Urinary Stones

Question 1

What are the risk factors for urinary stones

Answer 1

1) Dehydration (major RF)
2) Diet : increase intake of PTN/oxalate
3) Urine stasis: ex, BPH / neurogenic bladder
4) Infection: causing struvite stone
5) underlying metabolic condition:
- Ca oxalate , Ca phosphate stone: hypercalciuria/ hyperphosphaturia / hyperuricosuria / hypocitraturia
- Uric acid stone: hyperuricosuria
- Cystine stone: hereditary cystinuria
- xanthine stone: hereditary xanthinuria

Question 2

What are the types of urinary stones?

Answer 2

1. Calcium containing stones: 80%
   -Ca oxalate. - Ca P (esp in
   hyperpara)
2. Struvite stones
3. Uric acid stones
4. Cystine
5. Xanthine

Question 3

The only radiolucent stone is …..

Answer 3

Uric acid stone

Question 4

What are the complications of urinary stones ?

Answer 4

1. Obstruction
2. Infection
3. Deterioration of renal function
4. Metaplasia of epithelium (transitional transforms to squamous)

Question 5

What are the investigations done for urinary stones?

Answer 5

1. KUB : detect 90% of stones (radio opaque)
2. Spiral CT :most sensitive
3. IVU
4. US
5. Diuretic Renogran
6. Lab:
   - Urine analysis: hematuria / infection
   - Stone analysis
   - blood tests: ex: increase uric acid or Ca

Question 6

What is the management for renal calculi?

Answer 6

1. Ttt of acute renal colic: parentral analgesics ( NSAID -opiates)/ antiemetics &IV fluid / antibiotics
2. Conservative ttt: by increasing fluid intake & follow up ??? Stone < 5 mm / no back pressure , infection or distal obstruction
3. Surgical management :
   ESWL ? < 2cm
   PCNL? > 2cm
   Open surgery? CI to ESWL PCNL or failure
4. Metabolic workup to prevent recurrence :
   Stone analysis
   S.P & S.Ca
   24 urine collec for : Ca / Oxalate / Uric acid / citrate

Question 7

Management of ureteral calculi?

Answer 7

1. Ttt of acute renal colic : same as renal
2. Conservative ttt : same + alpha blocker ( to relax ureter)
3. Surgical management:
   ESWL: < 1cm
   URS: > 1cm
   Open surgery: rarely indicated (assoc pathology like stricture failed /URS )
4. Metabolic work up same

Question 8

DD Of radioopaque shadow in Rt hypochondrium ?

Answer 8

1. Renal stone
2. GB stone
3. Phelpbolith /FB
4. Calcified mesentric LN
5. Calcified costal cartilage
6. Fracture transverse process of lumbar vertebrae

Question 9

CI to ESWL?

Answer 9

1. Bleeding disorder
2. HTN (uncontrolled)
3. UTI

Same in PCNL

4. Pregnancy
5. distal obstruction

Question 10

Complications of ESWL?

Answer 10

1. Transient attacks of hematuria
2. Failure of disintegrating the stone
3. UTI
4. Urinary tract obstruction
5. Renal hematoma

Question 11

Complications of PCNL?

Answer 11

1. Bleeding
2. Injury to adjacent organ
3. Residual stone
4. Irrigation fluid enter peritoneum or retroperitoneum

Question 12

Indications for PCNL

Answer 12

1. > 2cm
2. Hard stone: cystine, calcium oxalate ,monohudrate
3. Failure of ESWL
4. Staghorn stone

Question 13

Complications of URS (ureteroscopy)

Answer 13

1. Perforation of ureter
2. Infection
3. Migration of stone up to the kidney
4. Ureteric stricture