RENAL DISEASE: RENAL STONES AND UT OBSTRUCTION Pathophysiology of Disease: Chapter 16 (401-404)

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RENAL DISEASE RENAL STONES AND UT OBSTRUCTION
Pathophysiology of Disease Chapter 16 (401-404)

• Jack DeRuiter, PhD
• Dept of Pharmacal Sciences
• April, 2000

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Urinary Tract ObstructionCommon Causes (page
402)

• Obstructions of Ureter, Bladder Outlet or Urethra
  caused by
• Structural malformations (Table 16-16)
• Inflammation and Trauma
• Tumor/Cancer of renal and neighboring structures
• Blood clots
• Pregnancy
• Neuropathy/Spinal Cord Disease
• Renal stones

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Clinical Presentation (pages 401-404)

• Flank Pain (/-)
• Distention of ureter, renal pelvis or capsule
• Severity proportional to distention
• Hematuria
• Azotemia Bilateral Obstruction
• Decreased urine production
• Anuria Bilateral obstruction

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Etiology (page 402)

• Hypercalciuria (75) Calcium oxalate stone
• Heredity (Idiopathic most common), Neoplasm,
  Bowel surgery
• Struvite Stones (10-15) Magnesium, Ammonium,
  Phosphate
• UT Infections Urease-Producing microbes
  (Proteus)
• Hyperusicosuria (5-8) Uric acid stones
• Gout, Heredity, Malignancy, Lesch-Nyhan Syndrome
• Cystinuria (1) Defective amino acid transport

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Pathology and Pathogenesis (page 402)

• Cause Nucleation and precipitation of salts in
  renal structures
• Contributing Factors
• Dehydration Less salt dissolved
• High protein diets Acidosis and Inc GFR Ca
• High sodium diet Calcium oxalate
• Essential Hypertension Hypercalciuria
• Dietary calcium and oxalate does not enhance
  likelihood of stone formation in most patients

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Preventative/Protective Measures (page 402)

• Fluids Enhanced dissolution of salts
• Citrate chelates Ca to form soluble complex
  which is excreted
• Magnesium Salt replacement?
• Dietary fiber Indirect Effect?

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Treatment and ComplicationsPages 403-404

• Stone passage Fluids, bed rest and analgesia
• Treatments (Table 16-17)
• Diuretics, urine alkalinization, allopurinol, etc
• Complications
• Hydronephrosis/Complete obstruction
• Infection or abscess behind obstruction
• Renal damage due to repeated stone formation
• Hypertension increased renin production