Urinary Tract Infection COPY Flashcards
Which sex are UTI’s most common in?
Females
What is the definition 0of bacteriuria?
Bacteria in the urine - may be symptomatic/asymptomatic
What is a UTI?
A diagnosis based on symptoms and signs. Tests which prove bacteria in the urine may provide additional information
What parts of the urinary tract fall under the classification of lower urinary tract infection?
- Bladder (cystitis)
- Prostate (prostatitis)
- Urethra (Urethritis)
What parts of the urinary tract are involved in upper UTI?
Kidney/renal pelvis (pyelonephritis)
What is the definition of an uncomplicated UTI?
Normal renal tract structure and function
What is the definition of a complicated UTI?
Structural/functional abnormality of the GU tract e.g. obstruction, catheter, stones, neurogenic bladder, renal transplant
What are groups of risk factors for the development of a UTI?
- Increased bacterial inoculation
- Increased binding of uropathogenic bacteria
- Decreased urine flow
- Increased bacterial growth
What are causes of increased bacterial inoculation?
- Sexual activity
- Urinary incontinence
- Faecal incontinence
- Constipation
What are causes of decreased urinary flow which can lead to the development of UTI?
- Dehydration
- Obstructed urinary tract
What conditions can increase bacterial growth in the urinary tract?
- DM
- Immunosuppression
- Obstruction
- Stones
- Catheter
- Renal tract malformation
- Pregnancy
What are symptoms of cystitis?
Complex of:
- Frequency
- Dysuria
- Urgency
- Suprapubic pain
Plus:
- Polyuria
- Haematuria
What are symptoms of acute pyelonephritis?
- Fever
- Rigors
- Vomiting
- Loin pain/tenderness
- Costovertebral pain
- Associated cystitic symptoms
- Septic shock
What are the most commonly implicated organisms which cause UTIs?
- E.Coli
- Proteus spp
- Klebsiella aerogenes
- Enterococcus faecalis
- Staph epidermidis
What organism is most commonly implicated in UTI?
E. Coli
What are symptoms of prostatis?
- Pain - perineum, rectum, scrotum, penis, bladder, lower back
- Fever
- Malaise
- Nausea
- Urinary symptoms
- Swollen tender prostate on examination
What are signs of a UTI?
- Fever
- Abdo/loin pain
- Distended bladder
- Enlarged prostate
If you suspected someone had a UTI, what investigtions might you do?
- Urine dipstick
- MSU culture/microscopy
- Bloods - FBC, U+E’s, CRP, Blood culture
Consider
- Fasting glucose
- Imaging - consider US, urodynamics, cystoscopy, CT urogram/Abdo/pelvis
When would you consider treating a UTI without investigation?
Non-Pregnant women with >/= 3 symptoms of cystitis, and no vaginal discharge
What does a negative diptick reduce the probability of a UTI to?
<20%
What organisms reduce nitrates to nitrites?
Gram-negative organisms
What organism can be responsible for a sterile pyuria?
TB
What are infectious causes of a sterile pyuria?
- TB
- Recently treated UTI
- Inadequately treated UTI
- Appendicitis
- Prostatitis
- Chlamydia
What are non-infectious causes of sterile pyuria?
- Calculi
- Renal tract tumour
- Papillary necrosis
- Tubulointerstitial nephritis
- Chemical cystitis
- PKD
- Recent catheter
- PRegnancy
- SLE
- Drugs - e.g. steroids
What properties of urine reduce bacterial survival?
- Osmolality > 800 mOsm/Kg
- Low/high pH
How does urine flow reduce risk of UTI?
Flow washes out bacteria
What might indicate infection on urine diptick?
- Positive Leucocytes
- Positive nitrites
- Mixture of the two - most sensitive
What is diagnostic of a UTI on urine culture in men?
Culture demonstrates ≥10^2 CFU/mL of a single or predominant organism in a patient plus symptoms specific to the urinary tract
What is diagnostic of asympotmatic bacteruria in a man?
Urine culture demonstrates ≥10^5 CFU/mL of a single organism obtained by clean catch on one occasion from a man without specific urinary tract symptoms
What might you consider as a differential diagnosis for a UTI in a man?
- BPH
- Prostatis
- Prostate cancer
- Pyelonephritis
- Urinary calculi
- Gonococcal/chalmydia urethritis
- Bladder cancer
- Renal cancer
- Epididymitis
- Reactive arthritis
What is the primary cause of UTIs ini women?
Sexual intercourse
Why might you consider doing a CT abdo/pelvis?
Used to rule out renal or peri-renal abscess if symptoms do not respond to antimicrobial therapy after >7 days’ duration.
Why might you do cystoscopy in someone with recurrent UTI?
Rule out lower tract abnormalities. Indicated only in patients in whom conventional treatment has failed or who have unusually severe or persistent symptoms. May find:
- Tumour
- Bladder stone
- Foreign body
- Diverticulum
When would you consider performing a renal ultrasound in someone with a UTI?
Only in patients in whom conventional treatment has failed or who have unusually severe or peristent symptoms. Looking for:
- Kidney stones
- Hydronephrosis
- Renal abscess
- Renal scarring
If on urine culture there were <10^5 CFU/mL, but pyuria was present (>20 WBC/mm^3), would this be considered a UTI?
Yes
If the dipstick result is negative but the symptoms suggest a UTI, what are the chances of a UTI being present?
Still relatively high
When would you consider doing imaging in someone with symptoms of a UTI?
- Men with upper UTI
- Failure to respond to treatment
- Recurrent UTI
- Pyelonephritis
- Unusual organism
- Persitent haematuria
How would you manage a lower UTI in a non-pregnant woman?
If >/=3 symptoms of cystitis, no vaginal discharge:
- Trimethoprim - 3 days, or
- Nitrofurantoin - 3 days
When would you avoid giving nitrofurantoin?
If eGFR <30
How would you approach managing a UTI if first line treatment failed in a non-pregnant women?
Culture urine and treat according to resistance
How would you manage a pyelonephritis?
- Gentamicin + Amoxicillin - 7 days (or 10-14 if complicated)
- If allergic - ciprofloxacin
How would you treat an uncomplicated lower UTI in a men?
- Trimethoprim - 3 days
OR
- Nitrofuratoin (eGFR>30) - 3 days
How would you manage a complicated UTI?
Treat for 7-14 days
- Co-amoxiclav - 8 hrly
OR
- Co-trimoxazole - 8 hrly
If allergic - ciprofloxacin
How would you manage a UTI in pregnancy?
Get expert advice. Consider the following advice:
- Don’t use trimethoprim 1st trimester - don’t use at all really
- Don’t use nitrofurantoin in 3rd trimester
- Avoid ciprofloxacin
- Consider cefalexin
What can UTIs during pregnancy cause?
- Preterm delivery
- Intrauterine growth restriction
If a man is showing signs of prostatitis, how would you manage it?
Consider ciprofloxacin for long course (4 weeks) - penetrate prostate fluid better
If a catheterised patient developed a UTI, how would you manage it?
- Change catheter
- Culture urine
- Antibiotics not indicated unless systemic infection -> if likely, treat as for complicated UTI or pyelonephritis
What neurological symptom may indicate a UTI in an elderly individual?
Confusion
What are features of urinary tract TB?
- Sterile pyuria
- Dysuria
- Frequency
- Suprapubic pain
- Malaise
- Fever
- Night sweats
- Weight loss
- Back/flank pain
- Visible haematuria
What is reflux nephropathy?
Nephropathy caused by vesicoureteric reflux due to dysfunctional vesicoureteric valve, and infection acquired in infancy or early childhood. Typically, there is papillary damage, tubulointerstitial nephritis and cortical scarring - leading to clubbed calyces
Why is nitrofurantoin not recommended in pregnancy in 3rd trimester?
Can cause haemolytic anaemia in the baby
What is the definition of a recurrent UTI?
3 or more episodes in a 12-month period
