UTI - Self LEarn Flashcards
Define Pyuria
Pus cells present in the urine
Sterile pyuria = pus cells but -ve on urine cultures
What can cause chronic pyelonephritis?
Recurrent UTIs but also:
- DM
- Vesico-uretic reflux
- Urinary Obstruction
Whats the difference between a complicated and uncomplicated UTI?
Uncomplicated = Young sexually active women with a clear correlation to sexual activity
Complicated = Any other so kids, men, abnormal tracts, immunosuppression, tumours, chronic retention or BOO
When do you we treat women with UTIs?
IF they have 3 or more symptoms from:
Dysuria/frequency/urgency/suprapubic pain/polyuria/haematuria
Then you start on empirical Abx
If all 3 dipstick components (nitrites/protein/leucocytes) are +ve -> Empirical Ab
If they only have 2 symptoms do an MSSU
What mostly causes UTIs in men?
Recurrent UTIs tend to be a sign of prostatitis in older men or STIs in younger men (chlamydia/gonorrhoea)
Whats the risk of UTI in pregnancy?
Pyelonephritis & Premature delivery
How do you approach pregnant women re UTIs?
Screen with an MSSU culture at first antenatal appointment.
Treat even if asymptomatic
How does pyelonephritis present vs lower UTI?
Lower UTIs:
- Suprapubic Pain
- Dysuria
- Frequency
- Urgency
- Polyuria
- Haematuria
Pyelonephritis:
- Loin Pain
- Fever
- ~systemic unwellness
- Severe cases have bacteraemia (rigors, N&V etc)
How do you manage pyelonephritis?
Urine culture
Empircal Abx
Blood cultures if systemically unwell
How would a UTI appear in children? and how would you investigate?
Often very unspecific. Any young child whos sick or has unexplained fever might be a UTI.
So any child like that gets an MSSU and follow up to ensure they don’t have vesico-ureteric reflux
What are the main community and hospital acquired UTI bacteria?
Mostly E.Coli Also: - Klebsiella sp. - Proteus sp. - Pseudomonas sp.
What extra investigation would you do for a patient with a proteus or Klebsiella UTI?
Non-contrast CT for stones.
They’re produce a lot of stones
What are the important parts of the dipstick test for a UTI?
Nitrites (produced by bacteria)
Protein (inflammation or renal pathology)
Leucocytes
If all 3 are present its an indication for empirical Abx
Also blood
What are the indications for a MSSU?
1) Women in which the dipstick is inconclusive
2) Men
3) Acute pyelonephritis
4) Pregnant (screening & Symptomatic)
5) Failed Abx or persistant symptoms
6) Recurrent UTIs
7) Children
How do you take a MSSU?
1) Discard the first 10-20ml of stream
2) Early morning urines are more likely to be +ve
3) Boric Acid container prevents overgrowth
If its a catheter specimen take it from the sampling port not the bag
How do you take a urine sample from a child?
Most kids can't give a decent MSSU. So a clean catch urine sample is preferable. IF that fails: - Urine collection Pad - Catheter Sample - Suprapubic Aspiration
How do we detect pyuria?
With microscopy
Significant pyuria = >10WBC/mm^3
How do we tell if its contamination or infection on a urine culture?
10^4 organisms/ml indicates infection > contamination
(10^5 in asymptomatic bacteriuria)
MIxed organisms usually means contamination
What factors predispose to a UTI?
- Female
- Coitus or childbirth
- Pregnancy
- Anatomical abnormalities
- Renal Cysts
- Pre-existing parenchymal damage (e.g. recurrent pyelonephritis)
- Stones
- Immunosuppression
- Urinary Tract instruments e.g. cystoscopy
- Foreign Body e.g. catheter or stent
Why does pregnancy predispose you to UTIs?
Your urine is static due to physical pressure from the foetus and because progesterone dilates ureters
Its almost inevitable that patients with indwelling catheters get bacteriuria, how do you approach Catheter-related infections?
Dont do culture or treatment if they’re not symptomatic.
If they are do a urine culture and empirical Abx, the catheter should be changed immediately prior to treatment.
Asymptomatic Bacteriuria is quite common in adult women and men with BPH, in which cases would we culture and treat and when would we leave it be?
We’d only do a urine culture and treat such patients if they’re:
- Pregnant
- Undergoing urological surgery
- Undergoing surgery involving prosthesis
What can cause sterile pyuria?
- Abx in blood preventing bacterial growth
- Renal Tuberculosis
- Genito-urinary infections
- If its recurrent its might be stones, malignancy, chronic prostatitis or interstitial cystitis.
How do we rule out renal TB in sterile pyuria?
Collect 3 early morning MSSUs for ZN stains & TB cultures.
