UTI's Flashcards
Pyelonephritis
Inflammation of the kidneys due to infection.
Cystitis
Inflammation of the bladder due to infection.
Upper UTI’s affect where?
Kidneys and ureter
Lower UTI’s affect where?
Bladder and urethra
Uncomplicated UTI
Uncomplicated UTI occurs in patients who have a normal, unobstructed genitourinary tract, who have no history of recent instrumentation, and whose symptoms are confined to the lower urinary tract. Uncomplicated UTIs are most common in young, sexually active women.
How do uncomplicated UTI’s respond to treatment?
Infections with get better without treatment failure using first line antibiotics.
Complicated UTI
A complicated UTI is an infection with an underlying condition, such as structural or functional abnormalities of the genitourinary tract which increases the risks of acquiring an infection or of failing therapy.
How are lower UTI’s usually caused?
Usually caused by an ascending infection where bacteria in the rectal area moves up the urethra and into the bladder causing cystitis.
What are the three main bacteria that commonly cause UTI’s?
E.coli, Klebsiella, Proteus species.
E.coli, Klebsiella, Proteus species are gram what?
Gram negative
What is the most common gram positive bacteria that causes UTI’s?
Staphylococcus saprophyticus
Who does Staphylococcus saprophyticus most commonly affect?
Young sexually active women
What are the main risk factors of UTI’s ?
Sexual intercourse Being female Post-menopausal women Foley catheter Diabetes Mellitus Impaired bladder emptying (increased dwelling times)
How does sexual intercourse cause UTI’s and why does this affect women more?
Bacteria enters the urethra. This affects women more because they have shorter urethra’s.
Why are post-menopausal women more at risk of UTI’s?
There is a decrease in oestrogen which causes the protective vaginal flora to be lost.
How does diabetes mellitus increase risk of having a UTI?
Hyperglycaemia inhibits the action of neutrophils so they cannot phagocytose the bacteria causing the UTI.
What are the symptoms of cystitis?
Suprapubic pain
Dysuria
Frequent urination and urgency
What are the symptoms of a UTI in infants?
Fever, fussy, feed poorly.
What are the symptoms of a UTI in elderly patients?
Fatigue, incontinence and delirium
What symptoms are suggestive of an upper UTI infection and not a lower?
Systemic signs - fever, nausea and vomitting.
Pain are the costovertebral angle.
Leukocytosis (high levels of wbc’s in blood)
What may be seen in the urinalysis of a lower UTI?
Pyuria (makes the urine appear cloudy).
Pyuria
White blood cells in the urine
What quantifies an abnormally high WBC in urine?
> 10wbc/ml
What may a dipstick show in cases of lower UTI?
Postive test for leukocyte esterase and nitrites.
Leukocyte esterase
Enzyme produced by white blood cells.
Why are nitrites present in lower UTI’s?
The gram negative bacteria produce nitrites.
What is the gold standard to testing for UTI’s?
Urine culture of bacteria
If the urine tests positive for Pyuria and negative for urine culture what is the condition?
Sterile pyuria
What is isolated urethritis most commonly caused by?
Neisseria gonorrhoea Chlamydia trachomitis (both STI's)
How is acute pylonephritis most commonly caused?
Ascending infection up the urethra and bladder to the kidneys.
Vesicoureteral reflux
Vesicoureteral reflux (VUR) is when the flow of urine goes the wrong way. This condition is more common among infants and young children.
How does Vesicoureteral reflux occur?
Failure of the vesicoureteral orifice.
Ascending infection is commonly caused by what?
E.coli, Klebsiella, Enterobacter and Proteus species.
E.coli Enterobacter and Proteus species are common where?
Bowel flora
Hematogenous infection causing acute pyelonephritis is caused how?
Septicemia
Bacteremia
Infective endocarditis
What are the most common species causing acute pyelonephritis by hematogenous infection?
Staphylococcus aureus
E.coli
Recurrent UTI’s usually occur why?
Anatomical problem
What can recurrent UTI’s cause?
Chronic pyelonephritis
Papillary necrosis
Acute pyelonephritis
Bacterial infection of the upper urinary tract (usually develops from a lower UTI).
Asymptomatic bacteriuria
Presence of bacteria in urine without any urinary symptoms.
When is asymptomatic bacteriuria treated?
Only treated in pregnancy or before a urological procedure.
What can cause sterile pyuria?
Prior antibiotics Stones Tumour TB/Chlamydia Interstitial nephritis
What makes urine bactericidal?
Urine pH, osmolarity and urea.
What is the concern if Staph.aureus is found in the urine?
Concern that there is an infection in the blood.
What is the concern if you see fungi such as candida in the urine and it is not caused by thrush?
Concern that there is an infection in the blood.
Nephrolithiasis
The process of forming a kidney stone.
The presence of nitrites in urine tells you what type of bacteria are present?
Gram negative as they produce nitrites.
Blood on a urine dipstick test indicates what?
Potential tissue damage / Potential stones
What are the symptoms of a UTI used to make clinical decisions?
Dysuria Frequency Urgency Suprapubic tenderness Polyuria Haematuria
What is the criteria for diagnosing a UTI?
3 or more of the symptoms with the absence of vaginal discharge/irritation.
If the urine is not cloudy what is the thought process?
Indicates not a UTI infection - so look for other diagnoses.
Why are UTI’s a risk for pregnant women?
Increase risk of fetal loss.
Which antibiotic is commonly prescribed for uncomplicated lower UTI’s?
Nitrofurantoin
What type of antibiotics are used to treat UTI’s?
Beta-lactams
How do Beta-lactams work?
Inhibit bacterial cell wall synthesis.
Why is Ciprofloxacin not used to treat UTI’s?
Too valuable to be used as a first line antibiotic treatment.
Why is UTI less common in men?
Longer urethra and the antibacterial properties of prostatic fluid.
Are men more likely to get complicated or uncomplicated UTI’s?
Complicated
UTI in men is commonly associated with what abnormalities?
Urological abnormalities such as enlarged prostate / bladder outlet obstruction / instrumentation.
What are the risk factors of a catheter associated UTI?
Duration of catheterisation
Diabetes
Old age
Lapses in catheter care
What are the symptoms of a catheter associated UTI?
Systemic signs - fever, nausea and vomitting.
Pain are the costovertebral angle.
What is classed as a recurrent UTI?
2 or more UTI’s in 6 months / 3 or more UTI’s in a year.
What is the commonest pathogen due to ascending infection?
E.coli
How do bacteria adhere to the urinary tract?
The adhere using pilli and fimbraie which allow them to attach to the epithelium.
What are the symptoms of acute pyelonephritis?
Same as that of upper UTI's: Systemic signs - fever, nausea and vomitting. Pain are the costovertebral angle. Leukocytosis Dysuria Frequency Urgency Suprapubic tenderness Polyuria Haematuria
Leukocytosis
High levels of WBC’s indicating infection.
What antibiotics are used to treat uncomplicated cystitis?
Nitrofurantoin
Trimethoprim
What antibiotics are used to treat uncomplicated acute pyelonephritis?
Ciprofloxacin
Ceftriaxone
How would you detect if an ascending UTI is beginning to cause pyelonephritis?
The UTI would also start presenting with systemic features such as fever and back pain.
Sterile pyuria is commonly caused by what?
STI’s such as chlamydia trachomatis and neisseria gonorrhoeae.
