This is renal pathophysiology !

Dr. Suparyanto, Kes
RENAL PATHOPHYSIOLOGY
RENAL FUNCTION

    Vital organs of the body maintain a stable internal environment (ECF)
    The kidneys regulate the balance: body fluids, electrolytes, acid base balance by blood filtration
    Selective reabsorption of water, electrolytes and non electrolytes
    Mengekresikan excess water, electrolytes, acid-base as the urine


    The kidneys also function to excrete metabolic waste (urea, and uric acid kreatinine), metabolites (hormones) and foreign chemicals (drugs)
Kidney secreting (endocrine function):

    Renin (important for the regulation of blood pressure)
    1.25 dihydroxy vitamin D3 (essential to regulate calcium)
    Erythropoietin (essential for the synthesis of erythrocytes)

MECHANISM RENIN - angiotensin - aldosterone

    The mechanisms responsible for maintaining blood pressure and tissue perfusion by regulating ion homeostasis Na
    Hypovolemia, hypotension and renal hypoperfusion → → ↓ perfusion pressure in the afferent arteriole and ↓ delivery of NaCl to the macula densa → renin secretion from both causes JG cells (Juksta glomerulus or Granular cell) on the wall of afferent arteriole


    Renin in the circulation led to the outbreak of the substrate angiotensinogen (liver produced) → Angiotensin 1
    Angiotensin 1 → converted into angiotensin 2 by ACE (Angiotensin Enzyme Converted) generated Lung and Kidney
    Angiotensin 2 → have 2 effects:

    Arteriole vasoconstriction and
    ↑ Pe Na ion reabsorption of water and the blood pressure rises →

CHART MECHANISM RENIN-angiotensin-aldosterone


ADH MECHANISM

    ADH mechanism plays an important role in the regulation of water metabolism and maintain normal blood osmolality → by stimulating thirst and regulate water excretion through the kidneys and urine osmolality
    ECF volume and pe ↓ ↑ → osmoraritas ECF stimulates the secretion of ADH (posterior pituitary)


    ADH → blood flow to the renal medulla medulla interstitial hypertonicity ↓ → ↑ → ↑ → urine concentrating ability of urine ↓
    ADH → duct permeability to water koligen urine concentration ↑ → ↑ → ↓ urine

Renal BLOOD FLOW

    RBF or renal blood flow is 1000 - 1200 ml / min or 20-25% of cardiac output
    RPF or renal plasma flow of about 660 ml / min
    GFR (glomerulus Filtration Rate) → index of kidney function = 125 ml / min in men and 115 ml / min (women)
    GFR will decrease after the age of 30 years 1ml/menit/tahun

KIDNEY DISEASE DIAGNOSTIC PROCEDURES
Biochemical methods:

    Chemical Examination of Urine
    Glomerular filtration rate
    Tubules function tests

Morphologic methods:

    Examination of Urine Microscopy
    Urine bacteriological examination
    Radiological examination
    Kidney biopsy

Proteinuria

    Normal protein excretion in the urine of less than 150 mg / day if more Pathological →
Causes Proteinuria:

    Functional
    Outflows (pre-renal)
    Glomerular
    Tubules


    Functional proteinuria (temporary) → found in normal kidneys case, due to excessive protein excretion pd case: fever, weight training, due to the standing position (orthostatic proteinuria)
    Pre-renal proteinuria: the excretion of protein due to low BM (excess protein production) in the case of Multiple Myeloma → → where the amount of filtered protein that exceeds the capabilities of the tubular reabsorption


    → persistent proteinuria found in systemic and renal disease
    Proteinuria increased permeability glomelural glomelural is due to the loss amount or size of the glomerular barrier (layer of the glomerulus: endothelial, epithelial and basement membrane) → protein that can qualify with a low BM


    Tubulointerstisial disease can interfere with absorption of proteins that lead to tubular proteinuria (chronic pyelonephritis, renal tubular acidosis, Fanconi syndrome, Acute tubules necrosis (ATN))
    → neprotik syndrome protein loss of 3.5 g / hr or more in the urine

Hematuria

    Hematuria blood in urine →
    Hematuria is often a sign of kidney disease (glumerulonefritis) or lower urinary tract disease (infection, stones, trauma, and neoplasms)

KIDNEY STONES

    Most common types of kidney stones: calcium oxalate, calcium phosphate or a mixture
    Which stimulates the formation of stone: static urine, persistent infection or the use of catheters
    Uric acid stones form in acidic urine and obstructive uropathy due to the crystallization of uric acid
    Prevention of stone formation: drink plenty of water

WEIGHT OF URINE

    → urine specific gravity measurements used to estimate the urine osmolality
    BJ 1.010 → berhub with normal blood osmolilitas
    BJ min of diluted urine: 1.001
    BJ urine goo max: 1.040
    At first → progressive renal failure, the kidneys lose the ability to concentrate urine and to lose the ability → → BJ urine dilute urine to survive 1.010 at the moment of end-stage renal failure

GFR

    GFR → The most important index of kidney function and clinically measured by creatinine clearance test
    Levels of serum creatinine (normal: 0.7 to 1.5 mg / dl) and BUN (normal: 10-20 mg / dl) is inversely proportional to GFR and can be used for the assessment of failure and renal insufficiency crisis
    BUN (Blood Urea Nitrogen) is less accurate than creatinine → due to intake of protein in the diet and state of catabolism may affect the BUN

TEST tubular function

    Tubular function is: selective reabsorption and secretion of tubular fluid into the tubule lumen
Test the proximal tubular function:

    Excretion tests fenolsulfonftalein
    The Amino Hipurat (PAH)
Distal tubular function tests:

    Test concentration, dilution, acidification and conservation of Na

URINE Sediment

    Abnormal urine elements: erythrocytes, leukocytes, bacteria, cylinder (the protein that forms in the tubules and ducts koligen)
    Cylinders are named based on the inherent cellular elements (erythrocytes, leukocytes, bacteria, cell tubules)
    Cylinder which had a high diagnostic value because it comes from the kidneys
    Width → cylinder reply granular kidney failure
    → bacteriuria> 105 CFU / ml (Colony Form Unit)

Ultrasound

    Ultrasound → gives info about size and anatomy of the kidney, including cysts and dilatation of the Kalix
    → Doppler ultrasound to assess flow in the renal artery and vein
    CT scan and MRI (Magnetic Resonance Image) → describe the renal system

Radiography

    Plain radiographs and kidney stones → size radioopak
    IV contrast (IVP) → outline of the kidneys and urinary tract
    Dx → Sistouretrogram without reflux of contrast vesikuloureteral
    Renal angiography → contrasts radioopak through a catheter. Femoral

Biopsy

    Diagnosis requires renal biopsy histology →
    Percutaneous needle biopsy is done by cutting through the back with the help of ultrasonic

REFERENCES

    Price, Wilson (2005), Pathophysiology, Clinical Concepts Disease Processes, London: EGC, issue 6
Posted by dr. Suparyanto, Kes at 20:59