1. Disorders of glomerular filtration

Transcription

1 RENAL DISEASES 1. Disorders of glomerular filtration 2. Nephrotic syndrome 3. Disorders of tubular transport 4. Oliguria and polyuria 5. Nephrolithiasis 6. Disturbances of renal blood flow 7. Acute renal failure 8. Chronic renal failure 9. Testing of renal function

2 1. Disorders of glomerular filtration 1) Disorders of glomerular filtration rate 2) Disorders of filtrate composition Acute x Chronic Disorders of glomerular filtration rate Decrease of GFR Causes: lower filtration pressure (hydrostatic pressure) smaller filtration area (number of glomeruli) low permeability of glomerular membrane Consequences: retention, H+ excretion, hyperkalemia Increase of GFR Causes: high filtration pressure (hydrostatic pressure, oncotic pressure) Consequences: loading of tubuli, interstitial osmotic gradient, glomerular damage Composition of filtrate Increased permeability of glomerular membrane Electrical charge Size of filtrated molecules Tests: azotemia, kreatinin, clearance, proteinuria, hematuria

3 2. Nephrotic syndrome Abnormal permeability of glomeruli Idiopathic (primary) x secondary Consequences: Nephrotic proteinuria (selective, nonselective) los of more than 3g of protein per day (tubular and glomerular theory) Hypoproteinemia Hypalbuminemia (less than 25g/L) Hyperlipidemia (hypercholesterolemia, hypertriglyceridemia) Edema (underfill and overflow theories, typical localization, complications) Complications: Thrombotic diathesis Infection Atherosclerosis Chronic renal failure Therapy: Corticoids (sensitivity, side effects) Albumin Diuretics ACE-inhibitors

4 3. Disorders of tubular transport Inherited - typically one or few substances Renal glycosuria Renal tubular acidosis Renal diabetes insipidus Acquired - complex disturbance of function Inflammation Ischemia Toxins Acute Acute tubular necrosis - acute renal failure, anuria Acute tubulointerstitial nephritis - acute renal failure, oligouria Chronic Tubulointerstitial nephropathies Proximal nephron dysfunction Distal nephron dysfunction Signs: AB balance disorders Disorders of ability to concentrate (dilute) urine Losses Tests of tubular function: Urine Tubular maximum (Tm) Clearance (osmolar and free water clearance)

5 4. Oliguria and polyuria Oliguria: daily < 400 (500) ml urine Polyuria: > 3-5 L Oliguria Decreased GFR Increased reabsorption Polyuria Increased GFR Disorders of countercurrent multiplier Osmotic Disorders of distal tubule and collecting duct Pollakisuria

6 5. Nephrolithiasis Stones formation: 1) high concentration of lithogenic substances 2) decreased lithogenic protection 3) nucleus Urolithiasis: nephrolithiasis, ureterolithiasis, cystolithiasis, urethrolithiasis Consequences: Obstruction of urinary ways Infection (sepsis) Pain, injury and formation of scars Hydronephrosis Postrenal type of renal failure Signs: None, hematuria (microscopic or macroscopic), infection Renal colic (characteristic, propagation) Metabolic disorders (hypercalciuria, hyperoxaluria, cystinuria, hypocitrateuria) Diagnosis Therapy

7 6. Disturbances of renal blood flow Functional and nutritional flow Clearance of PAH Causes of a decrease in blood flow: Prerenal - low BP Renovascular - high resistance in a. renalis Renal - high resistance in renal parenchyma Postrenal - venous outflow Consequences: Low GFR RAAS activation Ischemia (proximal tubuli) High blood flow Consequences: High GFR Damage of vessel wall Glomerular endotheluim, increase permeability, filtration of large molecules Sclerotization Increased tubular load

8 7. Acute renal failure Classification: prerenal renal postrenal Oliguric (anuric) phase Polyuric phase Retention: H + and K + - consequences, heart rate water and other ions - hypervolemia organic substances - azotemia Transition between oliguric and polyuric phase: GFR and excretion of retained substances, failure of tubular reabsorption Dialysis Hemodialysis x peritoneal dialysis (principle, difference in effectiveness of concentration and pressure gradients, advantages, disadvantages) Principle of hemodialysis

9 8. Chronic renal failure Classification: prerenal (hypertension) renal (chronic glomerulonefritis, diabetes mellitus, interstitial inflammation) postrenal Restriction of filtration area combined with hypertension and tubular dysfunction: Combination of retention and losses Water and electrolytes Azotemia Hypertension Hyperphosphatemia, hypocalcemia, secondary hypeparathyreoidism, vit. D Anemia Immune dysfunction Neuropathies Uremic sy, coma Nephrotic sy - proteinuria, hypalbuminemia, edema, hyperlipidemia Hepatorenal sy splanchnic vasodilation, renal vasoconstriction Cardiorenal sy - treatment of congestive heart failure is limited by decline in kidney function Dialysis Hemodialysis x peritoneal dialysis (principle, difference in effectiveness of concentration and pressure gradients, advantages, disadvantages) Principle of peritoneal dialysis

10 9. Testing of renal function Urine: ph Sediment (cells, crystals, casts, others) erytrocyturia (phase contrast) epithelial cells cylindres Proteins (selective, nonselective proteinuria) Osmolarity Glomerular function: Clearance of inulin creatinin Estimated glomerular filtration egfr (serum creatinine, age, sex, body weight)

11 Tubular function: Tubular reabsorption Excretion Clearance of osmotically active substances Clearance of water Concentration test (Adiuretin test) ph Clearance of glucose Maximal tubular transport Clearance PAH Sonography Urography Cystometrography Cystometrogram