(O&G)

Overview

• Nephrolithiasis → presence of crystalline stones (calculi) within the urinary system (kidneys and ureter)
• M>F (3:1), peak incidence 45-70 yrs old
• Risk Factors → dehydration, high salt intake, white ancestry, male, obesity, crystalluria
• Types of Stones → calcium oxalate (most common, 75%), struvite (15%) uric acid (5%), cysteine (1%)
  • Calcium Oxalate ⇒ radioopaque (white on x-ray/CT), acidifies urine pH, hypercalciuria is a risk factor
  • Struvite ⇒ radioopaque, tend to form staghorn calculi, alkalizes urine pH, UTI with urease producing bacteria. Recurrent UTIs are predisposing factor (chronic proteus infection). Made up of magnesium ammonium phosphate.
  • Uric Acid ⇒ radiolucent (black on x-ray/CT - not visible on x-ray), associated with gout/hyperuricaemia.

Making Diagnosis

Clinical Features:

Asymptomatic until calculi gets stuck.

• Renal Colic → severe, acute flank pain that radiates to the groin (loin → groin pain)
  • May be colicky
• Nausea & Vomiting
• Urinary frequency / urgency
• Haematuria (85% microscopic)
• Testicular pain

Investigations: