Week 8: UTI's Flashcards
Lecture 14
Cystitis
Infection in bladder
Pyelonephritis
Infection in kidney- fever, flank tenderness (upper UTI)
Urethritis
Inflammation of urethra
Seeding of the urinary tract by bacteria
Bacteria from rectum appear in bladder and urethra, the emptying of the bladder flushes out bacteria, then the bladder and urethra are free of bacteria
Pathogenesis of UTI
Perineal region to the urethra
Normal flora: lactobacillus, staphylococcus, corynebacterium, enterococcus
Cathers and UTI
Prone to biofilm formation which lead to continuous seeding and urine becomes contaminated from bacteria in catheter
What can untreated UTIs lead to?
Urosepsis
List some symptoms consistent with a UTI infection?
Urgency, frequency, pyuria, pain with urination, occasional fevers
What type of UTI is associated with fevers?
Upper urinary tract infections
How much bacteria constitutes a UTI?
10-100x10^6/ml
What can make a Dx for a UTI difficult?
Hydration, time urine is in bladder, antibiotic use, collection method, storage conditions
Dipstick
Rapid tests to test for pyuria (cells) and nitriles (bacteria metabolize nitrate to nitrites)
Why are UTI more common in women than men?
Shorter urethra
Who can complicated UTI present in?
All sexes and age groups an are commonly associated with structural or functional urinary tract abnormalities
What are some risk factors associated with UTI’s?
Male or female, altered vaginal flora, sexual intercourse, diaphragm/spermicide, mechanical obstruction, catheters, age (prostate)
Asymptomatic bacteriuria- is this an infection?
NO
Define asymptomatic bacteriuria?
Colonization, treatment indicated only in pregnancy or for those undergoing urinary instrumentation
What can we sometimes confuse asymptomatic bacteriuria for?
UTI
How would we treat asymptomatic bacteriuria?
trimethoprim sulfamethoxazole, ciprofloxacin and ampicillin
Contamination vs. UTI?
Hard to get urine sample from indwelling catheter and cannot use sample from bag (not a clean midstream). use an in and out catheter.
Treatment and prevention of UTI?
Cranberry juice (inconsistent results on this), frequent urination, increased risk after first infection of relapse
How do we treat UTI?
Typically high dose antibiotics X3 days in UNCOMPLICATED infections
What are some diagnostic challenges for UTIs?
urine is considered sterile but it can be colonized with bacteria without an inflammatory response; not need to be treated. BUT the organisms that cause UTIs are also the same as those seen in AB. Rapid tests don’t work.
Are most uncomplicated UTI’s mono- or poly- microbial ?
Mono.
Urine dipstick
Nitrate levels are specific for gram negatives that convert nitrate to nitrite
Leukocyte esterase as well
Leukocyte esterase
Produced by neutrophils
When can bacteria in urine double?
Every 20’
How long can you let urine “sit out” or how long must you refrigerate it?
2 hrs or 24 hrs in fridge
What is the BEST way to get a clean urine sample?
In and out catheter or suprapubic aspirate (this is not practical)
What is vaginitis?
Increased vaginal discharge, painful intercourse, and pain upon urination
What are the 3 types of vaginitis
Bacterial vaginosis
Candidiasis/yeast
Trichomonas vaginitis
What can give you a pseuodomans UTI?
Medical devices, immunosuppressants, UT abnormalities, antibiotic exposure
