UTIs Flashcards
What are the px groups that are more at risk of UTIs (5)?
1) <3 y/o (eg. underlying abnormality
2) Young healthy women (short urethra)
3) Elderly
4) Catheterised px (in-hospital, stroke)
5) Underlying abnormalities (eg. obstruction, calculi, neurogenic bladder)
What are 6 predisposing factors for UTIs?
1) Young child (obtuse vesicourethral angle → reflux)
2) Calculi (renal and ureteric)
3) Obstruction (eg. prostatism)
4) Congenital structural abnormalities
5) Catheter
6) Neurological conditions
7) Pathogenic factors (eg. attachment, type 1, P fimbriae)
What are upper urinary tract infections known as?
Pyelonephritis
What are lower urinary tract infections known as?
Cystitis
Are upper or lower urinary tract infections more common?
Lower
Does bacteraemia indicate upper or lower urinary tract infection?
Upper
What are 8 possible pathogens for UTIs?
1) E. coli
2) Staph saprophyticus
3) Klebsiella spp.
4) Proteus spp.
5) Citrobacter spp.
6) Enterococci
7) Pseudomonas aeruginosa
8) Candida spp.
What are 4 causative organisms for UTIs in catherised px/ px with structural abnormalities?
1) Proteus spp.
2) P. aeruginosa
3) Enterococci
4) Candida spp.
How are urine samples collects in px with catheters?
Through a sampling port (not urine bag)
What are 4 UTI lab investigations?
1) Urine dipstick (WBC, RBC, nitrates)
2) Urine microscopy (Pyuria)
3) Urine culture
4) Suprapubic aspirate
What are the 3 most important things to look out for in a Urine “dipstix” for px with UTI?
1) Leukocyte esterase → WBC (infection)
2) Nitrate reduction → E. coli or other common UTI organisms
3) Blood (hematuria)
What are the parameters for pyruria?
WBC > 100/uL
What are the parameters for haematuria?
RBC > 100/uL
If RBC>100/uL and WBC>100/uL in a urine microscopy, what would be the most accurate conclusion?
Haematuria, not pyuria
Overgrowth during storage and transport of urine samples for UTI testing >____mins can give a false positive.
90mins
Is a urine culture of >100 000 cfu/ml, single species significant?
Yes
Is a urine culture of 1000-100 000 cfu/ml, single species significant?
Maybe lmao
What are some key steps to prevent mixed culture due to contaminating organisms?
1) Clean perineum before collection
2) Collect cleanly (mid-stream)
3) Ensure quick transport to lab (<90min)
4) Boric acid in urine specimen container
5) Use dip-slide
6) Refrigerate @ 4 deg C if delay
What are 4 key things to take into account in diagnosing a px for UTI using urine culture?
1) Bacterial count
2) Mixed/single organism
3) Presence/absence of catheter
4) px age/clinical context/symptoms/signs
What are 5 empirical antibiotics used in UTI?
1) Co-amoxiclav
2) Cephalosporins
3) Cotrimoxazole
4) Aminoglycosides
5) Fluoroquinolones
What are 2 antibiotics ONLY used in lower UTIs?
1) Nitrofurantoin
2) Nalidixic acid
What antibiotics are most commonly used for uncomplicated UTIs?
Oral cephalosporins
What 2 antibiotics CANNOT be used for urinary infection?
1) Erythromycin
2) Clindamycin
(metabolised in liver, don’t make it to urinary tract)
How long is a typical course of antibiotics for an uncomplicated UTI?
3 days
How long is a typical course of antibiotics for an upper UTI?
at least 2 weeks (usually start with IV ABs until fever subsides)
What are some causative organisms of STDs that result in urogenital infections?
Ulcers:
1) Syphilis
2) Haemophilus ducreyi
3) HSV
Discharge:
1) Neisseria gonorrhoeae
2) Chlamydia trachomatis
3) Mycoplasma genitalium
Warts:
1) HPV
Systemic:
1) HIV
2) Hep B
Others:
1) Lymphogranuloma venerum
What are the tests for syphilis (3)?
Treponemal (recommended but stays +ve for life):
1) TPHA (Treponema pallidum haemagglutination)
2) EIA (Enzyme immunoassay)
Non-treponemal:
1) RPR (Rapid Plasma Reagin)
2) VDRL (Venereal Disease Research Laboratory)
Which syphilis tests are used for screening?
Treponemal: EIA and TPHA
(stay positive for life)
Which syphilis tests are used to monitor disease activity?
Non-treponemal: RPR and VDRL
(prone to false +ve/-ve)
Which syphilis tests cross-react with non-syphilis treponemal infections (eg. yaws)?
Treponemal: TPHA and EIA
What are the clinical presentations of Neisseria gonorrhoeae infections?
1) Copious urethral discharge in men
2) Asymptomatic/mild in women
3) Anal discharge in proctitis (HIV/male)
4) Acute calpingitis
5) Pharyngitis
6) Disseminated gonococcal infection
What are the lab tests for N. gonorrhoeae infections?
1) NG culture in special media (Use Amies transport media ± charcoal)
2) NG PCR
What are the antibiotics used for N. gonorrhoeae infections?
1) Ceftriaxone (though there is growing 3rd gen cephalosporin R)
2) Azithromycin
3) Ciprofloxacin (R in most communities)
What are the antibiotics used for concurrent N. gonorrhoeae and C. trachomatis infections?
Ceftriaxone + Doxycycline /+ Azithromycin
What are the clinical presentations of Chlamydia trachomatis infections?
Usually silent or cause simmering disease over the years but sequelae:
1) PID → infertility
2) Acute salpingitis
3) Ectopic pregnancy
What is the criteria for C. trachomatis screening?
Sexually active women < 25 y/o
What are the lab tests for a possible C. trachomatis infection?
CT PCR
(collect from endocervical, vaginal, urine)
What are antibiotics are used for Neisseria gonorrhoeae UTI?
1) Doxycycline
2) Azithromycin
What are antibiotics are used for Mycoplasma genitalium infections?
1) Doxycycline
2) Azithromycin
What are the lab tests for a possible Mycoplasma genitalium infection?
NAAT (eg. PCR)
What are some non-gonorrhoeae and non-chlamydia UTI/discharge-causing infections?
1) Candida
2) BV (eg. Gardenerella, mobiluncus. etc.)
3) Trichomonas vaginalis
What are the lab tests for a possible Bacterial Vaginosis?
1) Gram stain
2) PCR for causative organisms
What are the lab tests for a possible Trichomonas vaginalis infection?
1) Wet mount
2) PCR
What are the 2 most common causes of uncomplicated UTI/cystitis?
1) E. coli
2) S. saprophyticus
What are the empirical treatments for complicated UTI/cystitis in a non-pregnant px?
Nitrofurantoin/Cotrimoxazole
- escalate with Ciprofloxacin/ Coamoxiclav/ 1-3rd gen cephs/ Fosfomycin
What are the empirical treatments for complicated UTI/cystitis in a pregnant px?
Coamoxiclav/1-3rd Gen Cephs
(eg. ceftazidime, cefuroxime, cephalexin)
- escalate with: Fosfomycin/ Nitrofurantoin (if not @ term)
What are the 6 most common causes of complicated UTI/pyelonephritis?
1) ESBLs
2) E. coli
3) Klebsiella spp.
4) Pseudomonas aeruginosa
5) Proteus spp.
6) Enterococcus
What are the empirical treatments for complicated UTI/pyelonephritis in a non-pregnant px?
Ciprofloxacin/Cotrimoxazole
- escalate with: Carbapenems/Aminoglycosides
What are the empirical treatments for complicated UTI/pyelonephritis in a pregnant px?
Pip-tazo/Meropenem
