Urolithiasis

Question 1

Types of renal stones

Answer 1

Calcium oxalate or phosphate - 80%
Uric acid, magnesium ammonium phosphate (Struvite) and cystine

Question 2

Features of struvite stones

Answer 2

Often lead to large staghorn calculi which involve the renal pelvis and extend to at least 2 renal calyces.

Question 3

What predisposed struvite stones

Answer 3

Recurrent upper UTIs

Question 4

Symptoms of renal stones

Answer 4

Loin to groin pain as calculi pass through narrowings. Severe intermittant pain, haematuria, nausea and vomiting

Question 5

Complications of renal stones

Answer 5

Chronic inflammation, ulceration and long standing irritation can cause metastatic changes. Infarction of stone can casue sepsis. Mucosal injury causing haematuria. Obstruction

Question 6

What classifies as small stones

Answer 6

<5mm

Question 7

Treatment of small stones

Answer 7

Watchful waiting if there is not current obstruction, or medical expulsive therapy for calculi in distal ureter

Question 8

Treatment for large stones

Answer 8

Percutaneous nephrolithotomy, ureteroscopy, shock wave lithotropy

Question 9

Treatment of choice for pregnant women

Answer 9

Ureteroscopy

Question 10

Causes of obstruction

Answer 10

Renal calculi, tumours, inflammation, benign prostatic hyperplasia, pregnancy, uterine prolapse, congenital causes

Question 11

Hydronephros features caused by obstruction

Answer 11

High pressure proximal to obstruction resulting in dilation of renal pelvis and calyces, with blunting of renal papillae and atrophy

Question 12

Complications of hydronephros

Answer 12

Cortical atrophy, tubular atrophy and interstitial fibrosis