Urinary Tract Infections Quiz

Study Notes

UTIs are the presence of pathogenic microorganisms in the genitourinary tract, with associated signs and symptoms of infection.
UTIs present as a variety of syndromes, based on location in the urinary tract, including acute cystitis, pyelonephritis, and prostatitis.
Pathogens can invade urinary tract tissues and adjacent structures, or be limited to bacterial growth in the urine, sometimes without symptoms.
UTIs can range from asymptomatic bacteriuria to pyelonephritis with bacteremia or sepsis.
Bacteria often colonize the female urethra due to its shorter length and proximity to the perirectal area.
Pyelonephritis (infection of one or both kidneys) is sometimes classified as a subset of complicated UTIs if caused by functional/structural abnormalities.
Common bacterial pathogens causing complicated UTIs include Enterobacteriaceae and other Gram-negative bacteria, and Gram-positive bacteria like enterococci.
Escherichia coli is the most common cause of uncomplicated UTIs.
UTIs account for 8 million patient visits annually.
Approximately one in three females will have a UTI by age 24.
UTIs in males are less common until age 65.

Men:
- Intercourse with an infected woman
- Prostate hyperplasia
Women:
- Sexual intercourse
- Lack of voiding after intercourse
- Use of a diaphragm contraceptive
- Pregnancy
Both men and women:
- Diabetes Mellitus (DM)
- Urologic instrumentation
- Renal transplantation
- Neurogenic bladder
- Urinary tract obstruction

Lower UTI (Cystitis):
- Dysuria, urgency, frequency, nocturia, suprapubic heaviness, suprapubic tenderness on examination, and gross hematuria.
Upper UTI (Pyelonephritis):
- Flank pain, fever, nausea, vomiting, costovertebral tenderness, malaise.
Laboratory Tests:
- Bacteriuria
- Pyuria (WBC count >10/mm3)
- Nitrite positive urine (with nitrite reducers)
- Leukocyte esterase positive urine
- Antibody-coated bacteria (upper UTI)

Bacteriuria (bacteria in the urine) doesn't always indicate infection.
Quantitative criteria are used to diagnose significant bacteriuria, identifying the amount of bacteria potentially signifying infection.
Asymptomatic bacteriuria (ASB) is significant bacteriuria (>105 bacteria/mL of urine) in two consecutive urine cultures, in the absence of symptoms, commonly seen in those above 65 years of age.
Symptomatic bacteriuria or acute urethral syndrome involves frequency and dysuria without significant bacteriuria; sometimes associated with Chlamydia infections.

Goals: Eradicate the organism, prevent/treat consequences, prevent recurrence.
Reinfection: Recurrence due to a new organism.
Relapse: Recurrence due to the same organism (suggests persistent infectious source).
Management: Initial evaluation, selection of antibacterial agent, duration of therapy, and follow-up evaluation.
Considerations include antibiotic susceptibility, side effects, cost, previous antimicrobial exposure, and treatment convenience.
Empirical antibiotic therapy, considering local resistance patterns to minimize treatment failure chances.
Antimicrobial treatment should be well-tolerated, narrow spectrum, patient-friendly, reach the infection site effectively, and be orally bioavailable.
Adjunctive therapies (e.g., phenazopyridine for severe dysuria).

Antimicrobial therapy (empirical) is the cornerstone of treatment in UTIs.
Ideal characteristics include well-tolerated, narrow spectrum, patient-friendly, effective site-of-infection concentration, and good oral bioavailability.

Specific treatments (antibiotics) and durations are presented for various diagnoses and populations (e.g. acute uncomplicated cystitis, acute uncomplicated pyelonephritis, pregnancy).

Pregnancy increases UTI risk due to physiologic changes (hormonal, mechanical).
Increased risk of acute pyelonephritis, preterm birth, and stillbirth.
Pregnant women should be screened for bacteriuria (urine culture).
Appropriate, and sometimes different antibiotic treatments are discussed for pregnant individuals.

Indwelling catheters are common and associated with UTIs via catheterization or bacterial motility.
Screening, prophylactic and treatment of UTIs in catheterization patients is discussed

Reinfection is sometimes associated with sexual intercourse.
Treatment with single doses of trimethoprim-sulfamethoxazole or nitrofurantoin after sexual activity may help prevent reinfection.

Asymptomatic and symptomatic UTIs are less common in men than women due to anatomical differences.
Most men with UTI should be treated as a complicated infection with possible complications.
Treatment and considerations are discussed for specific cases, including but not limited to males with complicated infections.