UTI Flashcards
What is a UTI?
Bacteria in the urinary tract that causes clinical infection.
What is cystitis?
LUTI/infection of bladder
What is another term for a LUTI?
Cystitis
What is pyelonephritis?
UUTI/Kidney infection
What is another term for a UUTI?
Pyelonephritis
Which parts of the urinary tract are normally sterile?
Kidneys, ureters and bladder
What kind of bacteria normally colonize the lower urethra?
Coliforms and enterococci
What makes a UTI complicated?
Systemic upset or urinary tract structural abnormalities.
What is bacteriuria?
Bacteria in the urine
Does bacteriuria always mean a UTI?
No, elderly or catheterised patients may have it too.
Is cystitis just caused by infection?
No, just means inflammation of bladder so can be many causes.
What three factors regulate the presence of infection?
Host- Immunological status, behaviour etc
Organism- Type of organism, virulence etc
Environment- Medical devices, anatomy/urinary retention
What are some risk factors for contracting a UTI?
Women
Catheter
Structural abnormalities
What are the two routes bacteria can take to infect the urinary tract?
Ascending
Blood
How common is blood stream infection of the kidneys?
Quite uncommon
What is an important factor of bloodstream infections of the kidney?
Multiple small abscesses
Name five important bacteria that can cause UTI
E. Coli Klebsiella Enterobacter Proteus Pseudomonas
What is the most common form of bacteria to infect the urinary tract?
Lactose fermenting coliforms such as E. Coli, Klebsiella and Enterobacter
What makes E. Coli exceptionally good at causing UTI?
Long flagellum that allow it to adhese and climb up.
What part of E. Coli is responsible for a lot of its effects such as fever?
Endotoxin
Where is endotoxin found in E. Coli?
LPS layer
What does proteus do in urine?
Breaks down urea to ammonia to increase pH and precipitate out struvite stones.
What does proteus infection smell like?
Burnt chocolate
What is pseudomonas infection associated with?
Catheters and medical devices
What is the best antibiotic for a pseudomonas infection?
Ciprofloxacin
How should ciprofloxacin be administered?
Oral or IV
Which groups should not receive ciprofloxacin?
Children and pregnant women
What are the three major gram negative causes of UTI?
E. Coli
Proteus
Pseudomonas
What are the two main gram positive causes of UTI?
Enterococci
Staph
Which enterococci is important to know?
Enterococci faecalis
Where is enterococci usually acquired?
Hospital
Which two forms of staph commonly cause UTI?
S. Aureus
S. Saprophyticus
What kind of UTI does S. Aureus normally cause?
Blood born
Where is S. Saprophyticus normally found?
Female reproductive tract
What group is most affected by S. Saprophyticus?
Women of childbearing age
How do you diagnose a UTI?
Dysuria
Increased urination frequency
Nocturia (change from baseline)
Haematuria
What three factors suggest UUT involvement?
Fever
Rigors
Loin pain
What are some risk factors for a LUTI?
Female
Sexually active
Diabetes
Obesity
What three organisms tend to cause LUTI?
Klebsiella
Enterobacter
S. Saprophyticus
What are some risk factors for UUTI?
HIV/Immunosuppression
Diabetes
Congenital abnormalaties
What four organisms tend to cause UUTI?
Klebsiella
Enterobacter
S. Aureus
Proteus
How should you collect a urine sample?
Midstream
Why should you collect a midstream urine sample?
Because the first part tends to contain bacteria from the urethra
What should you do before collecting a midstream urine sample?
Clean perineal/urethral meatus with sterile saline (not antiseptic!)
What type of container should you ideally collect a urine sample in?
Sterile universal (white top)
How soon should a sample in a sterile universal be tested?
<2h
If it’s going to take longer than 2h to test a urine sample what type of container should you use?
Boricon (red top)
How long is a Boricon container good for?
Up to 24h
If a midstream sample isn’t possible what other collection techniques are there?
Clean catch
Bag urine
Catheter specimen
Suprapubic aspiration
What groups is a clean catch urine sample good for?
Children
Cog or physically impaired
How does a clean catch sample work?
Clean, urinate but into toilet, stop, urinate into container until half full.
Which group is a bad urine sample good for?
Babies
What is a major problem with a bag urine sample?
Often contaminated with bowel flora
What is a good result from a bag urine sample?
Negative (positive could be contaminated)
Can a dipstick test be used to diagnose a UTI?
No but can indicate one in select patient groups
Which groups should not have their urine dipstick tested?
Elderly or catheterised
What two things on a urine dipstick indicate infection?
Leukocytes
Nitrites
Infection with which organism does not give positive nitrites test?
Pseudomonas
How is a UTI diagnosed in the lab?
Microscopy- rare and only in urgent cases
Urine culture
What are the three categories in the Kass criteria?
Probable UTI- >10^5 organisms/ml
Probably contamination- 10^4 organisms/ml
No significant bacteriuria- <10^3
What group is the Kass criteria applied to?
Women of childbearing age
What are pure and mixed growths?
Pure- one organism
Mixed- 2+
When is a >10^5 organisms/ml significant?
When it’s caused by one organism (if 2+ then probably not significant)
How should you treat an uncomplicated LUTI?
Antibiotics
How long should antibiotics be given for in a LUTI?
3 days
What is Abacterial cystitis/Urethral syndrome?
Symptoms of UTI and pus cells in urine but no growth.
What can cause Abacterial cystitis/Urethral syndrome?
Early phase of UTI
Urethral trauma (honeymoon cystitis)
Chlamydia/gonorrhoea
How can you treat Abacterial cystitis/Urethral syndrome?
Alkalise urine for symptomatic relief
What is Asymptomatic bacteriuria?
Significant bacteriuria (>10^5 orgs/mL) but no pus cells and patient is asymptomatic.
How do you treat Asymptomatic bacteriuria?
You don’t unless pregnant
When should a catheterised patient be treated for a UTI?
> 10^5 orgs/mL and symptomatic
What is the empirical treatment for a LURI in a female?
Nitrofurantoin or trimethoprim orally (3 days)
What is the empirical treatment for uncatheterised male UTI?
Nitrofurantoin or trimethoprim orally (7 days)
What is the empirical treatment for complicated UTI or pyelonephritis seen by a GP?
Co-amoxiclav or co-trimoxazole (14 days)
What is the empirical treatment for complicated UTI or pyelonephritis seen in hospital?
Amoxicillin and gentamicin IV for 3 days
What is the local treatment for coliforms?
IV Gent for UUTI
Oral trimethoprim for LUTI
What is the local treatment for enterococci?
IV Amoxicillin
Which group should gent not be given to?
Pregnant women
What are some dangers of gent?
Renal damage
CNVIII damage
How long should gnet be prescribed for?
3 days