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Flashcards in UTI's Deck (19):

Adult UTI defined by

dysuria, frequency, and urgency with >100 organisms/mL by semiquantitative urine culture; common in ADULT WOMEN


Uropathogenic E coli causes; almost all others are;

75-90% UTI's; OPPORTUNISTIC and can be Enterbacteriaceae, enterococcus, STIs, others: the opportunistic Enterobacteriaceae and Enterococci are less pathogenic than E coli but just as drug-resistant;

can remove/switch catheters


Pediatric UTI is

tenderness in the lower abdo with inadequate urine flow and >50000 IUs/mL (see dribble, poor stream, straining)


Enterobacteriaceae are

gamma-proterobacteria (gram neg rods) including E coli, shigella, salmonella, and two groups of opportunistic pathogens that can cause UTIs: Kleb/Enterobacter/Serratia and Proteus/Providencia/Morganella


Enterobacteriaceae are promiscuous to

incorporating foreign DNA leading to rapid acquisition of virulence factors and antibiotic resistance; they are gram neg rods, facultative anaerobes, mostly normal GI flora


Typical UTI is

sexually active woman colonized in GI with uropathogenic E coli; think annoying recurrent infections that can be dangerous if untreated (obstruction leads to sepsis)


Uropathogenic E coli use

major virulence factor P fimbrae to attach to uroepithelial cells, working their way gradually up the tract (diabetes is a risk factor);

gamma-proteobaceria, straight gram neg rod, facultative anaerobe, lactose fermenter, can be mobile or nonmobile;

leading cause of NOSOCOMIAL bacteremia


Atypical UTIs are

opportunists: sequals of urinary tract procedures/catheters, diabetes, or sepsis



Kleb/Enterobacter/serratia: in addition to UTIs,

encapsulated K (to defend against phagocytosis and complement) can cause dangerous hemorrhagic pneumonia in alcoholic men (diabetes, advanced age), E can become "panresistant" (but rarely causes disease in previously-healthy; has exotoxin called cytolysin) and S can cause endocarditis in heroin addicts; all can be dangerous nosocomial infections and antibiotic-resistant "ICU bugs";

gram neg rods, Ab resistance problematic, think men, elderly, neonates at greatest risk (MEN); opportunistic nosocomial infections;

K pneumoniae: currant jelly sputum; think 100% mortality with alcoholics and bacteremia


Proteus/Providencia/Morganella: cause

UTIs with struvite stones using urease virulence factor (raises pH of urine and bladder); attach with fimbrae;

make urease, DON'T ferment lactose, gram neg rods; increases prevalence of antibiotic resistance;

can see urinary tract obstruction leads to septicemia if untreated; proteus can lead to pneumonia/wound infection, providentia to gastroenteritis, morganella the rarest


Enterococci are NOT

enterobacteriaceae; more like strep (gram pos cocci in chains; grow in high salt) BUT drug resistant; VREs are a growing nosocomial problem and cause UTIs, endocarditis, contribute to polymicrobial intra-abdo infections; PUEG

can pass resistance genes to S aureus;

risk factors include recent broad-spec antibiotics, like third-gen cephalosporins



uncomplicated UTI, treat with ampicillin (lower tract only)



kidney infection, third-gen or combined drugs and antibiotic sens testing (see fever and flank pain from upward spread of infection)


Cranberry juice window:

pts with recurring infections learning to recognize very early symptoms, before antibiotics are indicated; b/c microbial numbers are so low at this stage, use home remedies (rest, nutrition, hydration, family visits, physical therapy, prayer and meditation, anti-inflamms, expectorants, analgesics, nasal irrigation, stress relief, NOT overdose of vitamins or refusing med care) that could be effective; counsel pt to try one but ALWAYS present to MD if symptoms worsen


UTI diagnosis:

Besides the symptoms, take urine samples for semiquantitative culture (streak out on agar plate for colonies)


Ecoli treatment:

Cystitis: trimeth-sulfa or ampicillin;
polynephritis/sepsis: third-gene cephalosporin


K/E/S group diagnosis; treatment; prevention:

1. Culture and gram stain
2. Can do semiquantitative urine culture
3. K pneumoniae gives mucoid appearance on agar
4. S marcescens makes red-pigmented colonies;

think aminoglycosides and cephalosprin (except enterobacter);

remove/relocate catheters and minimize hospital stays; scrubdowns in ICU


P/P/M diagnosis; treat and prevent:

1. UTI, flank pain
2. beta-lactam Ab therapy history
3. urine culture
4. maybe enzyme immunoassay;
get rid of colonized catheters, and also try aminoglycosides, trimeth/sulfa


Enterococcus treatment:

1. swap out IVs, catheters
2. polymicrobial infections: treat principal pathogen
3. ampicillin; if allergic vancomycin, VRE nitrofurantoin; endocarditis ampicillin/vancomycin and gentamicin/streptomycin/ceftriaxone