What is the Hounsfield density range of uric acid stones?
400 600 HU
600 800 HU
800 1000 HU
1000 1200 HU
Correct Answer :
A. 400 600 HU
self-explanatory.
Related Questions
What type of stones do laxative abusers might develop?
ammonium urate
sodium urate
calcium oxalate
calcium phosphate
What type of urinary diversion carries the highest risk of stone formation?
Kock pouch
Neobladder-to-urethra diversion
Florida pouch
Indiana pouch
For how long a completely obstructed ureter could be respited with no expected permanent damage to renal functions?
2 days
2 weeks
2 months
4 6 hrs.
During pyelolithotomy for removing a staghorn urate stone; how to ensure a complete removal of calyceal branches?
by performing intra-operative ultrasonography
by performing radial nephrotomies
by performing adjunct PCLN
by taking a scout KUB film
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
What is the most favorable stone characteristic for PCNL treatment?
≥ 2 cm diameter
upper calyx location
Na.urate composition
600 - 800 HU density
What is the principal defect in renal hypercalciuria?
impaired renal tubular calcium reabsorption
excessive glomerular leak of calcium
deficiency of the enzyme xanthine oxidase
hypercalcemia
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 kind of stones is most amenable to ESWL?
cystine
brushite
Ca.oxalate monohydrate
Ca.oxalate dihydrate
What is the incidence risk of ureteral strictures following ureteroscopy?
3 6 %
12 15 %
0.4 0.8 %
0.09 0.14 %
What condition might NOT cause uric acid stones?
Tumor lysis syndrome
hypoparathyroidism
myeloproliferative disorder
Lesch-Nyhan syndrome
What is true regarding prostatic stones?
they are multiple and small in size
usually, they are voided spontaneously
they, rarely, form large stones within the peripheral zone
contrast CT is the conventional method for diagnosis
What is (are) the indication(s) of hospitalization of ureteral stone patients?
steinstrasse
a stone in ureterocele
fever, leucocytosis, pain
brushite stones
What is the preferred irrigation fluid during PCNL?
physiological saline 0.9%
glycine 1.5%
balanced salt solution
distilled water
A 24-hr urine collection of a recurrent Ca. oxalate stone former patient having Crohn`s disease might reveal:
high citrate, high oxalate
low citrate, low oxalate
high citrate, low oxalate
low citrate, high oxalate
In what kind of renal stones do antibiotics help most?
indinavir
magnesium ammonium phosphate
xanthine
matrix
What is false concerning obesity and urinary stone formation?
obese patients have a higher tendency for uric acid stone formation
high-protein, low-carbohydrate diet might increase the risk of stone formation and bone loss
metabolic syndrome is associated with high urinary pH
Roux-en-Y-gastric bypass surgery may increase the risk for stone formation
What is the composition of brushite stones?
calcium phosphate
calcium oxalate monohydrate
sodium urate
2,8 dihydroxyadenine
What is false concerning cystine stones?
have diagnostic hexagonal crystals
dont respond to ESWL therapy
are highly soluble in water
inherited in an autosomal recessive fashion
What is the sure diagnostic finding of Ca.oxalate stones?
chemical analysis of a recovered stone
hypercalcemia
CT finding
high breakability on ESWL
What bowel surgery could result in enteric hyperoxaluria?
right hemicolectomy
small bowel resection
Roux-en-Y gastric bypass
b & c
What does nephrocalcin do?
dissolves cystine stones
enhances nephrocalcinosis process over old scared areas
inhibits Ca.oxalate aggregation and crystallization
plays a secondary role in metastatic calcification process
As per the fixed particle theory of stone formation:
the initial step is papillary plaque formation
crystals formation occurs inside the nephron
tubular precipitates form harmless crystalluria
the attraction of organic compounds and activation crystallization is regulated by osteopontin
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 risk factor(s) promote(s) stone formation?
dehydration
metabolic disorders
congenital anomalies
all of the above
Why do patients with cystic fibrosis form stones?
because urine and body secretions are highly concentrated
due to renal leak hypercalciuria
as a result of distal renal tubular acidosis type I
because of reduced or absent of oxalobacter formigenes colonization
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 is true concerning primary hyperparathyroidism and stone formation?
orthophosphates may have a role in the treatment
hyperparathyroidectomy and levothyroxine replacement is the optimum treatment
management includes Calcium chelating agent and repeat 24hr urine collection in 3 months
surgical excision of the adenoma(s) is the treatment of choice
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 primary bladder stones?
commonly occur in patients with senile prostatic enlargement
common in children exposed to low-protein, low-phosphate diet
rarely recur after treatment
respond to ESWL