Lecture on Renal and Urine System

Objectives

• Impact of renal function on blood pressure
• Evaluate presentation of CKD, AKI, neurogenic, PCI, and reduction in odor-active blood

Anatomy of the Renal System

• Components: Kidneys, ureters, renal pelvis, bladder
• Location: Kidneys located between 12th thoracic and 3rd lumbar vertebrae
  • Right kidney slightly lower than left

Nephron: Functional Unit of Kidney

• Role: Concentration and dilution of fluids
• Components:
  • Renal corpuscle
  • Proximal convoluted tubule
  • Loop of Henle
  • Distal convoluted tubule
  • Collecting ducts
• Types:
  • Cortical nephron
  • Juxtamedullary nephron

Kidney Functions

• Glomerulus:
  • Afferent arterioles deliver blood
  • Efferent arterioles carry blood away
  • Blood filtration and regulation
• Peritubular Capillaries:
  • Surround renal tubules and aid in reabsorption
  • Located in cortex and medulla

Renal Blood Flow

• Blood Flow Volume: 1,000 to 1,200 mL/min
• Cardiac Output: 20-25% filtered through kidneys
• Glomerular Filtration Rate (GFR): Rate of plasma filtration through the glomerulus

Regulation of Blood Pressure and Renal Blood Flow

• Auto-Regulation: Keeps GFR constant despite changes in blood pressure
  • System pressures between 80-180 mmHg maintain constant GFR
• Tubuloglomerular Feedback: Adjusts blood flow via sodium concentration detection

Hormonal Regulation

• Renin: Responds to low blood pressure, promotes vasoconstriction
• Antidiuretic Hormone (ADH): Concentrates urine
• Aldosterone: Increases sodium reabsorption, affects blood pressure

Kidney Diseases and Disorders

Urinary Tract Obstruction

• Types: Complete or partial; structural or functional
• Effects:
  • Dilation and risk of infection
  • Affects tubular and glomerular function
  • Can lead to scarring and tubular damage

Nephrolithiasis (Kidney Stones)

• Risk Factors: Age, sex, race, dietary intake, medical history
• Types: Calcium oxalate, phosphate, struvite, uric acid

Urinary Tract Infections (UTI)

• Types: Cystitis, acute pyelonephritis
• Common Organism: E. coli
• Symptoms: Pain, pressure in pelvic region

Acute Kidney Injury (AKI)

• Causes: Hypoperfusion, toxic injury
• Classification:
  • Pre-renal: Reduced blood flow
  • Intrarenal: Tubular necrosis
  • Post-renal: Obstruction

Chronic Kidney Disease (CKD)

• Stages:
  • Stage 1: GFR > 90, no symptoms
  • Stage 2: Mild damage, GFR 60-89
  • Stage 3: Moderate damage, GFR 30-59
  • Stage 4: Severe damage, GFR 15-29
  • Stage 5: End-stage renal disease, GFR < 15
• Effects: Affects multiple body systems; cardiovascular, bone metabolism, immune system

Discussion on GFR and Racial Differences

• Current practices may still show racial differences in GFR calculations
• Recent changes in transplant eligibility criteria to remove racial bias

Summary

• Kidney Function: Urine production, blood pressure regulation, electrolyte balance
• Disease Impact: Can lead to comprehensive systemic effects if not managed properly
• Effective early diagnosis and treatment crucial for urinary obstructions and renal diseases