What type of stones is most effectively treated with PCNL?
Ca.oxalate monohydrate
cystine
matrix
Ca.oxalate dihydrate
Correct Answer :
C. matrix
unlike other listed stones, matrix stones are non-crystalline, thus dont respond to ESWL. PCNL washes it out better than ureteroscopy.
Related Questions
What is the treatment of choice for a 15 mm stone in the lower calyx with a narrow infundibulum?
ESWL
PCNL
radial nephrolithotomy
pyelolithotomy with ureteral stenting
What is false concerning the use of antibiotics in stone patients?
they are mandatory when urine shows ≥ 10 WBCs/hpf in symptomatic patients
they aim at treating pyonephrosis and urosepsis
they should cover Escherichia coli and Staphylococcus, Enterobacter, Proteus, and Klebsiella species
All of the above
What is the most appropriate antibiotic class for prophylaxis before urologic surgery?
aminoglycosides
macrolides
cephalosporins
fluoroquinolones
What type of stones is soft, resilient, composed of mucoproteins of urine and serum?
matrix
indinavir
brushite
2,8 dihydroxyadenine
What is the most common organism that might complicate PCNL?
Proteus mirabilis
E. coli
Pseudomonas aeruginosa
Staphylococcus epidermidis
What sequence of ureteral parts represents the most to least favorable stone response to ESWL treatment?
upper, lower, mid
lower, upper, mid
mid, upper, lower
mid, lower, upper
What is false regarding DJ ureteral stents?
can be introduced from the bladder or kidney or any part of the ureter`s course
the standard adult size is 32 cm long, 4 mm calibre
might result in encrustations and ureteral obstruction
might result in ureteral dilation
What could high level of sulfate in 24-hr. urine collection mean?
dissolving homogenous nucleation
high tendency to form cystine sulfate stones
indicates the amount of dietary protein
post ESWL therapy
What is (are) true concerning ESWL?
a stone is fragmented when the force of the shockwaves overcomes the tensile strength of the stone
fragmentation occurs as a result of compressive and tensile forces, erosion, shearing, spalling, and cavitation
the generation of compressive and tensile forces and cavitation are thought to be the most important
all of the above
What is false concerning cystine stones?
result from an inherited defect of renal tubular reabsorption of cysteine
characteristically, urate and cysteine stone are radiolucent
cysteine is a dibasic amino acid
on plain X-ray, cysteine stones exhibit ground-glass appearance
What could high dietary protein result in?
increase urinary calcium, oxalate, and uric acid excretion
decrease urinary calcium; but increase oxalate, and uric acid excretion
increased urinary calcium and uric acid; but decrease oxalate excretion
decreased urinary calcium, oxalate, and uric acid excretion
What does NOT appear as a filling defect in the renal pelvis on IVU?
fungal ball
radiolucent stone
urothelial growth
upper end of DJ ureteral stent
What is false concerning staghorn calculus?
commonly unilateral
commonly due to repeated infections
urate stones are the second most common cause of staghorn calculi
ESWL monotherapy with ureteral stenting is the ideal treatment
Which of the following is a relative contra-indication to ESWL?
renal insufficiency
active urinary tract infection
uncorrected bleeding disorder
third trimester pregnancy
Two weeks of prolonged wound drainage after a non-stented Anderson-Hynes pyeloplasty. What would be next step in the management?
watchful waiting
open surgical correction
IVU with possible endoscopic ureteral stenting
perc. nephrostomy tube insertion
How can the effectiveness of ESWL treatment session be enhanced?
by ensuring optimal coupling of the patient to the lithotripter
by running the treatment at a slower rate (60 shocks/min)
by running the treatment with general anesthesia
by all of the above
What kind of stones is more likely to recur with infections if not removed completely?
urate
triple phosphate
oxalate monohydrate
matrix
What type of shockwaves is generated by spark-gap technology?
piezoelectric
electrohydraulic
electromagnetic
microexplosive
What is false concerning struvite stones?
the commonest to form staghorn giant calculi
formed by urease producing bacteria
antibiotics have a role in the treatment
form at the two extremes of urinary pH range
What is the treatment of choice for a 15 mm stone in a mid calyceal diverticulum?
ESWL
PCNL with fulguration of the diverticulum
ureteroscopy with fulguration of the diverticulum
pyelolithotomy with diverticulectomy
What is the composition of brushite stones?
calcium phosphate
calcium oxalate monohydrate
sodium urate
2,8 dihydroxyadenine
Which of the following dietary advice is recommended for Ca.oxalate stone formers?
limit beef, chicken, pork, eggs, fish, shellfish, and other animal proteins
limit beans, nuts, chocolate, coffee, dark green vegetables, and soda
limit canned, packaged, and fast foods
limit milk, cheese, and other dairy products
What risk factor(s) promote(s) stone formation?
dehydration
metabolic disorders
congenital anomalies
all of the above
What is the preferred irrigation fluid during PCNL?
physiological saline 0.9%
glycine 1.5%
balanced salt solution
distilled water
In what kind of renal stones do antibiotics help most?
indinavir
magnesium ammonium phosphate
xanthine
matrix
What is false regarding hypomagnesuric calcium nephrolithiasis?
it is characterized by low urinary magnesium and citrate
magnesium increases renal tubular citrate resorption
diarrheal is a remarkable side effect of magnesium therapy
potassium-magnesium preparations might restore urinary magnesium and citrate levels
What type of urinary diversion carries the highest risk of stone formation?
Kock pouch
Neobladder-to-urethra diversion
Florida pouch
Indiana pouch
What is the preferred drug for medical expulsive therapy for lower ureteral stones?
furosemide
tamsulosin
nifedipine
diclofenac
Invasive intervention in stone patients is NOT indicated in the following condition:
stone size
unrelieved obstruction
infection and septicemia
recurrent stone formation
What is false concerning prostatic stones?
composed of calcium phosphate and calcium carbonate
the vast majority are asymptomatic
most of the calculi are found in the transitional zone
they dont affect PSA levels