urinary system

Homeostasis

• Process for maintaining a constant internal environment

  • Maintaining proper balance of water, electrolytes, and acids in the body

  • Constantly filtering the blood to remove urea, creatinine, uric acid, and other waste

  • Converting waste products and excess fluids into urine in the kidneys

Adrenal glands

• Part of the endocrine system

• Located on the top of the kidneys

Genitourinary tract

• Reference to two body systems: urinary tract and reproductive organs

• Located in close proximity

The Kidneys

• Constantly filter blood to remove waste products and excess water

  • Excreted as urine: 95% water and 5% urea and other body wastes

  • Roughly 150–200 quarts of blood processed daily; produces 1–2 quarts of urine

  • Bean-shaped; located in the retroperitoneal space

Renal cortex

Outer region of the kidney; contains nephrons

Medulla

Inner region of the kidney; contains most urine-collecting tubules

Nephrons

• Microscopic functional units of kidneys

• Produce urine

The Renal Pelvis

• Funnel-shaped area inside each kidney 

• Surrounded by the renal cortex and medulla

The Ureters

• Two narrow tubes

• Transport urine from the kidney to the bladder

• Urine drains from the ureters into the bladder through ureteral orifices

The Urinary Bladder

• Oval, hollow, muscular organ

• Reservoir for urine before it
  is excreted

  • Located in the anterior portion of the pelvic cavity behind the pubic  symphysis

  • Lined with rugae (folds that allow the bladder to expand when full  and contract when empty)

The Urethra

• Tube from bladder to exterior of body

  • Has two urinary sphincters

Urethral meatus (urinary meatus)

External opening of the urethra

Prostate gland

• Part of male reproductive system

• Surrounds the urethra

Urination

• Also known as voiding or micturition

• Normal process of excreting urine

  • Requires coordinated contraction of bladder muscles and relaxation of sphincters

  • Forces the urine through the urethra and out through the urethral meatus

Nephrologist

• Physician (specialist)

• Diagnoses and treats diseases and disorders of the kidneys

Urologist

• Physician (specialist)

• Diagnoses and treats diseases and disorders of the urinary system of females and the genitourinary system of males

Nephropathy

• Any disease of the kidney

  • Includes both degenerative and inflammatory conditions

Diabetic nephropathy

Kidney disease resulting from poorly controlled diabetes mellitus

Renal Failure

• Inability of one or both of the kidneys to perform their functions

  • The body cannot replace damaged nephrons

  • When too many nephrons have been destroyed, the result is kidney failure

Azotemia

• Elevation of the blood urea nitrogen (BUN) 

• Uremia can occur when this excess becomes toxic

Uremia (uremic poisoning)

• Results from renal failure; kidney function is compromised

• Urea and waste products normally secreted in the urine are retained in the blood

Acute renal failure (ARF)

Sudden onset and is characterized by uremia

Chronic kidney disease (CKD)

• Progressive loss of renal function over months or years

• Buildup of waste in the blood can be a contributing factor in heart attacks and stroke

End-stage renal disease (ESRD)

• Also known as kidney failure

• Final stage of chronic kidney disease

• Fatal without dialysis or a successful kidney transplant

Nephrotic Syndrome (Nephrosis)

Nephrotic Syndrome (Nephrosis

Edema

excessive fluid accumulation in body tissues

Hyperproteinuria

abnormally high concentrations of protein in urine

Hypoproteinemia

abnormally low concentrations of protein in the blood

Causes of nephrotic syndrome

• Diabetes mellitus

• Infection

• Kidney disorders

Ectopic kidney

• Congenital condition

• One kidney is located in an abnormal position or has fused with the other kidney

Hydronephrosis

Dilation (swelling) of one or both kidneys

Nephritis

Inflammation of the kidney or kidneys

Glomerulonephritis

• Inflammation of the glomeruli

• Red blood cells and proteins leak into urine

Pyonephrosis (nephropyosis)

Suppuration of the kidney

Polycystic kidney disease (PKD)

• Genetic disorder

• Numerous fluid-filled cysts in the kidneys

Renal colic

Acute pain caused by a blockage during passage of a nephrolith (kidney stone)

Renal cell carcinoma

Most common kidney cancer in adults

Wilms tumor (nephroblastoma)

Rare malignant tumor in young children

Stones (Calculi)

• Abnormal mineral deposit formed
  within the body

  • Named for the organ or tissue where it is located

  • Form when waste products in urine separate and crystallize

Nephrolithiasis

• Presence of stones in the kidney

• Travel with the flow of urine

• Named for the location where they become lodged

Urinary tract obstruction

• Blockage that prevents the flow of urine 

• Named for its location

• Commonly caused by stones, congenital abnormalities, or an enlarged prostate

Nephrolith

Kidney stone or renal calculus found in the kidney

Ureterolith

Stone located anywhere along the ureter

Cystolith

Stone located within the urinary bladder

Hydroureter

Distention (swelling) of the ureter with urine that cannot flow because of a ureteral obstruction

Ureteral obstruction

• Blockage of one or both ureters

• Due to congenital abnormality, ureterolith, or other disorders

Ureterorrhagia

Discharge of blood from the ureter

Cystalgia and cystodynia

Pain in the bladder

Cystocele (prolapsed bladder)

Hernia of the bladder through the vaginal wall

Interstitial cystitis

Chronic inflammation within the walls of the bladder

Vesicoureteral reflux (VUR)

Backward flow of urine into the ureters from the bladder

Vesicovaginal fistula

• Abnormal opening between the bladder and vagina

• Allows constant involuntary flow of urine from the bladder into the vagina

Neurogenic Bladder

• Interference with the normal nerve pathways associated with urination

  • The bladder may empty spontaneously, resulting in incontinence

  • Can also prevent the bladder from emptying at all or from emptying completely

• Some of the causes of this condition: 

  • Tumor of the nervous system

  • Trauma

  • Neuropathy

  • Inflammatory condition such as multiple sclerosis

Benign prostatic hyperplasia (BPH)

• Benign prostatic hypertrophy or an enlarged prostate

• Enlargement of the prostate gland

Prostatism

Compression/obstruction of the urethra

Prostate cancer

Common cancer among men

Prostatitis

Inflammation of the prostate gland

Bacterial prostatitis

Usually results from bacteria transported in the urine

Urethrorrhagia

bleeding from the urethra

Urethrorrhea

abnormal discharge from the urethra

Urethrostenosis (urethral stricture)

narrowing of the urethra

Epispadias

• congenital abnormality

  • Male: opening is located on the upper surface of the penis

  • Female: opening is in the region of the clitoris

Hypospadias

• congenital abnormality

  • Male: opening is on the ventral surface (underside) of the penis

  • Female: opens into the vagina

Urinary Tract Infections

• Commonly caused by bacteria

  • Occur more frequently in women

  • Can affect all parts of the urinary system

Urosepsis

Systemic bacterial infection

Cystitis

Inflammation of the bladder

Pyelonephritis

Inflammation of the renal pelvis and kidney

Urethritis

Inflammation of the urethra

Anuria

absence of urine formation by the kidneys

Diuresis

increased output of urine

Dysuria

difficult or painful urination

Enuresis

involuntary discharge of urine

Nocturnal enuresis

urinary incontinence during sleep

Nocturia

frequent and excessive urination during the night

Oliguria

scanty urination

Polyuria

excessive urination

Urinary hesitancy

difficulty in starting a urinary stream

Urinary retention

inability to completely empty the bladder

Incontinence

inability to control the excretion of urine, feces, or both

Urinary incontinence

inability to control the voiding of urine

Overflow incontinence

continuous leaking from the bladder

Stress incontinence

voiding of urine when running, sneezing, laughing, or coughing

Overactive bladder (OAB)

also known as urge incontinence; bladder muscles contract involuntarily

Urinalysis (UA)

Examination of urine for the presence of abnormal elements

Glomerular filtration rate (GFR)

Blood test; checks kidney function

Bladder ultrasound

Handheld ultrasound transducer

Urinary catheterization

Insertion of a tube into the bladder

Cystoscopy

Examination of the urinary bladder using a specialized type of endoscope

Computed tomography (CT scan)

Radiographic imaging of the abdomen

Cystography

• X-ray or fluoroscopy examination of the bladder

• A contrast medium is instilled via a urethral catheter

Intravenous pyelogram (IVP)

X-ray images of the kidneys, ureters, and bladder using an intravenous  contrast medium to clearly visualize the structures

KUB (kidneys, ureters, bladder)

• X-ray study without the use of a contrast medium

• Also referred to as a flat-plate of the abdomen

Retrograde pyelogram

• A contrast medium is instilled and caused to flow upward through the urinary tract 

• Usually as part of cystoscopy

Voiding cystourethrography

Fluoroscopy used to examine the flow of urine from the bladder through the urethra

Digital rectal examination (DRE)

• Palpation of the prostate gland

In this context, the term digital means using a finger

Prostate-specific antigen (PSA) blood test

• Used to screen for prostate cancer

• Measures the amount of prostate-specific antigen present in a blood specimen

• The higher a man’s PSA level, the more likely cancer is present

Diuretics

• Medications administered to increase urine secretion 

• Primarily to rid the body of excess water and salt

• Some foods and drinks (such as coffee, tea, and alcoholic beverages) have a diuretic effect

Other drugs used to treat urinary tract problems

• Antibiotics for urinary tract infections 

• Antispasmodics to block the signals that cause urinary incontinence

Dialysis

• Procedure to remove waste products

  • Used when kidneys no longer function

Hemodialysis

• Waste products are filtered directly from the patient’s blood

• Performed on an external hemodialysis machine, sometimes referred to as an artificial kidney

• Most common type of dialysis