UTIs Flashcards
What are the peaks of UTIs for women?
Young child
Age of sexual activity
Child bearing
Elderly
When do men have peaks of UTIs?
Infancy
Elderly
UTIs are most commonly caused by what in the elderly?
Urinary tract obstruction
Eg. Enlarged uterus or prostate
What patient factors increase the risk of UTIs?
Shorter urethra
Obstruction - BPH, pregnancy, stones, tumours
Lack of flushing
Neurological problems - residual urine, likely to fester
Ureteric reflux - ascending infection from bladder
What bacterial factors increase likelihood of causing UTI?
Fimbriae
K antigen - polysaccharide capsule to resist host defences
Urease
Haemolysins
What are the most likely pathogens to cause UTIs?
Coliforms eg. E-coli
Apart from E-coli, what pathogens can cause UTIs?
Proteus Enterococcus Coagulase negative staph Pseudomonas Staph aureus
What is the most common UTI?
Cystitis
Describe the presentation of cystitis
Urgency and frequency of urination
Pain (burning)
Sometimes a low grade fever
Asymptomatic bacteriuria is generally not a problem unless in …
Pregnant women
Describe the presentation of pyelonephritis
Fever
Loin pain
Dysuria
Frequency of urination
Describe an uncomplicated UTI
Infection by a usual organism in a patient with a normal urinary tract and normal urinary function
Describe a the most common uncomplicated UTI
Females
Child bearing age
Common cystitis presentation
Describe a complicated UTI
When one or more factors are present that predispose the person to persistent infection, recurrent infection or treatment failure
What factors make the UTI complicated?
Abnormal urinary tract Virulent organisms Impaired host defences Impaired renal function (Most cases in children, men and pregnant women)
What investigations do we do for uncomplicated UTI?
Urine dipstick
What investigations do we do for complicated UTIs?
Culture urine
Turbidity
Dipstick testing
What are the ways of collecting urine for culture?
Mid stream urine
Collection bag
Catheter sample
Suprapubic aspiration
How isn’t nitrite a reliable test?
Not all bacteria produce the enzyme to make nitrite
What are urine dipsticks useful for in UTIs?
Good at telling us how likely they are NOT to have an infection
What are urine dipsticks not useful for?
Uncomplicated UTIs in women
Men with typical/severe symptoms
Catheterised patients (usually positive)
Older patients without features of infection
What is the role of culture in UTIs?
Guidance for treatment
Collect data - epidemiology
See if urine collection is good quality
Test sensitivity to Abx
What do we call the area of clearance when testing Abx sensitivity?
Zone of inhibition
How do we treat most cases of cystitis?
Self-limiting
No Abx necessary for most
When would we image the tract in UTIs?
All children
Septic patients
What is sterile pyuria?
Presence of increased WBCs in urine without a positive culture
What are some causes of sterile pyuria?
Already on Abx Urethritis Vaginal infection/inflammation Chemical inflammation TB Appendicitis
Describe the treatment for UTI
Increase fluid intake
Address underlying disorder
3 day course Abx - uncomplicated
5-7 day course - complicated
Describe Abx for simple cystitis
Trimethoprim or nitrofurantoin
3 day course
Describe Abx for complicated UTI
Trimethoprim, nitrofurantoin or cephalexin
5 - 7 days
Why is amoxicillin not an appropriate treatment for UTIs?
Many organisms causing UTIs are resistant to amoxicillin
Who do we do follow up UTI cultures for?
Children
Pregnant women
How do we treat pyelonephritis?
14 day course Agent with systemic activity Possibly IV Co-amoxiclav Ciprofloxacin Gentamicin
How and why do we give prophylaxis for UTIs?
3 or more episodes per year
No treatable underlying condition
Trimethoprim or nitrofurantoin
Single nightly dose
