UTI Flashcards
Upper UTI:
pyelonephritis
Lower UTI:
cystitis, urethritis, prostatitis, epididymitis
Prevalence at:
- 0 - 6mths
- 1 - adult
- elderly (age >65)
- 0 - 6mths: male > female
- 1 - adult: female > male
- elderly (age >65): equal
Common organisms for
- Ascending
- Descending
- Ascending: E. coli, Klebsiella pneumoniae, Proteus spp, Staphylococcus saprophyticus
- Descending: Staphylococcus aureus, Mycobacterium tuberculosis
Host Defense Mechanisms against development of UTI
Bacteria stimulates micturition with increased diuresis -> emptying of bladder
Antibacterial properties of urine & prostatic secretion
Anti adherence mechanisms of bladder (bacterial attachment)
Inflammatory response with polymorphonuclear leukocytes (PMNs) -> phagocytosis -> prevent/control spread
Factors in determining development of UTI besides host defense mechanisms
Size of the inoculum: increased with urinary retention/obstruction
Virulence/pathogenicity: bacteria with pili e.g. E. coli resistant to washout or anti-adherence
Risk Factors for UTI
- Females > males: Pregnancy, Use of diaphragms & spermicides
- Sexual intercourse
- Abnormalities of the urinary tract eg prostatic hypertrophy, kidney stones, urethral strictures, vesicoureteral reflux
- Neurologic dysfunctions eg stroke, diabetes, spinal cord injuries
- Anti cholinergic drugs
- Catheterization and other mechanical instrumentation
- Diabetes
- Genetic association (positive family history)
- Previous UTI
Prevention of UTI
- drink lots of fluid
- urinate frequently and when you feel the urge
- urinate shortly after sex
- wear cotton underwear and loose-fitting clothes
- modify birth control (diaphragm, spermicide, unlubricated or spermicidal condoms)
What counts as uncomplicated UTI?
healthy, premenopausal, non-present women without Hx of abnormalities of urinary tract
Symptoms of cystitis
dysuria, urgency, frequency, nocturia, suprapubic heaviness or pain, gross hematuria
Symptoms of pyelonephritis
Systemic: fever >38C, rigors, headache, nausea, vomiting, malaise
Pain: flank, renal punch (costovertebral tenderness), abdominal
Symptoms of UTI in elderly (less urinary symptoms)
- altered mental status (drowsy, less alert)
2. less appetite
Methods of urine collection
- Midstream clean catch
- Catheterization
- Suprapubic bladder aspiration
Objective markers from microscopic examination
Pyuria: WBC >10cells/mm3 (most indicative)
Hematuria: >5/HPF or gross (non-specific)
Gram-stain
WBC casts: masses of cells/proteins in renal tubules -> upper UTI
Common contaminants in UFEME
Yeast (not pathogen)
Squamous epithelial cells (if >5)
What do the dipstick indicators mean? (nitrite and leukocyte esterase)
- Nitrite: gram-neg bacteria (>10^5 bacteria/mL)
- False negative: gram-pos or P. aeruginosa, low urinary pH, frequent voiding/dilute urine - Leukocyte esterase: correlate w/ pyuria
What are healthcare-associated risk factors for healthcare associated or complicated UTI?
- Hospitalization in the last 90 days
- Current hospitalization >2 days
- Residence in nursing home
- Abx use in the last 90 days
- Home infusion therapy