Urinary Tract Calculi Flashcards
Define Urinary Tract Calculi?
Crystal Deposition within the urinary tract
What is Urinary Tract Calculi also known as?
Nephrolithiasis
What are the type of stones that are present in Urinary Tract Calculi?
Calcium Oxalate - Most Common
Struvite - quite common
Urate - 5%
Cysteine - 2%
What are the Metabolic Causes of Urinary Tract Calculi?
Hypercalciuria
Hyperuricaemia
Hypercystinuria
Hyperoxaluria
What are the infective causes of Urinary Tract Calculi?
Hyperuricaemia
What drugs can cause Urinary Tract Calculi?
Indinavir
What are the risk factors for Urinary Tract Calculi?
Low fluid intake
Structural urinary tract abnormalities (e.g. horseshoe kidney)
What is the epidemiology of Urinary Tract Calculi?
COMMON
2-3% of general population
3 x more common in MALES
Age group affected: 20-50 yrs
Bladder stones more common in developing contries
Upper urinary tract stones more common in industrialised countries
What are the presenting symptoms of Urinary Tract Calculi?
Often ASYMPTOMATIC Severe loin to groin pain Nausea and vomiting Urinary urgency, frequency or retention Haematuria
What are the signs of Urinary Tract Calculi?
Loin to lower abdominal tenderness
No signs of peritonism
Leaking AAA is the main differential to consider in older men
Signs of systemic sepsis if there is an obstruction and infection above the stone
What investigations for Urinary Tract Calculi?
Bloods Urine X-Ray KUB Intravenous Urography (IVU) US Non-enhanced Spiral CT Isotope Radiography
What bloods do we do for Urinary Tract Calculi?
FBC - high WCC if infection
U&Es - check renal function
Calcium
Urate Phosphate
What do we do for Urine for Urinary Tract Calculi?
Dipstick - haematuria is common
MC&S
Why do we do X-Ray KUB for Urinary Tract Calculi?
80% of kidney stones are radio-opaque
Why do we do Intravenous Urography (IVU) for Urinary Tract Calculi?
Allows visualisation of the kidneys and ureters
Why do we do an US for Urinary Tract Calculi?
May show hydronephrosis and hydroureter
Why do we do Non-enhanced Spiral CT for Urinary Tract Calculi?
Can also be used to image stones
Why do we do Isotope Radiography for Urinary Tract Calculi?
Used to assess kidney function
What is the management plan for the Acute Presentation of Urinary Tract Calculi?
Analgesia
Bed rest
Fluid replacement
Urine collection to try and retrieve any stone that has passed (most stones < 5 mm will pass spontaneously)
How do we manage an obstructed infected kidney?
It is an emergency and should be treated as soon as possible to relieve the obstruction (e.g. by placing a percutaneous nephrostomy)
How do you remove calculi for Urinary Tract Calculi?
Urethroscopy
Extracorporeal Shock-Wave Lithotripsy (ESWL)
Percutaneous Nephrolithotomy (PCNL)
How does Urethroscopy help with Urinary Tract Calculi?
A scope is passed into the bladder and up the ureter to visualise the stone
It can then be removed by a basket or broken up with a laser
If the stone can’t be removed, a JJ stent should be placed to allow urine drainage
How does Extracorporeal Shock-Wave Lithotripsy (ESWL) for Urinary Tract Calculi?
Non-invasive
An electromagnetic shockwave is focused onto the calculus to break it up into smaller fragments that can pass spontaneously
How does Percutaneous Nephrolithotomy (PCNL) for Urinary Tract Calculi?
Performed for large, complex stones (e.g. staghorn calculi)
After making a nephrostomy tract, a nephroscope is inserted, which allows disintegration and removal of stones
What is the treatment of cause for Urinary Tract Calculi?
Depends on the cause (e.g. parathyroidectomy if hypercalcaemia due to hyperparathyroidism, allopurinol if hyperuricaemia)
What advice do you give to someone with Urinary Tract Calculi?
Increased oral fluid intake
What are the potential complications of the stones in Urinary Tract Calculi?
Infection (pyelonephritis)
Septicaemia
Urinary retention
What are the potential complications of ureteroscopy for Urinary Tract Calculi?
Perforation
False passage
What are the potential complications of Lithotripsy for Urinary Tract Calculi?
Pain
Haematuria
What is the prognosis for patients with Urinary Tract Calculi?
GOOD
However, infection of the calculus could lead to irreversible renal scarring
Recurrence of about 50% over 5 yrs
