Transcript Kidneys and Urinary Tract

Kidneys and Urinary Tract
Premed 2
Pathophysiology
• The kidneys are paired organs, which
have the production of urine as their
primary function.They are an essential part
of the urinary system, but have several
secondary functions concerned with
homeostatic functions. These include the
regulation of electrolytes, acid-base
balance, and blood pressure.
• In producing urine, the kidneys excrete
wastes such as urea and ammonium; the
kidneys also are responsible for the
reabsorption of glucose and amino acids.
Finally, the kidneys are important in the
production of hormones including calcitriol,
renin and erythropoietin.
• Located behind the abdominal cavity in the
retroperitoneum, the kidneys receive blood
from the paired renal arteries, and drain
into the paired renal veins. Each kidney
excretes urine into a ureter, itself a paired
structure that empties into the urinary
bladder.
Endocrine Function
• The kidneys secrete the following
hormones to initiate processes that occur
in other parts of the body:
• 1. Erythropoietin
• 2. The active form of Vitamin D, 1,25dihydroxyvitamin D3,
• 3. Renin
Urinary tract Infection
• More common in women, pregnancy
• Most common organism: Escherichia coli
• Predisposing factors:
obstruction
surgery
catheters
gyne abnormalities
• Urinary frequency
• Dysuria, pyuria, hematuria, bacteriuria
UTI
• Acute cystitis
pyuria
hematuria
no white cell casts
• Acute pyelonephritis
fever, flank pains
white cell casts
Urolithiasis
• Calculi or stones in the urinary tract; men
• Most common type:
calcium stones
calcium oxalate, calcium phosphate
radiopaque
• Hypercalcemia, hypercalciuria
• Causes: hyperparathyroidism
malignancy
vitamin D intoxication
Urolithiasis
• MAP stones: magnesium ammonium
phosphate
• Second most common type
• Radioluscent
• Staghorn (struvite) calculi
• Infections with Proteus and
Staphylococcus
Urolithiasis
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Uric acid stones
hyperuricemia
gout
leukemia
myeloproliferative diseases
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Cystine stones
cystinuria
Adult polycystic disease
• Most common inherited disease of the
kidney
• Shows clinically at 15 to 30 years old
• Large kidneys, bilateral
• Numerous cysts in the parenchyma
• Associated with berry aneurysms in the
circle of willis
Renal Failure
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May be acute or chronic
Always presents with azotemia
Late stages: uremia
Others: acidosis
hyperkalemia
abnormal fluid control
hypocalcemia
anemia
hypertension
Glomerulus
Glomerular diseases
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Nephrotic syndrome
Proteinuria
Hypoalbuminemia
Edema
Hyperlipidemia,
hypercholesterolemia
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Nephritic syndrome
Oliguria
Azotemia
Hematuria
Hypertension
Glomerular diseases
• Minimal change
disease
• Focal segmental
glomerulosclerosis
• Membranous
glomerulonephritis
• Lupus nephropathy
• Poststreptococcal
glomerulonephritis
• Rapidly progressive
glomerulonephritis
• Goodpasture
syndrome
• Alport syndrome
Minimal change disease(lipoid
nephrosis)
• common in young
children
• fused or absent
epithelial foot
processes
Membranous glomerulonephritis
• primary cause of
nephrotic syndrome
• teens, young adults
• Diffuse thickening of
the glomerular
capillary wall
• immune complexes
deposits
• “spike and dome”
appearance
Nephrotic syndrome
• Lupus nephropathy
immune complexes :
• “ wire loops”
Nephritic syndrome: Poststreptococcal glomerulonephritis
-immune complex
deposits : “lumpybumpy”
-follows/accompanies
infection: group A
beta-hemolytic
streptococci
-increased ASO titers
ALPORT SYNDROME
Is hereditary nephritis.
• abnormal collagen
(type IV)
• deafness,various eye
disorders, lens
dislocation, cataracts,
corneal dystrophy.
Rapidly progressive
glomerulonepritis
• Renal failure in weeks
• Fibrin deposits in the
Bowmans
spacecrescents
• Caused by:
poststreptococcal –
50%
Goodpasture syndrome
• antibodies against the
glomerular membrane
• Linear pattern
• hemoptysis