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Urinary Tract Infection
Introduction
Urinary tract infections are a serious health problem affecting millions of people each year.
Infections of the urinary tract are common—only respiratory infections occur more often. Each year, urinary
tract infections (UTIs) account for about 9.6 million doctor visits. Women are especially prone to UTIs for
reasons that are poorly understood. One woman in five develops a UTI during her lifetime.
The urinary system consists of the kidneys, uterus, bladder, and urethra.
The key elements in the system are the kidneys, a pair of purplish-brown organs located below the ribs
toward the middle of the back. The kidneys remove liquid waste from the blood in the form of urine, keep a
stable balance of salts and other substances in the blood, and produce a hormone that aids the formation of
red blood cells. Narrow tubes called ureters carry urine from the kidneys to the bladder, a triangle-shaped
chamber in the lower abdomen. Urine is stored in the bladder and emptied through the urethra.
The average adult passes about a quart and a half of urine each day. The amount of urine varies, depending
on the fluids and foods a person consumes. The volume formed at night is about half that formed in the
daytime.
Detailed Description
The urinary tract is divided into a lower part and an upper part.
The upper part of the tract consists of the kidneys, which make urine from the blood that circulates through
its filtering and collecting systems, and tubes called ureters that carry urine to the bladder. An infection of
the upper tract causes more severe illness than an infection of the lower tract, but it is also less frequent.
The lower part is made up of the urethra, a 1-1/2- to 2-inch-long tube that urine passes through on its way
out of the body, and the bladder, which stores urine.
Most infections occur in the lower part and although they are very uncomfortable, they are seldom serious.
The organisms that cause infection usually enter the urinary tract by one of two ways: at the end of the
urinary tract (the urethra) or at the beginning (the kidneys).
Most often, infectious organisms enter the urinary tract through the urethra by going in the opening at the tip
of a man's penis or the opening of a woman's urethra (or within the vulva).
*More than 85% of UTI’s are caused by bacteria from a person's own intestine or vaginal infections.
*Sometimes, the infection enters the urinary tract through the bloodstream, in these cases usually directly to
the kidneys.
Urinary tract infections cause pain and burning during urination; they also make you feel the urgent need to
urinate often.
Women are more prone to UTI’s because of their anatomy: a woman's urethra is shorter than the man's and is
very close to the vagina and rectum.
Normal Flora of the Urinary and Reproductive System
Normal urine is sterile in the urinary bladder and the organs of the upper urinary tract. The urethra, how
ever does contain a normal resident flora that includes Streptococcus, Bacteroides, Mycobacterium, Neisseria,
and a few Enterobacteria. Urine becomes contaminated with members of the flora during its passage through
the urithra.
What Are the Causes of UTI?
Normal urine is sterile. It contains fluids, salts, and waste products, but it is free of bacteria, viruses, and
fungi. An infection occurs when microorganisms, usually bacteria from the digestive tract, cling to the
opening of the urethra and begin to multiply. Most infections arise from one type of bacteria, Escherichia coli
(E. coli), which normally live in the colon.
In most cases, bacteria first begin growing in the urethra. An infection limited to the urethra is called
urethritis. From there bacteria often move on to the bladder, causing a bladder infection (cystitis). If the
infection is not treated promptly, bacteria may then go up the ureters to infect the kidneys (pyelonephritis).
The kidney are some times affected by systemic bacterial disease, such as typhoid fever and Leptospirosis (is
a primary disease of domestic or wild animals but can be passed to humans and cause some time sever kidney
or liver disease). Also bacteria can cause another inflammation in the kidney called Glomerullonephritis
(Bright’s disease) is an inflammation of the glomeruli in the kidneys.
Microorganisms called Chlamydia and Mycoplasma may also cause UTI’s in both men and women, but these
infections tend to remain limited to the urethra and reproductive system. Unlike E. coli, Chlamydia and
Mycoplasma may be sexually transmitted, and infections require treatment of both partners.
The urinary system is structured in a way that helps ward off infection. The ureters and bladder normally
prevent urine from backing up toward the kidneys, and the flow of urine from the bladder helps wash
bacteria out of the body. In men, the prostate gland produces secretions that slow bacterial growth. In both
sexes, immune defenses also prevent infection. Despite these safeguards, though, infections still occur.
Synonyms
• Bladder infection (cystitis)
• Infection of the urethra (urethritis)
• Infection of the ureters (ureteritis)
• Kidney infection (pyelonephritis)
• Systemic bacterial infection to the kidney (Leptospirosis)
How Common Are Urinary Tract Infections?
UTI’s are more common in male than female newborns, but by age 1, they are about 10 times more common
in girls. However, the great increase begins after initiating sexual intercourse. Therefore, UTI’s.
Symptoms and Diagnosis
Signs and symptoms of urinary tract infections (UTI’s) include:
• Urgent need to urinate
• Increased urinary frequency (especially at night)
• Pain or burning during urination (dysuria)
• Chills
• Nausea
• Vomiting
• Soreness in the lower abdomen, lower back, and/or sides
• Cloudy urine
• Blood in urine (this occurs in about 30% of people with UTI’s)
• Pain during sex
• But keep in mind that people whose nerves supply to the bladder is malfunctioning (neurogenic
bladder), people who have had a catheter left continuously in the bladder, and older people may not show
any symptoms.
Introduction
Urinary tract infections are a serious health problem affecting millions of people each year.
Infections of the urinary tract are common—only respiratory infections occur more often. Each year, urinary
tract infections (UTIs) account for about 9.6 million doctor visits. Women are especially prone to UTIs for
reasons that are poorly understood. One woman in five develops a UTI during her lifetime.
The urinary system consists of the kidneys, uterus, bladder, and urethra.
The key elements in the system are the kidneys, a pair of purplish-brown organs located below the ribs
toward the middle of the back. The kidneys remove liquid waste from the blood in the form of urine, keep a
stable balance of salts and other substances in the blood, and produce a hormone that aids the formation of
red blood cells. Narrow tubes called ureters carry urine from the kidneys to the bladder, a triangle-shaped
chamber in the lower abdomen. Urine is stored in the bladder and emptied through the urethra.
The average adult passes about a quart and a half of urine each day. The amount of urine varies, depending
on the fluids and foods a person consumes. The volume formed at night is about half that formed in the
daytime.
Detailed Description
The urinary tract is divided into a lower part and an upper part.
The upper part of the tract consists of the kidneys, which make urine from the blood that circulates through
its filtering and collecting systems, and tubes called ureters that carry urine to the bladder. An infection of
the upper tract causes more severe illness than an infection of the lower tract, but it is also less frequent.
The lower part is made up of the urethra, a 1-1/2- to 2-inch-long tube that urine passes through on its way
out of the body, and the bladder, which stores urine.
Most infections occur in the lower part and although they are very uncomfortable, they are seldom serious.
The organisms that cause infection usually enter the urinary tract by one of two ways: at the end of the
urinary tract (the urethra) or at the beginning (the kidneys).
Most often, infectious organisms enter the urinary tract through the urethra by going in the opening at the tip
of a man's penis or the opening of a woman's urethra (or within the vulva).
*More than 85% of UTI’s are caused by bacteria from a person's own intestine or vaginal infections.
*Sometimes, the infection enters the urinary tract through the bloodstream, in these cases usually directly to
the kidneys.
Urinary tract infections cause pain and burning during urination; they also make you feel the urgent need to
urinate often.
Women are more prone to UTI’s because of their anatomy: a woman's urethra is shorter than the man's and is
very close to the vagina and rectum.
Normal Flora of the Urinary and Reproductive System
Normal urine is sterile in the urinary bladder and the organs of the upper urinary tract. The urethra, how
ever does contain a normal resident flora that includes Streptococcus, Bacteroides, Mycobacterium, Neisseria,
and a few Enterobacteria. Urine becomes contaminated with members of the flora during its passage through
the urithra.
What Are the Causes of UTI?
Normal urine is sterile. It contains fluids, salts, and waste products, but it is free of bacteria, viruses, and
fungi. An infection occurs when microorganisms, usually bacteria from the digestive tract, cling to the
opening of the urethra and begin to multiply. Most infections arise from one type of bacteria, Escherichia coli
(E. coli), which normally live in the colon.
In most cases, bacteria first begin growing in the urethra. An infection limited to the urethra is called
urethritis. From there bacteria often move on to the bladder, causing a bladder infection (cystitis). If the
infection is not treated promptly, bacteria may then go up the ureters to infect the kidneys (pyelonephritis).
The kidney are some times affected by systemic bacterial disease, such as typhoid fever and Leptospirosis (is
a primary disease of domestic or wild animals but can be passed to humans and cause some time sever kidney
or liver disease). Also bacteria can cause another inflammation in the kidney called Glomerullonephritis
(Bright’s disease) is an inflammation of the glomeruli in the kidneys.
Microorganisms called Chlamydia and Mycoplasma may also cause UTI’s in both men and women, but these
infections tend to remain limited to the urethra and reproductive system. Unlike E. coli, Chlamydia and
Mycoplasma may be sexually transmitted, and infections require treatment of both partners.
The urinary system is structured in a way that helps ward off infection. The ureters and bladder normally
prevent urine from backing up toward the kidneys, and the flow of urine from the bladder helps wash
bacteria out of the body. In men, the prostate gland produces secretions that slow bacterial growth. In both
sexes, immune defenses also prevent infection. Despite these safeguards, though, infections still occur.
Synonyms
• Bladder infection (cystitis)
• Infection of the urethra (urethritis)
• Infection of the ureters (ureteritis)
• Kidney infection (pyelonephritis)
• Systemic bacterial infection to the kidney (Leptospirosis)
How Common Are Urinary Tract Infections?
UTI’s are more common in male than female newborns, but by age 1, they are about 10 times more common
in girls. However, the great increase begins after initiating sexual intercourse. Therefore, UTI’s.
Symptoms and Diagnosis
Signs and symptoms of urinary tract infections (UTI’s) include:
• Urgent need to urinate
• Increased urinary frequency (especially at night)
• Pain or burning during urination (dysuria)
• Chills
• Nausea
• Vomiting
• Soreness in the lower abdomen, lower back, and/or sides
• Cloudy urine
• Blood in urine (this occurs in about 30% of people with UTI’s)
• Pain during sex
• But keep in mind that people whose nerves supply to the bladder is malfunctioning (neurogenic
bladder), people who have had a catheter left continuously in the bladder, and older people may not show
any symptoms.
