Urology Flashcards
What is nephrolithiasis, ureterolithiasis and cystolithiasis?
Nephrolithiasis – kidney stone
Ureterolithiasis – ureteric stone
Cystolithiasis – bladder stone
What are the risk factors for stone formation?
Obesity
Dehydration
Hypercalciuria, Hyperparathyroidism and hypercalcaemia
Metabolic conditions – cystinuria, high dietary oxalate
Renal tubular acidosis
Medullary sponge kidney and polycystic kidney disease
Beryllium or cadmium exposure
Gout and ileostomies (loss of bicarbonate and fluids results in acidotic urine)
Drugs – diuretics, steroids, acetazolamide, theophylline
What causes stone formation?
Proteus species common cause of stones
Abnormal calcium, phosphate, urate and cystine levels in the body
Pregnancy and right sided stones
What are the main types of stones that form and what pH do they form under?
Calcium oxalate (most common) occurs in variable urine pH
Calcium Phosphate (5-10%) due to normal pH or alkalotic urine
Struvite (ammonium magnesium phosphate) (5-10%) due to infections in the urinary system and alkaline pH
Urate (radiolucent) due to persistently acidic urine
Cystine (rare) due to genetic disorders and occurs in normal pH urine
What are the clinical feature of renal stones?
Sever urinary colic pain in the flanks that can radiate to the groin (testicle and labia) Haematuria but visible and invisible Painful urination Urinary urgency Nausea and vomiting Sweating Hydronephrosis of affected kidney
How should suspected renal stones be investigated?
Urinalysis with dipstick and culture
Renal function + bone profile (including urate)
Routine inflammatory markers for signs of infection
Group and save, crossmatch and clotting if surgery likely
USS to assess for stones and hydronephrosis
CT KUB (non-contrast) within 14 hours of admission)
How should pain be managed in renal colic?
Analgesia – NSAIDS, most commonly diclofenac IM/PR or ibuprofen
What might suggest a more invasive management is needed for dealing with renal stones?
More invasive management may be required if ureteric obstruction, renal developmental abnormality, and previous renal transplant.
What surgical emergency can stones cause and how is it managed?
Ureteric obstruction due to stones + infection is surgical emergency, must release compression – nephrostomy tube placement, insertion of ureteric catheters and ureteric stent placements.
When is a conservative approach to stones indicated?
If stone is small (<5mm) will probably pass spontaneously if not it may need to be removed
What are the surgical options for renal stones and when are they indicated?
- ESWL (extra corporeal shock wave Lithotripsy) – external shock waves, can cause solid organ damage and patient required analgesia. Indicated in stone burden <2cm in aggregate
- PCNL Percutaneous nephrolithotomy – access gain to the renal collecting system then intra corporal lithotripsy is performed and stone fragments removed. Indicated in complex renal calculi and staghorn calculi.
- Flexible Ureteroscopy passed into the renal pelvis, indicated when lithotripsy is contraindicated e.g. pregnant females, stent usually left in situ for 4 weeks.
- Open surgery
What advice/drugs can we give to prevent renal stone formation?
- Thiazide diuretics to increase distal tubular calcium resorption
- Increase fluid intake
- Increase citrate intake
- Limit sodium intake
- Avoid vitamin C supplements
- Limit animal protein
- Limiting soft drinks
- Oxalate stones – cholestyramine or pyridoxine
- Uric acid stones – allopurinol or urinary alkalization with oral bicarbonate or acetazolamide
What is an epididymal cyst?
Epididymal cysts are the most common cause of scrotal swellings seen in primary care.
What are the clinical features of an epidiymal cyst?
Separate from the body of the testicle
Found posterior to the testicle
Diagnosis may be confirmed by ultrasound
What conditions are epididymal cysts associated with?
Associated with polycystic kidney disease, cystic fibrosis, and von Hippel-Lindau syndrome
How should epidiymal cysts be managed?
Management – supportive but surgical removal or sclerotherapy may be attempted for larger or symptomatic cysts
What is a hydrocele and what are the two types?
A hydrocele describes the accumulation of fluid within the tunica vaginalis. They can be divided into communicating and non-communicating:
• Communicating: caused by patency of the processus vaginalis allowing peritoneal fluid to drain down into the scrotum. Communicating hydroceles are common in Newborn males (clinically apparent in 5-10%) and usually resolve within the first few months of life
• Non-communicating: caused by excessive fluid production within the tunica vaginalis
What can cause hydroceles?
Epididymo-orchitis
Testicular torsion
Testicular tumours
What are the clinical features of a hydrocele?
Soft, non-tender swelling of the hemi-scrotum. Usually anterior to and below the testicle
the swelling is confined to the scrotum, you can get ‘above’ the mass on examination
Transilluminates with a pen torch
The testis may be difficult to palpate if the hydrocele is large
What investigations should be done in a hydrocele?
Diagnosis may be clinical but ultrasound is required if there is any doubt about the diagnosis or if the underlying testis cannot be palpated.
How are hydroceles managed?
Infantile hydroceles are generally repaired if they do not resolve spontaneously by the age of 1-2 years.
In adults a conservative approach may be taken depending on the severity of the presentation.
What is a varicocele?
A varicocele is an abnormal enlargement of the testicular veins. They are usually asymptomatic but may be important as they are associated with infertility.
What are the clinical features of a varicocele?
Varicoceles are much more common on the left side (> 80%).
Classically described as a ‘bag of worms’
Subfertility
Sometimes painful
How should varicoceles be investigated?
Ultrasound with Doppler studies
