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
What is the recommended duration of treatment for complicated cystitis in women?
7 - 14 days or PO fosfomycin 3g EOD for 3 doses
What are the alternative treatments for uncomplicated cystitis in women?
Beta-lactams x 5-7d
- PO Cefuroxime 250mg BD
- PO Augmentin 625mg BD
Fluoroquinolones x 3d
- PO Ciprofloxacin 250mg BD
- PO Levofloxacin 250mg OD
(FQ not rec due to high S/E and collateral damage)
What are the recommended regimens for community-acquired pyelonephritis in women (non-severely ill)?
FQ
- PO Ciprofloxacin 500mg BD x 7d
- PO Levofloxacin 750mg OD x 5d
PO Bactrim 960mg BD x 10-14d
Beta-lactams x 10-14d
- PO Cefuroxime 250-500mg BD
- PO Augmentin 625mg TDS
What are the recommended regimens for community-acquired pyelonephritis in women (severely ill)?
IV regimen (switch to PO when possible)
Ciprofloxacin 400mg BD OR Amox-clav 1.2g TDS OR Cefazolin 1g Q8H +/- Gentamicin 5mg/Kg
What antibiotics should not be used in pyelonephritis?
Nitrofurantoin and Fosfomycin (does not go to kidney)
What is the recommended treatment duration for cystitis in men with no concern for prostatitis?
x 10 - 14d with same drugs as cystitis in women
What is the recommended regimen for UTI in men with concern for prostatitis?
PO Ciprofloxacin 500mg BD x 10-14d
PO Bactrim 960mg BD x 10-14d
What are healthcare-associated risk factors for UTI?
recent hospitalisation in last 6m, use of antimicrobials, indwelling catheter, invasive urological procedure in last 6m
What is the definition of nosocomial UTI?
Onset >48H after admission
What are the recommended treatment regimens for nosocomial / healthcare-associated UTI?
Possibility of pseudomonas and ESBL, use broad-spectrum beta-lactam
- IV Cefepime 2g Q12H +/- amikacin 15mg/kg/day
- IV Meropenem 1g Q8H or IV Imipenem 500mg Q6H
For less sick patients
- PO Ciprofloxacin 500mg BD
- PO Levofloxacin 750mg OD
Duration x 10-14d
What antibiotics should be avoided in pregnant women with UTI?
Fluoroquinolones, Aminoglycosides, Bactrim (1st and 3rd trimester), Nitrofurantoin (at term)
What is the duration for treatment of ASB and cystitis in pregnant women?
x 4-7d
What is the duration for treatment of pyelonephritis in pregnant women?
x 14d
What constitutes Catheter-associated UTI?
presence of symptoms or signs compatible with UTI with no other identified source of infection along with 10^3 cfu/mL of ≥1 bacterial species in a single catheter urine specimen in patients with indwelling urethral, indwelling suprapubic, or intermittent catheterization or in a midstream voided urine specimen from a patient whose catheter has been removed within the previous 48h
What is the duration for treatment for catheter-associated UTI?
7d with prompt resolution, 10-14d in delayed response
What are the recommended regimens for catheter-associated UTI?
- IV Meropenem 1g Q8H or IV Imipenem 500mg Q6H
- IV Cefepime 2g Q12H +/- Amikacin 15mg.kg (single dose / daily)
- PO/IV Levofloxacin 750mg OD x 5d (mild)
- PO Bactrim 960mg BD x 3d (women <= 65, removed catheter, non-upper UTI)
For which patient population is post-treatment culture to document bacteriological clearance of UTI indicated?
Pregnant women
