Urinary Tract Conditions

Overview

What Is It?
As you age, the structure of your kidneys can change, reducing their ability to remove wastes. Illness and injury can also affect the filtering ability of the kidneys or block urine's passage.

Your urinary system works with other organs to get rid of wastes and keep chemicals and water in the body balanced. As an adult woman, you eliminate about a quart and a half of urine each day, but the amount can vary depending on the amount of fluid and food you've consumed and how much you lose through sweating and breathing. Some medications can affect the quantity of urine your body eliminates.

When your body uses proteins derived from the foods you eat, it creates a waste product called urea that is carried in the bloodstream to the kidneys, two bean-shaped organs approximately the size of fists. They are located just below the rib cage near the middle of the back. Each kidney has about a million tiny filtering units called nephrons, which remove urea from the blood.

A ball of small blood capillaries (a glomerulus) and a small tube called a renal tubule comprise a nephron. The kidneys remove or return chemicals such as phosphorus, potassium and sodium in quantities needed to maintain optimal blood levels of these substances. Urea, water and other waste products create urine as the substances move through the nephrons and down the kidney's renal tubules.

The kidney also releases three vital hormones: erythropoietin which stimulates production of red blood cells in bones; renin, a blood-pressure regulator; and the active form of vitamin D, which maintains calcium levels in bone.

Urine exits the kidneys through two thin tubes about eight to 10 inches long called ureters, which carry the fluid to the bladder, a hollow muscular organ that stores urine. Ureter muscles tighten and relax to pump urine downward and away from the kidneys. The process is more or less continuous, with minute quantities of urine emptying into the bladder about every 10 to 15 seconds. If the urine gets stuck in the ureters or backs up, a kidney infection can result.

Shaped like a balloon, the bladder sits in the pelvis and stores urine until you are ready to urinate. As it becomes fuller, it swells into a round shape and then shrinks when it is emptied. A healthy urinary system can hold up to 16 ounces of urine for two to five hours. Bladder nerves send signals to let you know when to urinate; the signals grow steadily more urgent as the bladder fills.

To keep urine from leaking, circular muscles called sphincters close tightly around the opening of the bladder. When you decide to urinate, bladder muscles tighten and sphincter muscles relax, and the urine is pushed down the urethra.

As you age, the structure of your kidneys can change, reducing their ability to remove wastes. Illness and injury can also affect the filtering ability of the kidneys or block urine's passage. Urinary system muscles also tend to weaken as you grow older, leading to increased incidence of urinary tract infections and incontinence.

Urinary system disorders are widespread. According to the National Kidney Foundation, approximately 26 million Americans have chronic kidney disease, and most do not know it. Millions more are at risk. Incontinence and overactive bladder are two of the most common health problems among women. And 85,790 Americans died of end-stage renal disease in 2005.

Major Urinary System Disorders

Health care professionals often use the term "renal function" when talking about the kidneys; if both kidneys are healthy, you have 100 percent renal function. If one becomes nonfunctional or is donated for a transplant operation, you will still be healthy, even with only 50 percent of renal function. However, if function slips below 20 percent, serious health problems arise because the kidneys can no longer perform their function of regulating water and chemicals and removing waste. Levels below 10 to 15 percent necessitate dialysis or transplantation.

Renal function levels below 10 to 15 percent necessitate dialysis or transplantation. Unfortunately, symptoms of chronic renal failure (a gradual loss of function) may go undetected for several years and often do not become noticeable before kidney function falls to 25 percent or less.

Acute renal failure denotes a sudden onset of renal failure, such as that caused by an accident, certain drugs or poison. The kidneys may recover or the damage may be permanent. If the kidneys stop working entirely, the result is a condition called uremia, in which the body fills with extra water and waste products, leading to swelling in the hands or feet, fatigue and weakness. End-stage renal disease (ESRD) refers to when the kidneys have lost all or nearly all function.

Specific kidney conditions include:

Analgesic Nephropathy

Improper use of over-the-counter painkillers, or analgesics, can lead to kidney failure. These products include aspirin, acetaminophen, ibuprofen and naproxen sodium, all of which are safe for most people when taken at the recommended dosages. However, combining these drugs or taking them when you have certain conditions boosts your risk of kidney disease. You should avoid these medications if you have an autoimmune disease such as lupus, advanced age, chronic kidney conditions or have recently binged on alcohol.

If you have any of these conditions, make sure your health care professional and pharmacist are consulted before you risk taking an analgesic, since short-term use can cause acute (temporary) kidney failure.

Taking one or more of these products daily for several years can cause analgesic nephropathy, chronic kidney disease leading gradually to end-stage renal disease (ESRD). Combination painkillers (such as aspirin and acetaminophen) are especially dangerous. If you find you need painkillers often, talk to a health care professional about the best options for protecting your kidneys.

Cystocele

A cystocele, occurs when the pelvic floor muscles, which form the wall between the bladder and vagina, weaken, allowing the bladder to drop into the vagina. The consequences are discomfort and voiding difficulties, such as urine leakage or incomplete bladder emptying.

There are three grades of cystocele:

• Grade 1: the bladder drops a short way into the vagina
• Grade 2: the bladder sinks to the opening of the vagina
• Grade 3: the bladder bulges through the vaginal opening

Interstitial Cystitis (IC)

Interstitial cystitis (IC) may also be called painful bladder syndrome, urethral syndrome and frequency-urgency syndrome. It is an inflammatory condition of the lining of the bladder.

The inflammation associated with this chronic bladder disorder can cause diminished bladder capacity or size, glomerulations (pinpoint bleeding) and (rarely) ulcers in the bladder lining. Rarely, in severe cases, scarring and stiffening of the bladder can occur. Although the cause of this disorder is unknown, research shows that it may be associated with other diseases such as vulvodynia (vulvar or vaginal pain), fibromyalgia, irritable bowel syndrome (IBS) and endometriosis. Interstitial cystitis affects an estimated 1.3 million Americans, more than 1 million of whom are women.

Typical IC-associated sensations include discomfort, pressure, tenderness or intense pain in the bladder and surrounding pelvic area. The intensity of pain may shift as the bladder fills or empties. Other symptoms include pain associated with intercourse and frequent and/or urgent need to urinate (women with severe IC may urinate as many as 60 times a day). Symptoms often get worse before or during menstruation and after sexual activity.

No one knows for sure what causes IC; theories point to an autoimmune disease, abnormality in the urine, hereditary condition, infection or allergic condition.

Glomerular diseases

Diseases that damage the glomeruli—the kidney's filtering units—can lead to kidney failure. Two major categories of glomerular diseases are:

• glomerulonephritis, inflammation of the membrane tissue in the kidney that filters wastes and extra fluid from the blood
• glomerulosclerosis, scarring or hardening of tiny blood vessels in the kidney

When the glomeruli are damaged, protein and blood can seep into the urine, and waste products can accumulate in the blood. If too much of the protein albumin is lost, the blood is less able to absorb extra fluid.

Glomerular diseases are indicated by:

• proteinuria
• hematuria
• reduced glomerular filtration rate (inefficient waste filtering)
• hypoproteinemia (low levels of protein in the blood)
• swelling, or edema

The diseases have many causes, including:

• Autoimmune diseases, such as lupus. Autoimmune diseases are conditions that develop as a result of the immune system attacking healthy tissue instead of combating invading bacteria or viruses.
• Hereditary nephritis, also called Alport syndrome. A family history of chronic glomerular disease or impaired vision may stem from this syndrome, and men are more likely to progress to chronic renal failure and/or vision loss.
• Infection-related glomerular disease, such as strep throat, heart infection (bacterial endocarditis), HIV or skin infection (impetigo). The kidneys usually recover from infection-related damage, but sometimes damage is permanent and ESRD results.

Hematuria

Hematuria is a term used for the presence of red blood cells in the urine. Sometimes hematuria is visible, but in many cases the urine appears normal. Hematuria is not a disease in itself, but a sign of some other condition.

The cause may be a serious one, such as bladder or kidney cancer, but more often the cause is relatively benign. Exercise can cause episodic hematuria, for example. Obvious blood in the urine is often associated with bladder infections or kidney stones. Still, you should check with a health care professional any time you see blood in your urine or follow up if a urinalysis shows red blood cells in your urine.

To identify the cause of hematuria, your doctor may order various tests, such as urinalysis, blood tests, ultrasound, intravenous pyelogram or CT urogram, or may examine your bladder with a cystoscope. If white blood cells are present in the urine, a urinary tract infection or kidney disease may be the cause.

Treatment is tailored to the cause of the hematuria. If it is not caused by a serious condition, no treatment is necessary.

End-Stage Renal Disease (ESDR) and Kidney Failure

The early stages of kidney disease may not cause noticeable symptoms. However, symptoms may include frequent headaches, fatigue or an all-over itch. Worsening disease can cause urination patterns to change (becoming more or less frequent), appetite loss, nausea and vomiting, swelling or numbness in the hands or feet, drowsiness, difficulty concentrating, skin darkening and muscle cramps. Treatment generally requires dialysis or transplant, described in the treatment section.

Diabetes is the leading cause of ESRD.

When diabetes is undiagnosed or poorly controlled, excess sugar circulates in the blood, leading to higher blood flow into the kidney and glomerular scarring. Diabetic nephropathy is the term used for such damage, which can be delayed or prevented by maintaining healthy blood sugar levels. If you have diabetes, high blood pressure or a genetic condition called polycystic kidney disease, your health care team will monitor your condition to prevent or limit the damage to the kidneys. Such damage may lead to renal failure and ESRD.

Bladder Cancer and Kidney Cancer

Signs and symptoms of bladder cancer include blood in the urine (which may be bright red or rusty in appearance or only seen under the microscope), painful or frequent urination or feeling the urge to urinate even though the bladder is empty.

Renal cell cancer is the most common form of kidney cancer. As the cancer grows, it may spread to nearby organs, such as the liver, colon or pancreas, or may disperse (metastasize) to other parts of the body. Cancer cells often spread to lymph nodes, bean-shaped organs that produce infection-fighting cells. Signs and symptoms of renal cell cancer include blood in the urine, back or abdominal pain, or a mass on the kidney. Many kidney cancers are diagnosed by ultrasound or CT examination performed for other medical reasons.

Kidney or Ureter Stones

Stones, or calculi, are usually formed in the kidneys but may be found anywhere in the urinary system. Stones are among the most painful and most common urinary tract disorders—an estimated five to 10 percent of Americans will have a kidney stone at some point in their lives. Men are afflicted with kidney stones more often than women, and Caucasians are more susceptible than African Americans. Stones are most likely to occur between the ages of 20 and 50 in women (later in men) and are more likely to occur in people who have previously had stones.

Kidney stones vary widely in size and in the amount of pain they cause. Most are passed from the body without assistance, but there are a variety of strategies to treat stones that linger.

A kidney stone forms from crystals that separate from urine and accumulate on the kidney's inner surfaces. Urine contains chemicals that prevent crystal formation, but in some people the process doesn't work well and they develop stones. If the stones are small enough, they travel through the urinary tract and leave the body without causing symptoms.

Most stones contain calcium and either oxalate or phosphate—all three are part of a healthy diet. Less common are struvite or infection stones, caused by urinary tract infections. Terms used to describe stones include nephrolithiasis (kidney stones), urolithiasis (urinary tract stones) and ureterolithiasis (ureter stones).

Risk for kidney stones is higher in those with family histories of stones; those who have urinary tract infections, kidney disorders and metabolic disorders such as hyperparathyroidism, cystinuria (too much of an amino acid called cystine) or hyperoxaluria (excess production of oxalate salt); and those with a disease called renal tubular acidosis. High levels of urinary calcium lead to crystals of calcium oxalate or calcium phosphate, which can grow into painful stones.

Other risk factors include:

• hyperuricosuria—a disorder of uric acid metabolism
• gout
• excess intake of vitamin D
• blockage of the urinary tract
• use of diuretics or calcium-based antacids
• chronic bowel inflammation, intestinal bypass surgery or ostomy surgery

The initial symptom is usually sudden, intense pain, provoked by the movement of a stone in the urinary tract. The feeling is usually a sharp, very severe, cramping pain in the back and side in the kidney or lower abdominal region. Nausea and vomiting may occur, and the pain may spread to the groin. A stone too large to pass easily causes continuing pain in the muscles in the ureter as they try to squeeze the stone into the bladder. As the stone approaches the bladder, you may feel compelled to urinate more frequently or feel a burning pain when you urinate.

Note: Fever and chills suggest an infection that warrants a health care professional's immediate attention.

Kidney stones are usually diagnosed via x-ray or sonogram. Urinalysis often shows blood cells. A health care professional may order blood and urine tests to detect abnormal substances that may be stimulating stone production. A type of x-ray called an intravenous pyelogram (IVP) or spiral CT scan may be used to scan the urinary system as well. In addition, to help determine what's causing your kidney stones and, therefore, to plan appropriate prevention measures, your health care professional may ask you to urinate through a strainer designed to catch any stones you pass so the stones can be analyzed for their makeup.

Neurogenic Bladder

The smooth functioning of the urinary system depends on muscles and nerves working properly to store urine in the bladder and release it at the appropriate time. Nerves running between the bladder and the brain tell the brain when the bladder is full and tell the bladder when it's OK to relax and release the urine. When the nerves that carry these messages malfunction, a condition called neurogenic bladder results.

Some possible causes of neurogenic bladder include:

• diabetes
• accidents that cause trauma to the brain or spinal cord
• nerve problems such as multiple sclerosis, strokes, or Parkinsonism
• congenital nerve problems such as spina bifida

Primary effects of neurogenic bladder are:

• urine leakage, when muscles holding the urine do not get the message to stay tight to retain the urine
• urine retention, when the muscles holding in the urine do not get the message that they should let go
• damage to the tiny blood vessels in the kidneys that results when the bladder gets too full. This prevents good drainage, causing back pressure.
• bladder infection or infection of the kidneys

Polycystic Kidney Disease (PKD)

This genetic disorder causes multiple cysts to grow in the kidneys and gradually displace functioning parts of the kidney. PKD symptoms sometimes show up in childhood, including frequent headaches and back or side pain. Other symptoms include high blood pressure, urinary tract infections and kidney stones, as well as blood or protein in urine. The disease, however, may exhibit no symptoms for years. There are two forms of PKD :

• Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the most common, affecting one in 400 to one in 1,000 adults. Symptoms include high blood pressure, and the condition can lead to renal failure.
• Autosomal Recessive Polycystic Kidney Disease (ARPKD), also known as infantile PKD , is far less common, affecting only one in 10,000 to one in 20,000 at a far younger age, including newborns, infants and children. It can be detected during pregnancy through amniocentesis or chorionic villus sampling.

Proteinuria

Proteinuria denotes high levels of protein in the urine. When kidneys are healthy, filtering units called glomeruli remove waste products but leave behind nutrients the body needs, such as proteins, which are usually too large to pass through kidney filters unless the kidneys are damaged. When albumin, a small protein, seeps into the urine, blood vessels lose their capacity to reabsorb fluid from the tissues. The fluid then builds up in hands, feet or ankles, causing swelling.

Symptoms of proteinuria include foamy-appearing urine and swelling in the hands, feet, abdomen or face. But the condition can also be invisible, producing no symptoms. Laboratory testing is the only way to measure proteinuria.

One basic test uses a chemically treated strip of paper to detect protein levels. The paper changes color if dipped in urine with high levels of protein. A more sensitive test, which can detect microalbuminuria, requires urine collection over 24 hours. You may also have to provide a blood sample for creatinine and urea nitrogen testing (see kidney disease and renal failure). If blood levels of these two substances are high, kidney function is impaired.

Proteinuria is a sign of glomerulonephritis, also called nephritis (inflammation of the kidney). Diabetes, hypertension and various kidney diseases can cause the inflammation, which can lead to renal failure and, ultimately, end-stage renal disease (ESRD).

The severity of damage correlates with the level of proteinuria and whether the protein content is entirely albumin or includes other proteins (the more kinds of proteins, the greater the damage).

If you have diabetes, you should be regularly checked for proteinuria. The National Kidney Foundation also recommends that all routine checkups include proteinuria testing, especially for those at high risk.

Small amounts of albumin in the urine—microalbuminuria—is the first sign of declining kidney function in people with diabetes (the leading cause of ESRD). As function continues to slide, the level of albumin rises and the condition becomes proteinuria.

The second most common cause of ESRD is high blood pressure. Proteinuria and high blood pressure together indicate deteriorating kidney function. Medication for hypertension must be started, or renal failure will result. African Americans are at higher risk for high blood pressure and the resulting kidney problems than Caucasians.

Proteinuria also strikes more frequently in Native Americans, Hispanic Americans, Pacific Islanders, older people and overweight people. If you have a family history of kidney disease, you should have your urine tested regularly.

Urinary Incontinence

Many factors can cause urinary incontinence, or a loss of bladder control resulting in the involuntary release of urine. Incontinence is a problem for millions of American women, particularly those aged 65 and older. It is especially common in women who are pregnant or have recently delivered a baby and in elderly women. Incontinence can also affect men.

Bladder control, or continence, is the result of a system of nerves and muscles working together correctly. If the muscles at the bladder neck or in the pelvic floor are weak, laughter, sneezing or heavy lifting can cause leakage.

A condition called urge incontinence arises when the bladder muscle is overactive and contracts involuntarily. Since the occurrence of urge incontinence is unpredictable, it is more devastating to one's quality of life. Overactive bladder (OAB) occurs when you void more than eight times in the day and twice at night, have a strong urge to void, and/or urge incontinence. It affects millions of Americans, both men and women.

Overflow incontinence occurs when your bladder is overly full and leaks urine. You may feel as though you need to empty your bladder but cannot.

Urinary Tract Infection (UTI)

Urinary tract infections are usually caused by bacteria from the bowel that live on the skin near the rectum or near the vagina. Because the openings of the bowel, vagina and urethra are close together, it's easy for the bacteria to spread from the bowel to the urethra and travel up the urinary tract into the bladder, sometimes into the kidneys.

Normal urine is sterile, containing fluid, salts and waste products, but not bacteria. Infections can come from a variety of bacteria that normally live in the digestive system, but infections can also be caused by sexually transmitted microorganisms such as chlamydia and mycoplasma.

Infection can occur when the bacteria cling to the opening of the urethra and multiply, producing an infection of the urethra, called urethritis. Infection can also occur when the bacteria get into the bladder, causing cystitis, or a bladder infection. If the problem is not treated, the infection can continue spreading up the urinary tract, causing infection in the kidneys, called pyelonephritis. A kidney infection that is not treated can result in the kidneys being unable to drain urine, permitting the bacteria to enter the bloodstream, which can cause a life-threatening infection.

The first sign of a UTI is usually a strong urge to urinate. As you release urine, you feel a painful burning sensation, and little urine is eliminated. The urge to urinate returns quickly, and urination may be hard to control. You may have urine leakage during sleep. You may also have soreness in your lower abdomen, in your back, or in the sides of your body. Your urine may look cloudy or have a reddish tinge from blood. It may smell foul or strong. You also may feel tired, shaky and washed out. If the infection has spread to the kidneys, you may have fever, chills, nausea, vomiting and back pain, in addition to the frequent urge to urinate and painful urination.

Vesicoureteral Reflux (VUR)

When urine flows backward from the bladder into the ureters, the condition is called vesicoureteral reflux (VUR). It is most often diagnosed in childhood. If your child develops a urinary tract infection, he or she should be evaluated for VUR because the condition is found in about one-third of children with a UTI .

Primary VUR arises when a child is born with an impaired valve where the ureter joins the bladder. The valve fails to close fully, causing urine to back up from the bladder into the ureters and kidneys. The condition may improve over time as the ureter grows and valve function improves.

Secondary VUR arises due to a blockage in the urinary tract, often the result of an infection that causes the ureter to swell. Again, the result is a backflow of urine into the kidneys.

The leading symptom of VUR is infection. Other symptoms may arise as a child gets older, including high blood pressure, proteinuria and kidney failure.

Diagnosing VUR may involve a voiding cystourethrogram, a test that provides an image of the urinary system to determine if a defect in the urinary tract is causing VUR and infection. Other tests may include a kidney and bladder ultrasound; an intravenous pyelogram (IVP), which involves injecting a liquid that can be seen on x-rays to highlight any obstructions in the kidney or bladder; or nuclear scans, tests that use radioactive material injected into a vein to reveal how well the kidneys and bladder are functioning.

The goal of VUR treatment is to prevent kidney damage. An infection should be treated immediately with antibiotics to prevent it from moving into the kidneys. Antibiotics can also help correct reflux caused by an infection. Sometimes surgery is necessary to repair a physical defect that causes VUR.

Urinary Retention

Sometimes the bladder fails to empty fully, leading to retained urine. Acute urinary retention results in a sudden inability to urinate, accompanied by pain and discomfort. The condition may be caused by a urinary tract obstruction from the prostate gland in men or from pelvic masses in women (fibroid tumors are the most common); stress or neurological factors; infection; and certain medications. Relaxation of the pelvic floor structures resulting in a large bulging cystocele may also result in kinking of the urethra and urinary retention. The cause determines the treatment.

Urinary retention is a relatively common problem after surgery. It occurs as a result of the anesthetic, drugs used for pain control or the type of surgery performed. Chronic urinary retention, by contrast, refers to a persistent condition of urine remaining in the bladder and incomplete emptying. Chronic urinary retention can lead to urinary tract infections.

Evaluation for urinary retention includes a medical history and physical examination (including a prostate examination in men) to find the source of the problem. If an acute nerve problem is suspected, your doctor may order a CT scan or MRI . A urogynecologist or urologist may perform advanced urodynamic testing to help determine the cause of the voiding dysfunction. He or she may also perform a cystoscopic examination.