UTIs Flashcards
What is the most common outpatient and hospital acquired infection?
UTIs
What are examples of conditions caused by UTIs?
urethritis
cystitis
prostatitis
pyelonephritis
Which patients commonly experience UTIs?
females, especially of child-bearing age
What are lower UTIs?
infection of the bladder
-cystitis
What are upper UTIs?
infection involving the kidneys
-pyelonephritis
What are uncomplicated UTIs?
no structural or functional abnormalities
Which patients tend to experience uncomplicated UTIs?
premenopausal females of childbearing age (15-45 years), otherwise normal healthy
What are complicated UTIs?
predisposing lesion of the urinary tract-congenital abnormality or distortion of urinary tract,
stone
indwelling catheter
prostatic hypertrophy
obstruction or neurological deficit that interferes with normal urinary flow
True or false: all UTIs in males are considered complicated
true
True or false: children with recurrent UTI should be investigated for urinary tract abnormality
true
How do UTIs develop?
usually develops by ascending route
colonization of vaginal vestibule followed by colonization of urethra
bacteria enter urine, multiply and cause bladder infection
bacteria may spread up ureters to kidney especially if there is vesicoureteral reflux or reduced urethral peristalsis
What is a major determinant for bacterial entry into bladder for some women?
sexual intercourse
What is a rare way that you can develop a UTI? Which organisms are likely the cause of this?
hematogenous
S. aureus, enterococci
Describe the normal defence mechanisms of the urinary tract.
low pH (inhibit and kill bacteria)
extremes in osmolality (inhibit and kill bacteria)
high urea and high organic acid concentrations (inhibit and kill bacteria)
urination washes out of bladder
prostatic secretions in males have antibacterial properties
bladder is coated with urinary mucus which discourages bacterial adherence
What is a probable reason as to why males get UTIs less frequently?
prostatic secretions have antibacterial properties
What are predisposing factors for UTIs?
age
gender
pregnancy
use of spermicides and diaphragms
urinary tract obstruction-including drugs like anticholinergics
incomplete bladder emptying
neurologic dysfunction-stroke, diabetes, spinal cord injury
vesicoureteral reflux
renal disease
Which organisms most frequently cause uncomplicated UTIs?
E.coli (80-90%)
others: Staph saprophyticus, K. pneumoniae, Proteus, Enterococcus
Which organisms frequently cause complicated UTIs?
similar organisms (E.coli-50%) but more varied
-enterobacter
-pseudomonas aeruginosa
-staph aureus
may be more resistant
How can you diagnose UTIs?
urinalysis: bacteruria and pyruria
urine culture: midstream clean-catch method
catherization
suprapubic bladder aspiration
urine dipstick for nitrite (not all bacteria convert nitrates to nitrites)
urine dipstrick for leukocyte esterase (esterase activity of WBC)
What are the normal levels of bacteria and WBCs in urine?
bacteria: 10 to the 8 CFU/L
WBC: >10 WBC/mm3
What is something you should keep in mind with C & S of urine?
recommendation is young healthy women shouldnt get C & S and you should treat empirically
thus, samples are from complicated patients an tx failure so the antibiograms will show resistance but the drugs still work
What is the clinical presentation of lower UTIs (cystitis)?
dysuria
urgency
frequency
nocturia
suprapublic heaviness/pain
gross hematuria
What is the clinical presentation of upper UTIs (pyelonephritis)?
flank pain
fever
nausea
vomiting
malaise
costovertebral tenderness
What are the symptoms of someone who is acutely ill with a UTI?
sepsis
hypotension
renal dysfunction
severe nausea and vomiting
need hospitalization and IV for 48-72hr until pt is afebrile
What should be taken into consideration for UTI treatment?
site of infection (cystitis vs pyelonephritis)
renal function
causative organism
concurrent disease
ability to penetrate urine or kidneys
drug interactions
adverse effects and allergies
cost
What is first line treatment for uncomplicated UTIs in females? List the dosing.
TMP/SMX: 1 DS BID x 3 days
TMP: 100mg BID or 200mg QD x 3 days
Nitrofurantoin: 50-100mg QID or Macrobid 100mg BID x 5 days
alt: cephalexin 250mg QID x 7 days
alt: fosfomycin 3g single dose
What is second line treatment for uncomplicated UTIs in females?
amoxiclav: 500mg TID, 875mg BID x 3-7 days
norfloxacin: 400mg BID x 3 days
ciprofloxacin: 250mg BID or 500mg ER OD x 3 days
Does acute uncomplicated UTIs require antibiotic therapy?
no, self-limiting disease
however, slightly increased risk for complications and its uncomfortable
What is considered to be recurrent UTIs?
2 uncomplicated UTI within 6 months OR
3 or more positive urine cultures in prior 12 months
What is considered to be recurrent UTIs?
2 uncomplicated UTI within 6 months OR
3 or more positive urine cultures in prior 12 months
What is the time frame for reinfection of a UTI?
occurs after 2 weeks (MedSask guidelines use 4 weeks) of completing antibiotic therapy
True or false: UTI reinfection is caused by the same organism as the previous infection
false
caused by a different organism
-if E.coli was original infection, it can be E.coli again but a new
strain
What is the time frame for relapse of a UTI?
2 weeks (2-4wks) of completing antibiotic therapy
True or false: UTI relapse is caused by the original organism
true
What is the treatment of recurrent UTIs?
culture to guide therapy
re-assess for upper tract infection
re-treat for 7-14 days
same antibiotic choices, tailor based on C & S
When can prophylaxis be initiated for UTIs?
short course self treatment at onset of symptoms if less than 3 infections per year
What are the treatment options for prophylaxis of UTIs? What are the dosings?
TMP/SMX: 1 tab or 1/2 DS tab qhs 3x per week or post-coital if
associated with intercourse
TMP: 100mg qhs or post coital
Macrobid: 100mg qhs or post coital
What is a second line option for prophylaxis of UTIs?
FQ: 3x weekly or every other day or post coital
Is cranberry juice good for UTIs?
may be effective for prevention of women or children that get frequent UTIs, NOT FOR TREATMENT
not well studied in all patient populations and it was studied in large amounts
Which people should never use cranberry juice to prevent UTIs?
people who often get kidney stones
What is a therapy that a post-menopausal woman with recurrent cystitis could attempt?
vaginal estrogen
What is the criteria needed that allows a pharmacist to prescribe for UTIs?
not first episode
not pregnantme
uncomplicated
not relapse
What is recommended for any UTI of a man?
urine cultures
What are the drugs for UTIs in males? How long is treatment?
same as females
2 weeks
-evidence that 7 days of SMX/TMP or ciprofloxacin is effective
What are the treatments for pyelonephritis if it is non-obstructive and mild?
TMP/SMX x 14d
TMP x 14d
norfloxacin or ciprofloxacin x 7d
levofloxacin x 5d
amoxicillin/clavulanate x 10-14d
What are the treatments for severe pyelonephritis?
gentamicin 4-7mg/kg q24h +/- ampicillin 1-2g q4-6h
ciprofloxacin 400mg IV q12h
levofloxacin 250-500mg q24
ceftriaxone 1-2g IV q24h (or cefotaxime) +/- gentamicin
What are the causative organisms of bacterial prostatitis?
e. coli (75%)
other gram negatives: K. pneumoniae, P. mirablis, less
frequently P. aeruginosa, enterobacter,
serratia
How is bacterial prostatitis diagnosed?
urine culture
in chronic prostatitis-quantitative localization culture
What is bacterial prostatitis?
inflammation of the prostatic gland and surrounding tissue due to infection
can be caused by reflux of infected urine
What are risk factors for bacterial prostatitis?
indwelling catherization
urethral instrumentation
TURP with infected urine
What are the symptoms of acute bacterial prostatitis?
fever
chills
tenderness/pain
malaise
myalgia
frequency
urgency
nocturia
retention
What are the symptoms of chronic prostatitis?
urinating difficulty
low back pain
perineal and surprapubic pressure
What are the treatments of acute bacterial prostatitis?
TMP/SMX
TMP
norfloxacin
levofloxacin
ciprofloxacin
What are the treatments of severe bacterial prostatitis?
ampicillin or ceftriaxone IV PLUS gentamicin or tobramycin or amikacen
What is the duration of therapy for acute prostatitis?
minimum 2 weeks
total course should be 4 weeks to prevent chronic infection
What are the treatments for chronic prostatitis?
FQs have better cure rate than TMP/SMX
What is the duration of therapy for chronic prostatitis?
4-12 weeks
Why is there a higher rate of UTIs in pregnancy?
dilated renal pelvis and ureters
decreased ureteral peristalsis
reduced bladder tone
What can happen to the newborn of a woman who left a UTI untreated in pregnancy?
prematurity
LBW
stillbirth
What is recommended that all pregnant women do?
routine screening at 12-16 weeks or first prenatal visit and at 28 weeks
What must a women who is positive for UTI do at the end of treatment?
treat for 3-7 days and follow-up culture to document eradication
What is first line treatment of UTIs in pregnancy?
cephalexin 250-500mg QID x 7 days
amoxicillin 500mg TID x 7 days
nitrofurantoin 100mg BID x 5 days
At what point in pregnancy should nitrofurantoin be avoided?
36-42 weeks gestation and during labour
What is second line treatment of UTIs in pregnancy?
TMP/SMX or TMP
-avoid in 1st trimester and in last 6 weeks of pregnancy
When do we treat or screen for asymptomatic UTIs?
pregnancy
pre-operative genitourinary procedures
True or false: there is high elevation of asymptomatic UTIs in elderly
true
At what rate does bacteruria occur per day of catheterization?
5%
What is the MOA of nitrofurantoin?
damages bacterial DNA/proteins
What is the spectrum of nitrofurantoin?
e.coli
staphylococci
enterococcus faecalis
citrobacter
klebsiella
What are the adverse effects of nitrofurantoin?
GI upset
nausea
headache
darkens urine (not dangerous)
RARE: SJS/TEN
What can occur with long term use of nitrofurantoin?
neuropathy
pulmonary fibrosis
hepatic fibrosis
What are CIs of nitrofurantoin?
do not use in renal dysfunction
-CrCl < 30ml/min
do not use in late pregnancy
-risk of neonatal hemolysis at 36-42 weeks
patients with G6PD deficiency
What is a drug interaction of nitrofurantoin?
increase K with spironolactone
How should nitrofurantoin be taken?
with food
-increases absorption and decreases GI se
What is the MOA of fosfomycin?
inhibits cell wall formation, bactericidal
-different MOA from BLs
True or false: resistance is high to nitrofurantoin and fosfomycin
false
What is the spectrum of fosfomycin?
enterobacteriaciae including ESBLs
enterococcus
DOES NOT RELIABLY COVER PS. AERUGINOSA
What are the adverse effects of fosfomycin?
GI upset
diarrhea
headaches
hypokalemia
