hernia trauma epididymitis torsion of appendix testis intermittent testicular torsion (torsion- detorsion)
DDx painless scrotal mass (6)
tumor- firm
varicocele- bag of worms
noncommunicating hydrocele- fluid filled/transilluminates
spermatocele- localized cyst/transilluminates
reducible inguinal hernia
local insect bite
what abnormality is associated with testicular torsion?
bell clapper deformity
what are the most common testicular tumors
95% germ cell tumors- seminomas and non seminomas
what is the most common malignant testicular germ cell tumor in prepubertal children
yolk sac tumor (high AFP)
although teratoma is more common
what workup should be done for testicular tumor?
Ultrasound
Tumor markers (AFP, bHCG)
Chest x-ray
CT abdo, pelvis and chest for staging
what is the treatment for testicular tumor
orchiectomy +/- RPLND (retroperitoneal lymph node dissection) +/- chemo, radiation
what is testicular microlithiasis
uncommon condition where small clusters of calcium form in the testicles (seen on ultrasound)
- do not need further imaging but should be instructed in testicular self examination, exception = DSD
what should be on the differential for an undescended testis?
retractile testis- most common!
what is the most sensitive method for determining volume discrepancy between testes?
ultrasound
15-20% reduction in volume (hypotrophy) of a testis with varicocele is common
what is the ideal time for repair of hypospadias?
between 6-12 months
what is the treatment for primary phimosis
corticosteroid cream (betamethasone 0.1% for 6 weeks)
what are some benefits of circumcision (4)
prevention of penile cancer
reduces UTI
reduces STI (HIV)
reduced balanitis, phimosis
what are some complications of neonatal circumcision
hemorrhage wound infection glans injury urethrocutaneous fistula inadvertent circumcision of neonate with hypospadias
what is the treatment of testicular torsion
Treatment is prompt surgical exploration and detorsion.
If the testis is explored within 6 hr of torsion, up to 90% of the gonads survive.
Following detorsion, the testis is fixed in the scrotum with nonabsorbable sutures, termed scrotal orchiopexy, to prevent torsion in the future.
The contralateral testis should also be fixed
