Urolithiases Flashcards
What is the lifetime risk of having urolithiasis
10-15%
Is urolithiasis more common in males or females?
Males
What is the most common age for urolithiasis to occur?
30-50yrs
What is the lifetime risk of recurrence of urolithiasis?
> 50%
Why do patients get urinary stones?
Anatomical factors
- congenital (horseshoe kidney, duplex, spina bfida)
- acquired (obstruction, trauma, reflux)
Urinary factors are the most common cause
- metastable urine (too much solute in urine), promoters and inhibitors (citrates)
- dehydration is the most common cause of solutes increasing
Infection
- UTI’s causing struvite stones
Mechanism of stone formation?
What are the majority of stones made of?
Nucleation theory - stones form crystals in supersaturated urine
65% are calcium oxalate stones.
How can we prevent stones?
- Overhydration
- Low salt, moderate protein and normal dairy intake
- Reduce BMI
- Active lifestyle
- Remember to check calcium (?PTH)
Preventing uric acid stones
- these only form in acidic urine so deacidifying urine to oH 7-7.5 is preventative
Preventing cystine stones
- Excessive overhydration
- urine alkalinasation
- cysteine binders
- genetic counselling
Symptoms of urinary stones?
- can be asymptomatic
- loin pain
- renal colic
- UTI symptoms - dysuria, strangury, urgency, frequency
- Recurrent UTIs
- Haematuria - majority are non visible haematuria
What is renal colic? What are the associated symptoms and how might a patient present?
- Unilateral loin pain associated with renal stones
- Rapid onset, sharp, searing, burning pain
- Unable to get comfortable - writhing or restless
- Radiates to groin and ipsilateral testis or labia
- Associated nausea or vomiting
- Spasmodic or colicky worse with fluid loading
- Classically severe ‘worse than labour’
What investigations would we consider for ureteric colic?
- ABC exam and give analgesia and anti-emetic
- Focused history and examination
- Urinalysis, MSU if positive
- FBC, U&E, calcium, uric acid
- Imaging - NCCT-KUB, KUBSR, USS
What are some differential diagnosis for renal colic?
- Vascular accident - AAA until proven otherwise
- Bowel pathology - diverticulitis, appendicitis
- Gynae - ectopic pregnancy, ovarian torsion
- Testicular torsion
- Musculoskeletal
What investigation is used for investigating renal colic/stones? Benefits & drawback of using this method?
NCCT-KUB
- very rapid (done in one breath)
- 99% sensitivity for stones
- no contrast used
- does not give information on how the kidneys are functioning
When might we consider using an USS instead of NCCT-KUB for stones?
Pregnant women and children.
How do we manage ureteric colic?
Analgesia - NSAIDs (diclofenac suppository, IV paracetamol)
Anti-emetics - consider admitting to hospital if pain is un-remitted or new AKI or single kidney patient.
Observe for SEPSIS
Why do we worry about sepsis in ureteric colic/stones? How do we manage?
- Can lose renal function in 24h
- Systemic sepsis leading to septic shock
Management
- IV antibiotics, IVI, oxygen, escalate
- Drainage
- Infection in obstructed kidneys can kill and very quickly
