LESSON 3
URINARY SYSTEM DISEASES/DISORDERS
Section I. URINARY TRACT INFECTIONS
3-1.
INTRODUCTION
More than 8 million Americans are affected by urinary system related health
problems, which means you may deal with many patients with urinary system
complaints. The urinary system plays a major part in the fluid and electrolyte balance of
the body and with the respiratory system is important in maintaining the blood pH. It is
understandable, therefore, that a problem with the urinary system can have serious
health consequences.
3-2.
ETIOLOGY OF URINARY TRACT INFECTIONS
a. Infecting Microorganisms. The cause of urinary tract infections (UTI) can
be traced to the presence of infectious microorganisms located anywhere between the
kidneys and the urethral opening. The common pathogens are the gram-negative
bacilli, often found in the colon, especially E. coli, klebsiella, and proteus.
Microorganisms acquire access to the kidneys by ascension from the lower urinary tract
beginning at the urethra. Bacterial infections of the lower urinary tract occur about 10
times more frequently in females than in males. A common cause of urinary tract
infection in females is an improper wiping technique.
b. Predisposing Factors. Factors which predispose an individual to UTI
(1) Sex of the individual. Urinary tract infections are common in females of all ages
because the female urethra is short. Additionally, large numbers of pyogenic bacteria
(pus-producing bacteria) inhabit the vaginal vestibule. Urinary tract infections are rare
among males less than 50 years old because the male urethra is enclosed in the penis.
Ascending UTI infections frequently occur after intercourse.
(2) Urinary stasis. Urinary stasis is the stoppage of the flow or discharge of
urine. This condition may be caused by stones, stricture (an abnormal narrowing of a
tubular structure), prostatic enlargement, tumor, or developmental abnormalities.
Urinary stasis may occur at any level of the urinary tract. The statis of urine from any
cause predisposes toward UTI. About 95 percent of people with catheters for three
days develop urinary tract infections.
studies, and therapeutic procedures (such as bladder irrigations) are also causes of
urinary tract infections.
MD0579
3-3