Urolithiasis is the formation of urinary stones in the kidney, bladder and/or urethra.

The hallmark of obstruction in the ureter and renal pelvis is the sudden onset of excruciating, intermittent pain that radiates from the flank to the groin or to the genital area and inner thigh.

It is a painful urologic disorder that occurs in 12% of the global population and has a high recurrence rate among male patients.

Lower urinary tract symptoms that are associated with urolithiasis are urgency, frequency, urge incontinence and dysuria.


Surgical Intervention

Indications for active removal of stones:

  • Choice of treatment or patient preference
  • Comorbidity (eg hypertension, diabetes, obesity, dyslipidemia & gout)
  • Infection (eg pyelonephritis)
  • Obstruction caused by stones
  • Patients who are high-risk stone formers
  • Stone size of ≥6 mm after a period of watchful waiting
  • Symptomatic stones (eg presence of pain & hematuria)

Special problems encountered in stone removal:

  • Presence of caliceal diverticulum stones
  • Patient has horseshoe kidneys
  • Patients w/ uteropelvic junction (UPJ) obstruction

Extracorporeal Shockwave Lithotripsy (SWL)

  • A noninvasive & non aesthetic procedure, & the first choice of treatment for stone <1.5cm
  • Success depends on the efficacy of the lithotriper & some factors:
    • Size, composition & location of the stones
    • Patient’s habitus
    • Performance of extracorporeal shockwave lithotripsy (SWL)
  • Contraindications include:
    • Arterial aneurysms
    • Anatomical destruction distal to the stones
    • Bleeding diathesis
    • Infection
    • Severe skeletal malformations
    • Severe obesity
    • Uncontrolled urinary tract infections (UTIs)

Percutaneous Nephrolithotomy (PNL)  

  • Standard procedure for large renal calculi
  • Different rigid & flexible endoscopes are used in this procedure & it depends on the preference of the surgeon
  • Contraindications include:
    • Patients on anticoagulant therapy
    • Untreated UTI
    • Tumor in the presumptive access tract area
    • Potential malignant kidney tumor
    • Pregnancy
  • Complications associated w/ PNL:
    • Fever
    • Bleeding
    • Urinary leakage
    • Problems due to residual stones
    • Steinstrasse
      • Accumulation of stone fragments or stone gravel in the ureters
      • Major factor for its formation is the size of the stone
      • If asymptomatic, then conservative treatment is the initial option
      • For steinstrasse associated w/ UTI & fever, percutaneous nephrostomy is indicated
      • When large stones fragments are present, shockwave lithotripsy is indicated

Uteroscopic Lithotripsy - Rigid & Flexible (URS)

  • A minimally invasive procedure that is used for both ureteric & renal stones as an alternative treatment to extracorporeal shockwave lithotripsy (SWL)
  • Can be performed under a local, intravenous or general anesthesia
  • URS may be used in patients who had failed previous treatment attempts, stones too large for SWL, strictures, tumors, stones in children, those w/ bleeding disorders & obese
  • Stone-free rate status w/ larger stones is achieved earlier w/ URS
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