Renal failure

• Renal Failure


  Reduced clearance of certain solutes principally excreted by the kidney
• Renal Failure


  • The most common indicators are urea & creatinine
  • Could be acute (reversible) or chronic (irreversible)
  • ESRD: CRF with GFR <15ml/kg/min → not live without renal replacement therapy (dialysis or transplantation)

  
• Causes of end stage renal failure

  • DM (36%)
  • Hypertensive nephrosclerosis (30%)
  • Chronic glomerulonephritis (24%)
  • Autosomal dominant polycystic kidney disease (12%)
  • Chronic pyelonephritis

  
• In pediatric age group (<18 year) congenital causes predominate like cong. hypoplasia, VUR
• Treatment of end stage CRF


  • Hemodialysis
  • Peritoneal dialysis
  • Renal transplantation

  
• Renal Transplantation


  The treatment of choice & the most cost effective treatment for end stage renal failure

  
• Upper age limit for renal transplantation

  • 70 year of age in average
• Types of donors for renal transplantation


  • Living related donors
  • Living unrelated donors
  • Cadaveric donors
• Living related donors


  • Allograft half life is 10 year longer than cadaveric renal donation
• Recipient evaluation


  • Cardiac status
  • Malignant diseases
  • Infections
  • GIT diseases like peptic ulcer
  • GU abnormalities: MCUG, URODYNAMIC STUDY
• Pretransplant bilateral native kidney nephrectomy is seldom required

  
• Indications for pretransplant bilateral native kidney nephrectomy


  • Pyelonephritis
  • Medically uncontrolled renin mediated hypertension
  • Malignant disease
  • Nephrotic syndrome
  • Extremely large polycystic kidney

  
• Contraindications for renal transplantation


  • Active infections including AIDS
  • Active malignant diseases

  
• The donor is always left with the better kidney
• Left kidney is preferred due to longer renal vein
• Investigations & HLA tissue matching


  • Tissue matching for HLA-A,B,&DR antigen
  • ABO blood grouping & cross matching
• Technical complications of renal transplantation


  • Renal artery stenosis
  • Vascular anastamotic leak
  • Ureteral stricture
  • Ureteral obstruction
  • Ureterovesical disruption
  • Lymphocele

  
• Non-technical complications of renal transplantation


  • Rejection of graft
  • Infections
  • Cancers: lymphoma, Kaposi sarcoma

  
• Types of rejections


  • Hyperacute rejection
  • Acute rejection
  • Chronic rejection
• Hyperacute rejection


  Incidence 1/1000, analogous to blood transfusion reaction, occurs immediately, preformed Ab against HLA expressed on donor renal vascular endothlium, occurs as soon as blood flow to the donor kidney is established, treatment: immediate transplant removal

  
• Acute rejection


  Occurs between 1st week- 1 month, occurs in 25 – 55% of patient, Differential diagnosis: ATN, ureteral obst, drugs toxicity, Clinically: febrile, tenderness over the graft, impaired renal function, decrease urine output, Diagnosis: renal biopsy, treatment: by steroids & immunosuppressants
• Chronic rejection


  Defined as a gradual progressive loss of renal function that cannot be attributed to another cause, there is no definitive treatment, retransplantation to be considered

  
• Immunosuppression


  • Induction: immediately after Tx like steroids & Azathioprine
  • Maintenance: initiated once creatinine in normalised like Azathioprine (imuran), cyclosporin-A (sandimmune), mycophenolate mofetil (cellcept)
  • Treatment of acute rejection: like high dose steroids