Renal stones

Question 1

Symptoms

Answer 1

Renal colic, loin to groin pain, nausea and vomiting
+/- infection, UTI, pyelonephritis
Haematuria, proteinuria, sterile pyuria, anuria.

Question 2

Investigations

Answer 2

FBC, U+E, CRP, urine dip ++ blood

Non contrast CT KUB within 14 hours, asap if fever or only 1 kidney. Rule out AAA.

Question 3

Treatment

Answer 3

Analgesic- diclofenac 100mg PR is drug of choice.
Fluids.
Nifedipine or Tamsulosin.
Antibiotics if infection e.g. tazocin, gentamicin.

Stones <5mm- 95% spontaneously pass within 4 weeks
Other interventions: extracorpeal shockwave lithotripsy, percutaneous nephrolithotomy, uretoscopy.

Question 4

Indications for treatment:

1) loin pain, stone >1cm, no hydronephrosis
2) loin pain, fever, stone 7mm + hydronephrosis
3) loin pain, staghorn calculus 2.3cm
4) Not passing stone in pregnant woman

Answer 4

1) shockwave lithotripsy
2) percutaneous nephrostomy (drain insertion, hydronephrosis means system needs urgent surgical decompression)
3) percutaneous nephrolithotomy
4) ureteroscopy

Question 5

Prevention

Answer 5

Drink plenty, normal calcium intake
For calcium stones- take thiazide diuretic to decrease calcium excretion.
For uric acid stones- allopurinol

Question 6

Types of renal stone

Answer 6

Calcium oxalate, caused by hypercalciuria, most common type, radio-opaque spiky stones.

Calcium phosphate- smooth large radio-opaque stones

Urate stones- radio-lucent, smooth brown stones

Struvite- formed from magnesium, ammonium and phosphate. Urease produced bacteria, associated with chronic infection, see staghorn calculus.

Cysteine- associated with inherited recessive disorder

Question 7

Hydronephrosis- causes of unilateral and bilateral

Answer 7

Swelling of kidney due to build up of urine tat cannot drain into the bladder.
Unilateral- ureteric obstruction, calculi, tumour, aberrant renal vessels
Bilateral- stenosis of urethra, prostatic enlargement, extensive bladder tumour, retro peritoneal fibrosis

Question 8

Hydronephrosis- investigations and treatments

Answer 8

USS, IVU (intravenous urogram), anterograde/retrograde pyelography.
CT KUB.
Management: Acute surgical decompression. Nephrostomy tube to drain, if chronic ureteric stent/pyeloplasty.