urology

Question 1

what does KUB X-ray mean?

Answer 1

kidney ureter bladder xray

Question 2

what are intrinsic risk factors for renal stones?

Answer 2

• age 20-40
• sex male
• race- Caucasian
• gene - happens in 25% of patients

Question 3

what are extrinsic risk factors for renal stones?

Answer 3

• diet and fluid- high salt diet
• climate- hot climate
• occupation- factory workers working in hot conditions are more likely

Question 4

what are the genetic risk factors?

Answer 4

• hyper calciuric patients- this can be polygenic or monogenic
• familial renal tubular acidosis
• cytinugia- autosomal recessive
• xanthine and dihydroxyadenine

Question 5

what are the different types of salts that can form stones?

Answer 5

• Calcium Oxalate
  60%
• Calcium Phosphate
  20%
• Urate
  10%
• Struvite
  8%
• Cystine
  1%

Question 6

what are the small molecules that can inhibit stone formation?

Answer 6

Citrate
Phytate
Pyrophosphate
Magnesium

they do this by binding to calcium and stopping it from aggregating

Question 7

what are some urinary macromolecules that can inhibit kidney stone formation?

Answer 7

• Urinary prothrombin fragment 1
• Nephrocalcin
• osteopontin
• Tamm-Horsfall glycoprotein
• Bikunin
  UNOT-B

Question 8

which anatomical factors that cause urine stasis and increase the risk of stone formation?

Answer 8

• calyceal diverticulum- small pouches in the kidney that do not empty freely
• anatomical variant such as ureteric junction obstruction

Question 9

what are randalls plaques?

Answer 9

subepithelial calcification of the renal papilla.

They act as an anchor for calcium oxalate crystals and are considered to be a predisposing factor for renal stone formation.

Question 10

what is the presentation of kidney stones?

Answer 10

• Pain- acute cholic- loin to groin pain
• Haematuria (visible, non-visible)
• Urinary tract infection

Question 11

what is the treatment for kidney stones?

Answer 11

Medical
Medical Expulsive Therapy - MET
Chemolysis - Uric acid stones

Shock Wave Lithotripsy - ESWL
Ureteroscopy & Ureterorenoscopy
Percutaneous Surgery - PCNL
Laparoscopic Surgery
Open Surgery

Question 12

what is the treatment of a episode?

Answer 12

NSAIDs
Analgesics
Opiates
Antiemetics

Question 13

what is a gold standard for imaging renal stones?

Answer 13

non contrast CT scan

Question 14

What is the chance of passing the kidney stone based on stone position?

Answer 14

Prox ureter-> 22%
Mid ureter-> 46%
Distal ureter-> 71%

Question 15

what is the chance of passing the stone based on stone size?

Answer 15

– <4mm  80%
– 4-6mm  59%
– >6mm  21%

Question 16

what is the VUJ?

Answer 16

vesicleuroteric junction- where the ureters meet the bladder

Question 17

what percentage of VUJ stones <5mm are spntaneously passed?

Answer 17

94%

- that’s why its sometimes good to take a conservative approach

Question 18

when would yo treat a kidney stone?

Answer 18

• if patient is in uncontrolled and persistent pain
• kidney is deteriorating in function
• patient only has one kidney

Question 19

how does ESWL work

Answer 19

• a spike in energy initially breaks the stone, then a fall will break it down into smaller pieces

Question 20

How effective is ESWL depending on the kidney position?

Answer 20

Renal Pelvis= 86-9%
Upper pole= 71-83%
Interpolar= 23-84%
Lower pole= 37-68%

Question 21

what does steinstrasse mean?

Answer 21

its when stones form one on top of another ‘stone street’ at the end of the ureter

Question 22

what are the complications of ESWL?

Answer 22

Steinstrasse
Residual fragment re-growth
Fragment colic
Sepsis
Macro haematuria
Renal haematoma Symptomaic
Renal haematoma Asymptomatic
Bowel perforation
Liver & splenic haematoma

Question 23

what is URS

Answer 23

form of minimally invasive surgery using a small telescope that is passed through the urethra and into the ureter to remove a stone

Question 24

what is the effect of URS depending on position?

Answer 24

distal- 94%
mid- 86%
proxima- 81%

Question 25

when would percutaneous surgery be used to remove a kidney stone?

Answer 25

• when the stone is >2cm

- when the stone is complex

Question 26

what are examples of complex kidney issues that would require PCNL?

Answer 26

Multiple stones
Lower pole - unfavourable features
Calyceal diverticulum
Ectopic kidney
Horseshoe
Obese
Abnormal anatomy
Difficult retrograde access
Encrusted stents

Question 27

what type of stones are you at risk of with chemotherapy?

Answer 27

Chemotherapy and cell death can increase uric acid levels. In this acute setting the uric acid stones are unlikely to be coated with calcium and will therefore be radiolucent.

Question 28

which stones are associated with inherited metabolic disorders?

Answer 28

Cystine

Question 29

what is the first line analgesic for renal colic?

Answer 29

• 75mg diclofenac IM

Question 30

what does Periureteric fat stranding on a non contrast CT indicate?

Answer 30

spontaneously passed stone

Question 31

what are struvite stones composed of?

Answer 31

ammonium magnesium phosphate, triple phosphate

Question 32

which bacteria predispose to renal struvite stones?

Answer 32

they form in alkaline urine (ammonia producing bacteria such as Ureaplasma urealyticum and Proteus therefore predispose)

Question 33

what is the treatment for obstructive urinary calculi with infection?

Answer 33

the stone is obstructing the ureter and causing hydronephrosis (ultrasound scan shows dilation of the renal pelvis)

These patients are at risk of urosepsis so urgent renal decompression via a ureteric stent or percutaneous nephrostomy should be performed to relieve the obstruction. They must also receive antibiotics for the upper urinary tract infection.

Nifedipine may be used in some patients with small, uncomplicated renal stones. It relaxes the ureters and aids passing of the renal stone

Question 34

what is the use of Urinary alkalinization?

Answer 34

to prevent the formation of uric acid stones.