UTI Flashcards
What are the roles of commensals for UTIs?
Compete for resources with more virulent organisms
Produce their own AMPs
Prime the innate cells
Lower vaginal pH
Which species of commensal is of particular importance?
What is its mechanism?
Lactobacillus – Particularly important in protection of female urinary tract
Decreases vaginal pH via lactic acid production, hydrogen peroxide
Prevents pathogenic bacteria from gaining resource foothold
How are commensals disrupted?
Can be disrupted by excessive cleaning of genitals, frequent douching, use of spermicides
What are the normal defenses of the urinary tract?
Urinary tract are more limited than genital tract
Physical force of urine flow
Exfoliation - Appearance of exfoliated cells in the urine is a sign of UTI
AMPs - Tamm-Horsfall Protein (THP: Produced in the Loop of Henle)
Typically innate and adaptive leukocytes are absent from lower urinary tract during health (exception is urethra)
What can ruin the defensive role of physical force?
Obstruction will ruin this defense
Ureterovesical junction acts as a one-way valve to prevent urine from backing up towards the kidneys
Transitional epithelium to accommodate bladder needs
What are the risk factors of UTI?
Women - Shorter urethra
60% of women will develop a UTI
40% of nosocomial infections are UTIs
40% of gram neg bacteremias/year in hospital setting start as UTIs
What is the difference between ascending and descending UTIs?
Ascending – Infectious agent moves up to the kidneys from urethra (more common)
Descending – Due to hematogenous spread (rare)
What is a complicated UTI?
What is associated with it?
Associated with structural or functional abnormality of the GU tract
Presence of a comorbidity – Increases the risk of acquiring an infection or of falling therapy
More prone to become disseminated resulting in sepsis and even death
GU abnormality: Obstruction, stasis, vesicouretral reflux, foreign body, neurogenic bladder with high pressures
Immunocompromised/unhealthy host: DM, transplant patients, chronic steroids
MDR bacteria
What is an uncomplicated UTI?
What is it associated with?
“Simple”
Healthy patient with normal urinary tract
Young to middle aged female
Often triggered by sex
What is the body response to UTI?
Exfoiliation
Neutrophil recruitment
Bladder inflammation is a consequence
Painful urination, lower abdomen discomfort, low-grade fever, pelvic pressure, frequent urination
Diagnosed by presence of leukocytes in urine
What factors determine UTI efficacy?
Most commonly diagnosed using a “dipstick”: Measures several aspects of urine chemistry
Antibiotics are most common treatment for UTI
Coital prophylaxis – for individuals who frequently develop UTI post-coitus
Ability to UPEC to reside in calculi is a cause of recurrent UTI
For complicated UTIs: Whether an underlying anatomical or functional issue is resolved or not
What is cystitis?
What sx are associated with it?
Bladder inflammation
Dysuria
Urinary frequency
Urinary urgency
Suprapubic pain/discomfort/pressure
Cloudy/smelly urine
Hematuria: Gross(more concerning, cannot necessarily attribute it to UTI) or Microscopic
What symptoms are associated with pyelonephritis?
Flank/black pain
High fever, chills
Headache
Nausea/vomiting
Maybe septic shock
+/- Cystitis Symptoms
What does the chemical strip analysis screen for?
Hematuria, pus, bacteria, pH, specific gravity, protein, glucose
What uropathogens are responsible for uncomplicated UTIs?
E. coli (80%)
S. Sapropphyticus
Enterobacteriaceae
Klebsiella, enterobacter, proteus
Salmonella, shigella
Gram positives
S. aureus
GBBS
Enterococci
