Urinary Tract Infection Flashcards
How does a urinary tract infection occur?
Results from pathogens invading one or more urinary tract structures.
Describe urinary tract infection.
- Urinary Tract Infections (UTIs) are usually bacterial and most often caused by E. Coli bacteria.
- Can be caused by a fungus or parasite but that usually occurs in:
– Immunosuppression
– Diabetes
– Multiple courses of antibiotic therapy
– Kidney function problems
What are the different types of urinary infections?
Pyelonephritis
- Infection of the kidney or renal pelvis
Cystitis
- Infection of the bladder
Urethritis
- Infection of the urethra
Urosepsis
- a UTI that has spread systemically and can be life-threatening
What part of the urinary tract is considered sterile?
The area above the urethra
What mechanisms keep the area above the urethra sterile?
- Normal voiding with complete emptying of the bladder
- Uretovesical junction competence.
- Ureteral peristaltic activity that propels urine toward the bladder.
How is the urinary tract kept sterile?
- Antibacterial characteristics of urine
- Acidic pH of urine (less than 6.0)
- High urea concentration
- Glycoproteins that interfere with bacterial growth
- Please note: A change in any of these defenses will increase the risk of developing a UTI.
How does the urinary tract defend itself?
- Washout phenomenon – bacteria are removed from the bladder and urethra when voiding.
- Bladder lining – assists in providing a barrier against bacterial invasion.
- Body’s immune responses
– Peristaltic movement within the ureters.
– Normal flora in peri-urethral area in women consists of Lactobacillus which is a defense mechanism.
> Estrogen- protects the peri-urethral flora
– Normal flora in the prostatic secretions
– Acidic environment
Describe bacterial entry.
- Ascending Infection
- Hematogenous Spread
- Lymphatogenous Spread
- Direct Extension
What is the most common cause of a UTI?
Infection acquired through the urethra
What increases the risk of UTI in women?
Short urethra and rectal bacteria
Why is sexual intercourse a major precipitating factor of UTI?
- Sexual intercourse allows “milking” of bacteria from the vagina and perineum and may cause minor urethral trauma that predisposes women to urinary tract infections.
- Can occur as quickly as 12 hours after intercourse.
What can cause an ascending infection?
- Urologic Instrumentation
- Catheterization
- Cystoscopic examination
- Allows bacteria that are normally present at the opening of the urethra to enter into the urethra or bladder
How does a Hematogenous infection occur?
- Blood-borne bacteria secondarily invade the kidneys, ureters, or bladder from elsewhere in the body.
- There must be a prior injury to the urinary tract, such as obstruction of the ureter, damage caused by stones, or renal scars, for a kidney infection to occur via this route.
What can a hematogenous infection occur with?
- Tuberculosis
- Renal abscesses
- Perinephric abscesses.
How common is a lymphatogenous infection?
rare
How does a lymphatogenous infection occur?
Bacteria travel through rectal & colonic lymphatics to:
- Prostate and bladder in males
- Thru periuterine lymphatics to the female genitourinary tract.
How does a direct extension injection occur?
from another organ
What does a direct extension injection occur with?
- Intraperitoneal abscesses, especially those associated with inflammatory bowel disease,
- Pelvic inflammatory disease
- Paravesical abscesses
- Genitourinary tract fistulas.
What do most urinary tract infections occur from?
- E. Coli
- Candida Albicans- most often with indwelling catheters
- Pseudomonas
- Klebsiella
- Proteus
- Backflow of urine
- Urinary stasis
- Impaired bladder emptying
- neurogenic disorders
Who is at risk for a urinary tract infection?
- People who have mobility challenges
- Older adults
- Immunosuppressed – disease or drugs
- Diabetes
List the clinical manifestations of a lower UTI.
- Frequency (more than q 2 hours)
- Urgency
- Dysuria (burning on urination)
- Cloudy or foul-smelling urine
- Suprapubic discomfort or pressure
- Hematuria (red blood cells in the urine)
- Pyuria (white blood cells in the urine)
List the clinical manifestations of an upper UTI.
- Fever
- Flank pain
- Costovertebral angle tenderness
- Nausea
- Vomiting
What are some minor symptoms of a UTI?
- Asymptomatic
- Fatigue
- Anorexia
List some clinical manifestations of a UTI in older adults.
- non-localized abdominal discomfort
- cognitive impairment
- less likely to experience a fever
