Urinary System
Review of Structure and Function
Age Related Changes
Kidneys thickening of capsule, decrease cortical mass decrease renal blood flow (RBF) decrease # of glomeruli GFR decreases 50% by age 80 general atrophy, dec. mass 30% by age 80 altered permeability of glomeruli proteinuria loss of tubules decreased ability to concentrate urine decreased ability to regulate pH loss of reserve capacity
Age Related Changes
Bladder and Urethra loss of muscle, elasticity of bladder wall less able to expand (stretch) and contract decreased max. volume increased residual volume inc. risk of bladder infections more frequent urination nocturia- 3 or more X/night
Age Related Dysfunction
Urinary Incontinence involuntary passage of urine 30% of all people over 65 suffer some degree weakening of the bladder sphincters loss of control of external sphincter muscle weakening in muscles in the pelvic floor (post-menopausal women)
Age Related Dysfunction
Problems Caused by Prostate Benign hyperplasia enlarges, compressing urethra decline in urine flow rate can impede flow
Adenocarcinoma of the prostate 50% of men over 70 !! Slow growing, only 1/3 become clinically significant urethral obstruction palpation, PSA test
Age Related Dysfunction
Renal Calculi Kidney Stones most common in middle-aged men may obstruct urine flow Calcium oxalates - electron dense Urate salts - not visible on X-ray Risk Factors: hyperparathyroidism diet dehydration gout