Urinary Tract Infections Flashcards
coagulase _____ staphylococci is part of the normal microflora of the urethra
coagulase NEGATIVE staphylococci
the proportion of ________ (microorganism family) in the vagina varies with new borns, pre pubescent, pubescent, and menopause
lactobacilli
imbalance in _______ (microorganism) can lead to UTI’s
Describe the biology of this organism
lactobacilli
gram postive rods, NON spore foring
anaerobes, produce lactic acid;
can lead to UTI’s when the pH is ↑
UTI’s with a fever is indicative of _____ (organ) involvement
kidneys (pyelonephritis)
______ (organism) is the most common culprit in the majority of UTI’s
E. coli; especially in uncomplicated UTI
in addition to UTI’s, what are other long term complications of urinary catheterization
- obstruction → bacterial glycocalyx (biofilm formation)
- formation of encrustations and infection stones
- local infections
what are the key virulence factors of UPEC (uropathogenic E. coli)
- Type I pili (cystitis)
- P pili (Pyelonephritis)
α hemolysin, siderophores and pathogenicity islands;
O/K serogroup is used to classify UPEC
O serogroup
UPEC with Type I pili will most likely cause ________ (type UTI)
cystitis
P pilli = pyelonephritis
what are 3 host defenses against UTI’s within the lumen of the bladder?
- anti microbial peptides
- competition with iron sequestering proteins
- tamm horsfall protein which binds to type 1 fimbriated E. coli and prevents it from adhering to the urothelial receptors
Tamm horsfall proteins are found in ________ and its function is ______
found in the lumen of the bladder and binds to type 1 fimbriated E. coli and prevents their adhesion to the bladder epithelium (type P pili E. coli bind to the the renal epithelium and cause pyelonephritis)
post sex cystitis most likely pathogen is _______
staph saprophyticus “honeymoon cystitis”; has urease
it is a coagulase negative staph (another coagulase negative staph is staph epidermidis)
“swarming” colonies on agar is used to describe what pathogen that can cause UTI’s
Proteus mirabilis; motile activity due to flagella
what type of renal stones are likely to be formed due to UTI’s from organisms such as proteus mirabilis?
struvite crystals because they both contain urease which makes the urine more alkaline due to ammonia production
what are some virulence factors of Proteus mirabilis
- protease
- hemolysin
- biofilm formation
- urease production
it is a gram negative facultative anaerobic rod
Proteus mirabilis is found in uncomplicated/complicated UTI’s
complicated
a patient has had a UTI and later develops a renal stone. The stone’s composition is found to be a urine struvite crystal. what is the most likely causal pathogen of his UTI?
proteus mirabilis
a positive leukocyte esterase test is indicative of ______
inflammation because it is released by WBC’s
urine analysis showed ↑ nitrites (due to nitrates being converted to nitrites) what can you conclude from this test?
- E. coli and Proteus miribilis have the ability to convert nitrate → nitrite so most likely a bacterial cause of UTI
what are the three major infections in vaginitis and which one can be transmitted sexually?
- bacterial vaginosis (most common)
- vulvovaginal candidasis
- trichomoniasis (sexually transmitted)
when examining a histolgicla slide of vaginal discharge, you see presence of “clue cells” which are bacteria adhering to periphery of epithelial cells. what is the most likely diagnosis
bacterial vaginosis (clue cell = BV)
the organism typically adhering to the vaginal epithelium is Gardenerella
women with BV is mono/polymicrobial and have fewer/greater than normal vaginal lactobacilli
polymicrobial and have FEWER than normal lactobacilli
bacterial ph _______ is suggest of bacterial vaginosis
pH > 4.5
describe the discharge that can sometimes be present in someone with bacterial vaginosis
homogenous, non viscous, milky white discharge adherent to vaginal walls
what are the 4 diagnostic criteria in the Amsel Criteria?
- vaginal pH > 4.5
- homogeneous, non viscous milky white discharge
- presence of “clue cells”
- positive amine / “whiff” test (fish odor)
ONLY NEED 3 OF THE 4 FOR DIANGOSIS OF BV
Nugent criteria looks at _______
the amount of lactobacilli and if there is presence of mixed flora
normal has nugent score = 0
Candida albicans has pseudohyphae, dimorphic, and has a +/- germ tube test
positive germ tube test
risk factors for women acquiring vaginal candidiasis include pregnancy, _______, _________ or _______
diabetes mellitus, use of broad spectrum antibiotics or corticosteroids
Amsel criteria is used in the diagnosis of _______
bacterial vaginosis
clumpy, cottage cheese, white discharge is indicative of ______
vaginal candidiasis
can also have secondary oral candidiasis
what are the three most common STI’s in the USA
- chlamydia
- gonorrhea
- syphilis
_______ (UTI) presents with suprapubic tenderness
cystitis
gram postive cocci are less common pathogens that can cause which UTI: cystitis or pyelonephritis?
cystitis;
both can be caused by gram negative rods: klebsiella and proteus
drug resistance is a major threat to the impact of which STI?
gonorrhea
