Urinary System Disorders

Incontinence and Retention Loss of voluntary control of bladder Stress incontinence Increase in intra-abdominal pressure Forces urine through sphincter Laughing Coughing Females weakened Spinal cord injuries, brain damage Inability to empty bladder May accomp overflow incontinence Spinal cord injury Inability to control managed by pads, briefs Catheter Tube inserted in urethra Drains urine from bladder to collecting bag Common source of UTI

Diagnostic Tests—Urinalysis Constituents, characteristics of urine vary w/ dietary intake, drugs, care of specimen Normally clear, straw-colored; pH 4.5-8.0 Appearance Cloudy Presence of lg amts protein, blood cells, bacteria, pus Dark color Hematuria (blood), excessive bilirubin, high concentration of urine Unpleasant, unusual odor infection

Diagnostic Tests—Urinalysis Abnormal constituents (high in numbers) Blood (hematuria) Small, microscopic amts Infection, inflammation, tumors of UT Lg # RBC Increased glomerular permeability or hemorrhage in tract Protein (Proteinuria) Leakage of albumin into filtrate Inflammation, increased glomerular permeability Bacteria (Bacteriuria) and Pus (Pyuria) Indicates UTI Urinary casts Microscopic mold of tubules Consists of one or more cells, bacteria, protein Inflammation of tubules Specific gravity Ability of tubules to concentrate urine Low is related to renal failure

Diagnostic Tests—Blood Tests High serum urea and creatinine Indicate failure to excrete N wastes Due to low GFR Metabolic acidosis Indicates low GFR, failure of tubules to control acid/base balance Anemia Indicates low erythropoietin secretion and/or bone marrow depression Due to accumulating wastes Electrolytes Antibody level Antistreptolysin O (ASO) or antistreptokinase (ASK) Renin levels Indicate cause of hypertension

Dialysis Provides “artificial kidney” 2 forms Sustains life after kidney fails Acute renal failure or end-stage renal failure (those waiting for a transplant) 2 forms Hemodialysis Peritoneal dialysis

Disorders of the Urinary System: Urinary Tract Infections (UTI) Very common Urine is excellent medium for microorganismal growth Escherichia coli Most are ascending Perineal cavity  mucosa  bladder  ureters  kidneys

UTI—Etiology Females more anatomically vulnerable Short urethra Proximity to anus Frequent irritation to tissues Tampons, bubble bath, sexual activity Older males with prostatic hypertrophy and retention of urine prone to UTI

UTI: Cystitis—Signs and Symptoms Pain in lower abdomen Dysuria, frequency, urgency Inflammation of bladder wall irritated by urine Systemic signs of infection Cloudy urine with unusual odor Urinalysis indicates bacteria (+100,000/mL), pyuria, microscopic hematuria

UTI: Pyelonephritis—Signs and Symptoms Signs of cystitis Pain Dull aching in lower back Results from renal capsule stretching Urinalysis Similar to cystitis Except urinary cast Leukocytes or renal epithelial cells present Involvement of renal tubules

UTI—Treatment Antibiotics (Bactrim) Increase fluid intake Especially cranberry juice Tannin decreases ability of E. coli to adhere to bladder mucosa Infection reoccurs unless predisposing factors removed

Disorders of the Urinary System: Inflammatory Disorders Glomerulonephritis Many forms Acute Poststreptococcal Glomerulonephritis (APSGN) Follows streptococcal infection Originates as upper resp infection, middle ear infection, strep throat Primarily affects kids 3-7 (especially boys) develops 2 weeks after previous infection

Glomerulonephritis—Signs and Symptoms Back pain Stretching renal capsule Dark, cloudy urine Oliguria Facial edema, then generalized Low osmotic pressure of blood Salt, water retention Generalized signs of inflammation Increased bp

Glomerulonephritis—Diagnostic Tests Blood tests High serum urea and creatinine and decreasing GFR Streptococcal antibodies, ASO, ASK Metabolic acidosis Low serum bicarbonate, low pH Urinalysis Confirms presence of proteinuria, erythrocyte casts

Glomerulonephritis—Treatment Sodium restriction Glucocorticoids Antibiotics Recovery w/ minimal damage Imp to prevent further exposure to streptococcal infection and recurrent inflam Adults more difficult Acute renal failure in 2% Chronic glomerulonephritis in 10% Gradually destroys kidneys Postrecovery testing should be done

Urinary Tract Obstructions: Urolithiasis Also called: Calculi Kidney stones Frequently reoccur if not treated

Calculi—Pathophysiology Can develop anywhere in UT; lg or small Once any solid material or debris forms Tend to form when: excessive amts of relatively insoluble salts are in filtrate Insufficient fluid intake creates highly concentrated filtrate 75% composed of calcium salts Remainder: uric acid, struvite, oxalate Usually cause manifestations only when obstruct flow of urine Infection if stasis of urine

Kidney Stones

Calculi—Signs and Symptoms Stones in kidney/bladder frequently asymptomatic Obstruction of ureter causes attack “renal colic” Consists of intense spasms in back and groin Pain caused by vigorous contractions of ureter Effort to pass the stone

Calculi—Treatment Small stones eventually passed out Larger stones Extracorporeal shock-wave lithotripsy (ESWL) Decreases need for invasive surgery Some drugs can partially dissolve Need to prevent recurrences

Urinary Tract Obstructions: Tumors—Renal Cell Carcinoma Primary, silent tumor Arises from tubule epithelium Asymptomatic in early stage Often metastize to liver, lungs, bones, CNS at time of diagnosis Common after 50 More freq in males and smokers Initial sign is painless hematuria Other manifestations Dull aching flank pain, palpable mass, anemia Treatment is kidney removal 5 yr survival rate 50%