Renal Calculi
Epidemiology
· M>F; 3:1
Risk factors
Clinical Features
Symptoms
NOTE: Important DDx is leaking AAA in men, ectopic pregnancy in women
Signs
· Distressed, writhing while trying to find comfortable position (versus acute abdomen – board like rigidity/do not want to move)
· ± Abdominal tenderness: costovertebral angle or lower quadrant tenderness
Investigations
Management
DDx (AUA)
- NOTE: Important DDx is leaking AAA in men, ectopic pregnancy in women
- Renal or ureteric stones
- Hydronephrosis (uretopelvic junction obstruction, sloughed papilla)
- Bacterial cystitis (esp if stone approach uretovesical junction); or pyelonephritis
- Acute abdomen causes (bowel, biliary, pancreatic, AAA sources)
- Gynaecological (ectopic, ovarian cyst torsion/rupture)
- Referred pain (orchitis)
Source
Dr Kathryn Gilliams 2014
On call (Marshall & Ruedy) 2013
American Urology Association 2014 http://www.auanet.org/education/kidney-stones.cfm
· M>F; 3:1
Risk factors
- Abnormal anatomy
- Stasis (BPH)
- Infection
- FHx/ PMHx – 55% of pt with recurrent stones have FHx
- Gout
- HyperPTH
- Ca2+/ Vit D supplements
Clinical Features
Symptoms
- Can be asymptomatic
- Abdo pain: acute, colicky, severe, radiating, loin-to-groin/scrotum pain; or just lower quadrant pain (if stone near uretovesical junction)
- Haematuria
- Frequency, urgency, dysuria ("FUD")
- Nausea & vomiting
- Fever
NOTE: Important DDx is leaking AAA in men, ectopic pregnancy in women
Signs
· Distressed, writhing while trying to find comfortable position (versus acute abdomen – board like rigidity/do not want to move)
· ± Abdominal tenderness: costovertebral angle or lower quadrant tenderness
Investigations
- Urine dipstick, & MSU for M/C/S – gross or microscopic haematuria (90% of patients)
- Absence of haematuria + acute flank pain does not preclude renal or ureteric calculi – ∵ complete obstruction
- FBC, UEC (?renal deterioration → urgent intervention)
- Non-contrast CT KUB (abdomen/pelvis) (can detect AAA) – gold standard
- If CT not available: plain abdominal radiograph (KUB) ∵ 75-90% stones are radio-opaque; may be used for "baseline" monitoring
- In pregnant women, ultrasound first for urinary calculus (although insensitive for ureteric calculi)
Management
- Refer to urology
- Urgent referral if urosepsis + stone disease; obstructed upper tract + infection; impending renal deterioration; pain refractory to analgesia; intractable N&V
- Assess likelihood of spontaneous stone passage (size and location) – 80% stone will pass without complication (within 4 weeks of onset of sx). <5mm more likely; in ureter less likely.
- Medical therapy:
- IV fluids for hydration
- NBM if considering surgery
- Analgesia, anti-emetics
- Morphine 0.1mg/kg IV; Metoclopramide 10mg IV
- Then, if no active PUD/renal impairment/asthma – indomethacin 100mg PR (rectum) or PO NSAID
- Strain urine for stones – if think will pass; check pH of urine
- CCB, alpha blockers (e.g. tamsulosin; relax mm) – medical expulsion therapy
- Thiazides for Ca2+ stones, allopurinol for uric acid stones, Ca citrate for oxalate stones
- ?IV antibiotics
- Surgical therapy (if stone not passed in few days, or recurring pain, or obstruction with hydronephrosis)
- Lithotripsy
- Ureteroscope + Basket extraction + Stent (ureteric stent/catheter)
- Ureteroscope + Laser
- Nephrolithotomy (PCNL)
- Open surgery (rare)
DDx (AUA)
- NOTE: Important DDx is leaking AAA in men, ectopic pregnancy in women
- Renal or ureteric stones
- Hydronephrosis (uretopelvic junction obstruction, sloughed papilla)
- Bacterial cystitis (esp if stone approach uretovesical junction); or pyelonephritis
- Acute abdomen causes (bowel, biliary, pancreatic, AAA sources)
- Gynaecological (ectopic, ovarian cyst torsion/rupture)
- Referred pain (orchitis)
Source
Dr Kathryn Gilliams 2014
On call (Marshall & Ruedy) 2013
American Urology Association 2014 http://www.auanet.org/education/kidney-stones.cfm