1. Chapter 7 Goals Page 215 Students will be able to:
Name essential organs of the urinary system & describe their locations & functions
Identify common pathologic conditions affecting the urinary system
Recognize how urinalysis is used & interpreted as a diagnostic test
Define urinary system-related forms, prefixes, & suffixes
List & explain laboratory test, clinical procedures, & abbreviations that pertain to the urinary system.
Understand medical terms in their proper contexts, such as medical reports & records.

2. Urinary System
Chapter 7
Pages 215 – 255

3. Page 216
Introduction
When foods containing proteins are used by cells, nitrogenous wastes are released into the bloodstream.
The urinary system removes these from the blood so that they do not accumulate & become harmful.
As blood passes through the kidneys, they filter out wastes to form urine.
Urine leaves the body through the ureters, urinary bladder, & urethra.
Every day, the kidneys process about 200 quarts of blood to filter out 2 quarts of urine.
urine is composed of water, salts, & acids

4. Functions of the Kidneys
Page 216
Functions of the Kidneys
Kidneys:
remove urea, creatinine, uric acid
maintain the proper balance of water, electrolytes, & acids in the body fluids.
secrete hormones such as renin & erythropoietin. .
secrete calciferol, an active form of vitamin D, necessary for the absorption of calcium form the intestine.
degrade & eliminate hormones such as insulin & parathyroid from the bloodstream.
Electrolytes such as sodium (Na+) & potassium (K+) are small molecules that conduct an electrical charge. Electrolytes are necessary for proper functioning of muscles & nerve cells. The kidneys adjust the amounts of water & electrolytes by secreting some substances into the urine & holding back others in the bloodstream for use in the body. This is an example of homeostasis, which is the body’s ability to maintain an equilibrium within its internal environment. Home/o means sameness.
Renin raises blood pressure (to keep blood moving through the kidney).
Erythropoietin (EPO) is a hormone that stimulates red blood cell production in the bone marrow.

5. Anatomy of the Major Organs
Page 216
Anatomy of the Major Organs
The kidney is one of two bean-shaped organs behind the abdominal cavity on either side of the spine in the lumbar region.
A cushion of adipose tissue & fibrous connective tissue surrounds each kidney for protection. They each weigh about 4 to 6 ounces.
They consist of an outer cortex region & an inner medulla region.
The hilum (where blood vessels & nerves pass into the kidney) is a depression on the medial boarder.
Adipose = fatty
Cortex = bark, as the bark of a tree
Medulla = marrow

6. Anatomy of the Major Organs: Cont.
Pages 216 – 217
Anatomy of the Major Organs: Cont.
Ureter = one of two muscular tubes (16 to 18 inches long) lined with mucus membrane.
They carry urine in peristaltic waves from the kidneys to the urinary bladder.
Urinary bladder = a hollow, muscular sac, is a temporary reservoir for urine.
Trigone = a triangular region at the base of the bladder where the ureters enter & the urethra exits.
Urethra = a tube that carries urine from the urinary bladder to the outside of the body.
urinary meatus = the external opening of the urethra
The process of expelling urine through the urethra is called urination or voiding.
The female urethra, about 1 ½ inches long, lies anterior to the vagina & vaginal meatus. The male urethra, about 8 inches long extends downward through the prostate gland to the urinary meatus at the tip of the penis.

7. Physiology: How the Kidney’s Produce Urine
Page 218
Physiology: How the Kidney’s Produce Urine
Blood enters each kidney from the aorta by way of the right & left renal arteries. After the renal artery enters (at the hilum), it branches into smaller & smaller vessels called arterioles.
Because the arterioles are small, blood passes through them slowly but constantly. Blood flow through the kidney is so essential that the kidneys have their own special device for maintaining blood flow. If blood pressure falls in the vessels of the kidney, so that blood flow diminishes, the kidney produces renin & discharges it into the blood. Renin promotes the formation of a substance that stimulates the contraction of arterioles. This increases blood pressure & restores blood flow in the kidneys to normal.

8. Physiology: How the Kidney’s Produce Urine: Cont.
Page 219
Physiology: How the Kidney’s Produce Urine: Cont.
Each arteriole in the cortex of the kidney leads into a mass of very tiny, coiled, & intertwined smaller blood vessels called glomeruli.
Attached to each glomerular capsule is a long, twisted tube called a renal tubule.
Each glomerulus (singular) is a collection of tiny capillaries formed in the shape of a small ball. There are about 1 million glomeruli in the cortex region of each kidney.
The kidney produce urine by filtration. As blood passes through the many glomeruli, the thin walls of each glomerulus (the filter) permit water, salts, sugar, & urea (with other nitrogenous wastes such as creatinine & uric acid) to leave the bloodstream. These materials collect in a tiny, cup-like structure, a glomerular (Bowman) capsule, that surrounds each glomerulus. The walls of the glomeruli prevent large substances, such as proteins & blood cells, from filtering into the urine. The substances remain in the blood & normally do not appear in urine.

9. Physiology: How the Kidney’s Produce Urine: Cont.
Page 219
Physiology: How the Kidney’s Produce Urine: Cont.
The final process in the formation of urine is secretion of some substances such as potassium, acids & drugs from the bloodstream into the renal tubule. Each renal tubule, now containing urine (95% water & 5% urea, creatinine, salts & acids) connects to a larger collecting tubule.
Nephron = a unit which is the combination of a glomerulus & a renal tubule.
As water, sugar, urea, & other wastes pass through the renal tubule, most of the water, all of the sugar, & almost all of the sodium return to the bloodstream through tiny capillaries surrounding each tubule. This active process of reabsorption ensures that the body retains essential substances such as sugar, water, & sodium while allowing waste products to be excreted in the urine.

10. Physiology: How the Kidney’s Produce Urine: Cont.
Page 221
Physiology: How the Kidney’s Produce Urine: Cont.
All collecting tubules lead to the renal pelvis, a basin-like area in the central part of the kidney. Small cup-like regions of the renal pelvis are called calices (singular calix)
The renal pelvis narrows into the ureter

11. Physiology: How the Kidney’s Produce Urine: Cont.
Page 221
Physiology: How the Kidney’s Produce Urine: Cont.
The ureter carries the urine to the urinary bladder.
The bladder temporarily stores urine.
Sphincter muscles controls the exit area of the bladder to the urethra.
As the bladder fills & pressure increases at its base, an individual notices a need to urinate & voluntarily relaxes sphincter muscles.

12. Page 228
Urinalysis
Urinalysis = an examination of urine to determine the presence of abnormal elements that may indicate various pathologic conditions. It is an inexpensive, noninvasive test that provides valuable information not only about the contents of urine, but about diseases affecting the body as a whole.
The following are some of the tests included in a urinalysis:

13. Normal urine = yellow (straw-colored)
Pages 228 – 229
Color
Normal urine = yellow (straw-colored)
Water in the urine = A colorless, pale urine
Smoky-red or brown color of urine = large amounts of blood. (Foods such as beets & certain drugs also can produce a red coloration)
Appearance
Normal urine = clear.
Cloudy (turbid) urine = a urinary tract infections with pus & bacteria
Pyuria = pus
Bacteriuria = bacteria

14. Pages 228 – 229 pH
It indicates to what degree a solution is acid or alkaline (basic).
Normal urine = slightly acidic pH of 6.5.
Alkaline pH = infection of the bladder owing to the actions of bacteria in the urine that break down urea & release ammonia.
Bilirubin
This pigment substance may be present in the urine of patients with liver disease.
Urobilinogen, a breakdown product of bilirubin, also may be found in the urine.
Bilirubin - results from hemoglobin breakdown

15. Pages 228 – 229
Protein
When urinary tests for protein become positive, albumin is usually responsible. Albumin is the major protein in protein in blood plasma. If it is detected in urine, it may indicate a leak in the glomerular membrane, which allows albumin to enter the renal tubule & pass into the urine.
Through more sensitive testing, smaller abnormal amounts of albumin may be detected, revealing microalbuminuria, when ordinary tests are negative. Microalbuminuria is recognized as the earliest sign of renal involvement in diabetes mellitus.
Small amounts of protein are normally found in the urine but not in sufficient quantity to produce a positive result by ordinary methods of testing.

16. Pages 228 – 229 Specific gravity
The specific gravity of urine reflects the amounts of wastes, minerals, & solids in the urine. It is a comparison of the density of urine with that of water.
higher-than-normal specific gravity = diabetes mellitus, because of the presence of sugar.
Sediment & casts
Presence of abnormal particles in the urine = a sign of a pathologic condition.
Such particles, which may settle to the bottom of a urine sample as sediment, may include cells, bacteria, crystals, & casts.
Glucose
Sugar = diabetes mellitus.
In diabetes mellitus, there is excess sugar in the bloodstream, which leads to the "spilling over" of sugar into the urine.

17. Pages 228 – 229
Ketone bodies
Ketones accumulate in blood & urine when the body breaks down fat, instead of sugar, for fuel.
Ketonuria = diabetes mellitus or starvation
DM = when cells deprived of sugar must use up their available fat for energy.
Starvation = when sugar is not available, ketonuria & ketosis occurs as fat is catabolized abnormally.
Ketones in the blood are dangerous because they increase the acidity of the blood. If severe, this may lead to coma & death.
Ketones are formed when fatty acids are broken down in the liver.

18. Pages 228 – 229
Phenylketonuria (PKU)
phenylalanine in the urine = a rare condition in which a baby is born unable to break down the amino acid phenylalanine. This results in high blood levels of phenylalanine which can lead to mental retardation.
Today this test is usually done by pricking the newborn's heel to obtain a small blood sample.
If phenylalanine is detected, the infant is fed a diet excluding phenylalanine. Affected children remain on this diet until adulthood.

19. Pathologic Terminology
Pages 229 – 231
Pathologic Terminology
Kidney
glomerulonephritis
Inflammation of the glomeruli within the kidney.
interstitial nephritis
Inflammation of connective tissue that lies between the renal tubules.
nephrolithiasis
Kidney stones (renal calculi)
nephrotic syndrome (nephrosis)
Group of clinical signs & symptoms caused by excessive protein loss in urine.
Wilms tumor
Malignant tumor of the kidney occurring in childhood
Glomerulonephritis - This condition can follow a streptococcal infection. It results in leaky glomeruli, hematuria, red blood cell casts, albuminuria, & when severe renal failure, & uremia. Drugs may be useful to control inflammation, & dialysis or renal transplantation may be necessary if uremia occurs
interstitial nephritis - Connective, supportive tissue lying between the renal tubules is made up of renal interstitial cells. Interstitial cells in any organ are found in addition to the essential, main functional cells, which make up the parenchyma. The parenchyma in the kidney consists of the glomeruli & the renal tubules (nephrons). Acute interstitial nephritis, an increasingly common disorder, may develop after use of NSAIDs (non-steroidal anti-inflammatory drugs, such as aspirin & ibuprofen) & other drugs. It may be marked by fever, skin rash, & eosinophils in the blood & urine
Nephrolithiasis - Kidney stones usually are composed of uric acid or calcium salts. Stones often lodge in the ureter or bladder, as well as in the renal pelvis, & may require removal by lithotripsy or surgery
nephrotic syndrome (nephrosis) - Nephrotic syndrome may be follow glomerulonephritis or exposure to toxins or certain drugs, immune diseases, & other pathologic conditions, such as diabetes mellitus & cancer. Two important signs of nephrotic syndrome are edema (swelling caused by fluid in tissue spaces) & hypoalbuminemia. Both of these changes are caused by massive leakage of protein into urine
Wilms tumor - This tumor may be treated with surgery, radiation therapy, & chemotherapy.

20. Pages 230 – 231 polycystic kidney disease (PKD)
Multiple fluid-filled sacs (cysts) within & on the kidney.
pyelonephritis
Inflammation of the lining of the renal pelvis & renal parenchyma
renal cell carcinoma (hypernephroma)
Cancerous tumor of the kidney in adulthood
renal failure
Decrease in excretion of wastes results from impaired filtration function
renal hypertension
High blood pressure resulting from kidney disease
polycystic kidney disease (PKD) - There are two types of hereditary PKD. One type usually is asymptomatic (without symptoms) until middle age & then age is marked by hematuria, urinary tract infections, nephrolithiasis, & renal failure. The other type of PKD occurs in infants or children & results in renal failure
Pyelonephritis - The parenchyma of an organ is its essential & distinctive tissue. Nephrons make up the renal parenchyma. Bacterial infection in the urinary tract causes collections of pus to form in the kidney, often associated with bacteria spilling into the bloodstream. Urinalysis reveals pyuria. Treatment consists of antibiotics & surgical correction of any obstruction to urine flow
renal cell carcinoma (hypernephroma) - This tumor accounts for 2% of all cancers in adults. Hematuria is the primary abnormal finding, & the tumor often metastasizes to bones & lungs. Nephrectomy or partial nephrectomy is the primary treatment
renal failure - A large number of conditions, including high blood pressure, infection, & diabetes, can lead to renal failure, which may be acute (ARF) or chronic (CRF), reversible or progressive, mild or severe. A newer classification or chronic kidney disease (CKD) stages its severity by the level of creatinine clearance & glomerular filtration rate (GFR), ranging from normal (stage 1) to end-stage renal failure (stage 5)
renal hypertension - Renal hypertension is a type of secondary hypertension (high blood pressure caused by an abnormal condition such as glomerulonephritis). However, the most common type of high blood pressure is essential hypertension, or primary hypertension. In essential hypertension there is no obvious underlying medical condition. Chronic essential hypertension can damage blood vessels potentially resulting in stroke, myocardial infraction (heart attack), heart failure, or renal failure

21. Pathologic Terminology: Cont.
Pages 231
Pathologic Terminology: Cont.
Urinary Bladder & Associated Conditions
bladder cancer
Malignant tumor of the urinary bladder
diabetes insipidus (DI)
Antidiuretic hormone (ADH) is not secreted, or there is a resistance of the kidney to ADH
diabetes mellitus (DM)
Insulin is not secreted adequately or tissues are resistant to its effects
bladder cancer - Bladder cancer occurs more frequently in men (often smokers) & in persons older than 50 years of age, especially industrial workers exposed to dyes & leather-tanning agents. Signs & symptoms include gross (visible to the naked eye) or microscopic hematuria & dysuria. Cystoscopy with biopsy is the most common diagnostic procedure. Staging of the tumor is based on the depth to which the tumor invades the bladder wall & presence of metastasis. Superficial tumors are removed by electro-cauterization (burning). Cystectomy, chemotherapy, & radiation therapy are treatments for disease that has spread deeply into the bladder wall, to regional lymph nodes, or to distant organs
diabetes insipidus (DI) - In DI, the kidney produces large amounts of dilute urine (polyuria). Lack of ADH prevents water from being absorbed into the blood through the renal tubules. Insipidus means tasteless, reflecting very dilute & watery urine, not sweet as in diabetes mellitus. The term diabetes comes from the Greek diabainein, meaning to pass through. Both types of diabetes (insipidus & mellitus) are marked by polyuria & polydipsia
diabetes mellitus (DM) - The major signs & symptoms of diabetes mellitus are glycosuria, hyperglycemia, polyuria, & polydipsia. Without insulin, sugar cannot leave the bloodstream & is not available to body cells for energy. Sugar remains in the blood (hyperglycemia) & spills over into the urine (glycosuria). Mellitus means sweet, reflecting the content of the urine. The term diabetes, when used alone, refers to diabetes mellitus

22. Laboratory Tests & Clinical Procedures
Page 232
Laboratory Tests & Clinical Procedures
Laboratory Tests
blood urea nitrogen (BUN)
Measurement of urea levels in blood
creatinine clearance
Measurement of the rate at which creatinine is cleared from the blood by the kidney
blood urea nitrogen (BUN) - Normally, the blood urea level is low because urea is excreted in the urine continuously. However, when the kidney is diseased or fails, urea accumulates in the blood (uremia), leading to unconsciousness & death.
creatinine clearance - This is an important test to assess the functioning of the kidney. A blood sample is drawn & the creatinine concentration in blood is compared with the amount of creatinine excreted in the urine during a fixed time period. If the kidney is not functioning well in its job of clearing creatinine from the blood, the amount of creatinine in the blood will be high relative to the amount in urine. Creatinine clearance is a useful indicator of the glomerular filtration rate (GFR), which normally is 90 to 120 mL/minute.

23. Laboratory Tests & Clinical Procedures: Cont.
Page 232
Laboratory Tests & Clinical Procedures: Cont.
Clinical Procedures
X-Ray Studies
CT urography
X-ray images obtained using computed tomography (CT) show multiple cross-sectional & other view of the kidney
kidneys, ureters, & bladder (KUB)
X-ray examination (without contrast) of the kidneys, ureters, & bladder.
CT urography - CT scanners show multiple views of the kidney, taken with or without contrast material. Two main indications are to detect kidney stones & to evaluate patients with hematuria
kidneys, ureters, & bladder (KUB) - A KUB study demonstrates the size & location of the kidneys in relation to other organs in the abdominopelvic region.

24. X-ray examination (with contrast) of the blood vessels of the kidney
Pages 232 – 233
renal angiography
X-ray examination (with contrast) of the blood vessels of the kidney
retrograde pyelogram (RP)
X-ray image of the renal pelvis & ureters after injection of contrast through a urinary catheter into the ureters from the bladder.
voiding cystourethrogram (VCUG)
X-ray image (with contrast) of the urinary bladder & urethra obtained while the patient is voiding
renal angiography - This procedure helps diagnosis obstruction or construction of blood vessels leading to the kidney. The same changes can be seen on CT & MRI urography
retrograde pyelogram (RP) - This technique is useful in locating urinary stones & obstructions
voiding cystourethrogram (VCUG) - The bladder is filled with contrast material, followed by fluoroscopy (real-time x-ray imaging). Reflux of contrast into the ureters is abnormal & may occur with recurrent urinary tract infections

25. Laboratory Tests & Clinical Procedures: Cont.
Page 233
Laboratory Tests & Clinical Procedures: Cont.
Clinical Procedures
Ultrasound Examination
ultrasonography
Imaging of urinary tract structures using high-frequency sound waves
Ultrasonography - Kidney size, tumors, hydronephrosis, polycystic kidney disease, & ureteral & bladder obstruction can be diagnosed using ultrasound techniques.

26. Laboratory Tests & Clinical Procedures: Cont.
Page 233
Laboratory Tests & Clinical Procedures: Cont.
Clinical Procedures
Radioactive Study
radioisotope scan
Image of the kidney obtained after injecting a radioactive substance (radioisotope) into the bloodstream
radioisotope scan - Pictures show the size & shape of the kidney (renal scan) & its functioning (renogram). These studies can indicate narrowing of blood vessels, diagnose obstruction, & determine the individual functioning of each kidney

27. Laboratory Tests & Clinical Procedures: Cont.
Page 233
Laboratory Tests & Clinical Procedures: Cont.
Clinical Procedures
Magnetic Resonance Imaging
MRI urography
Changing magnetic field produces images of the kidney & surrounding structures in three planes of the body.
MRI urography - The patient lies within a cylindrical magnetic resonance machine, & images are made of the pelvic & retroperitoneal regions using magnetic waves. This test is useful in visualizing tumor invasion of blood vessels, lymph nodes, & adjacent tissues.

28. Laboratory Tests & Clinical Procedures: Cont.
Pages 233 – 235
Laboratory Tests & Clinical Procedures: Cont.
Other Procedures
cystoscopy
Direct visualization of the urethra & urinary bladder with an endoscope (cystoscope).
dialysis
Process of separating nitrogenous waste materials from the blood
lithotripsy
Urinary tract stones are crushed
renal angioplasty
Dilation of narrowed areas in renal arteries
renal biopsy
Removal of kidney tissue for microscopic examination
Cystoscopy - The procedure can be preformed in two ways. Flexible cystoscopy uses a thin fiber optic cystoscopy & is used for diagnosis & check-ups of the urinary bladder. Rigid cystoscopy uses a hollow metal tube, passed through the urethra & into the bladder. It is used to take biopsy samples, remove polyps, or perform laser treatments
Dialysis - Dialysis is used to treat acute or chronic renal failure & some cases of drug use. There are two methods:
1) Hemodialysis (HD) uses an artificial kidney machine that receives waste-filled blood from the patient's bloodstream, filters it through an artificial porous membrane (dialyzer), & returns the dialyzed blood to the patient's body. An arteriovenous fistula (communication between an artery & a vein) is created surgically to provide easy access for hemodialysis
2) Peritoneal dialysis (PD) uses a catheter to introduce fluid into the peritoneal (abdominal) cavity. Waste material, such as urea, in the capillaries of the peritoneum pass out of the bloodstream & into the fluid. The fluid (with wastes) is then removed by catheter. When used to treat patients with chronic kidney disease, PD may be performed continuously by the patient without mechanical support (CAPD - continuous ambulatory PD) or with the aid of a mechanical apparatus used at night during sleep
Lithotripsy - The extracorporeal method use shock waves directed toward the stone from the outside of the body (extra = outside, corpor/o = body). The patient receives light sedation or an anesthetic. Stones pass from the body in urine after the procedures. Abbreviation is ESWL (extracorporeal shock wave lithotripsy)
renal angioplasty - A balloon attached to a catheter is inserted into the artery & then inflated to enlarge the vessel diameter. Afterward, stents (metal-mesh tubes) may be inserted to keep the vessel open. This procedure is used to treat renal hypertension & to preserve renal function
renal biopsy - Biopsy may be performed at the time of surgery (open) or through the skin (percutaneous, or closed). When the latter technique is used, the patient lies in the prone position; then, after administration of local anesthesia to the overlying skin & muscles of the back, the physician inserts a biopsy needle down into the kidney. Several specimens are obtained for examination by a pathologist

29. Laboratory Tests & Clinical Procedures: Cont.
Page 236
Laboratory Tests & Clinical Procedures: Cont.
Other Procedures
renal transplantation
Surgical transfer of a kidney from a donor to a recipient.
urinary catheterization
Passage of a flexible, tubular instrument through the urethra into the urinary bladder
renal transplantation - Patients with renal failure may receive a kidney from a living donor, such as an identical twin (isograft) or other person (allograft), or from a patient at the time of death (cadaver transplant). Best result occur when the donor is closely related to the recipient - 98% of transplanted kidneys survive for 1 year on longer
urinary catheterization - Catheters are used primarily for short- or long-term drainage of urine. A Foley catheter is an indwelling (left in the bladder) catheter held in place by a balloon inflated with liquid.