Urinary Tract Infections Flashcards
Who should be screened and treated for asymptomatic bacteriuria?
Pregnant patients and patients undergoing urologic procedure where mucosal trauma / bleeding is expected
What is the pathophysiology of ascending UTI?
Colonic / fecal flora colonise periurethral area, ascend to bladder and kidney
When is hematogenous (descending) UTI suspected?
When organisms that are not colonic are grown e.g. s. aureus, mycobacteria tuberculosis
Describe the 4 host defense mechanisms against UTI
- Bacteria in the bladder stimulates micturition, increase diuresis and flushes bacteria out
- Antibacterial properties of urine and prostatic secretions
- anti-adherence mechanisms of bladder
- Inflammatory response with PMNs (phagocytosis to control spread)
List the risk factors of UTI
Female (shorter urethra), sexual intercourse, abnormalities of the urinary tract, neurologic dysfunctions, anticholinergic drugs (urinary retention), catheterisation, diabetes, pregnancy, use of spermicides and diaphragms, previous UTI, family history of UTI
Provide 6 non-pharmacological counselling points to prevent UTI
- drink fluids
- urinate frequently
- pee after sex
- wipe from front to back
- keep area dry, wear cotton underwear
- find other forms of birth control, x diaphragms and spermicide use
What are the symptoms of pyelonephritis compared to cystitis?
flank pain, general systemic symptoms, costovertebral tenderness
What does positive nitrites in urine dipstick test indicate?
at least 10^5 gram negative bacteria present per mL of urine
What does positive leukocyte esterase in urine dipstick test indicate?
Highly correlated with significant pyuria (WBC in urine)
What does the presence of WBC casts (masses of cells and proteins) in UFEME indicate?
upper UTI
When may urine cultures be necessary?
Pregnant, recurrent UTI, catheter-associated, pyelonephritis, men
What are the likely pathogens in uncomplicated / community-acquired UTI?
E. coli, S. saprophyticus
Enterococcus, Klebsiella, proteus
When is a UTI considered uncomplicated?
UTI in premenopausal, non-pregnant woman with no history suggesting abnormal urinary tract
What are the likely pathogens in complicated / healthcare-associated UTI?
e. coli
enterococci
klebsiella, proteus, enterobacter, pseudomonas
(more resistant organisms, possibility of ESBL producing bact)
What are the 3 first-line regimens for empiric treatment of uncomplicated cystitis in women?
- PO Bactrim 960mg BD x3d
- PO Nitrofurantoin 50mg QDS x5d
- PO Fosfomycin 3g single dose