Flashcards in UTI Deck (21):
What is the most common infecting organism in acute infection?
E. coli, 95% of UTI are caused by single bacterial species
O1,O2,O4,O6,O7, O8,O75,O150, O18ab
What other for organisms are responsible for UTI?
Proteus mirabilis -renal stones
Staph sapro- virulence factors, common in young women
What are the antibacterial host defences?
Urine - osmality, ph, organic acids
Urine flow and micturtion
Urinary tract mucosa- bacteriacidal activity, cytokines
Where do the organisms for UTI come from?
Contamination from perianal and vulvar area- vaginal introitus, periturethal area
Where do the bacteria go once in the bladder?
Ureter, then to renal pelvis and parenchyma, especially with reflux
How does obstruction affect susceptibility to UTI?
Extra renal- valves, stenosis, bands, calculi, extrinsic urethral compression, bph
Intra renal- nephrocalconis, uric acid nephropathy, analgesic nephropathy, PKD, hypokalaemic nephropathy,
How can neurological problems affect obstruction?
Poliomyelitis, tabes dorsalis, diabetic nephropathy, spinal cord injuries
What is the haematogenous route?
Haematologist- kidney frequently site of abcesses in patients with s aureus bacteraeima or endocarditis
Rarely gram neg
What are upper UTI symptoms?
Fever, rigors (gram neg)
Luts before upper occasionally
How can UTI present in older patients?
Asymptomatic, not diagnostic, atypical, eg abdo pain and change in mental status
What the ix for UTI?
Dipstick, msu for microscopy, culture, sensitivities
Bloods for upper
What does a complicated UTI refer to?
Infection with functional or structural abnormalities including indwelling catheter and calculi
Men, pregnant women, children, patients. Treat asymptomatic pregnant women.
How do you interpret culture?
White blood cells- more than 10^4, inflammation. Absent in childhood
Sterile pyuria- chlamydia, vaginal infection, renal pathology
What are the methods of sampling?
Msu, Catheterisation, supra public aspiration
What is sterile pyuria due to?
What is the cut off for bacteria in culture for infection?
Greater than 30 colonies. 10 to the 5 colony forming units.
Sterile less than 10 to 4
How is nitrofurantoin effective?
Urinary antiseptic, broad spectrum
Doesn't have systemic absorption, so take after you've gone to the loo so fresh urine has abx
What is recommend in urosepsis?
What causes fungal infection?
Candida, indwelling catheter, abx can affect normal flora. Treat for thrush
What part of the kidney is more likely to be infected?
Few needed to infect the medulla, 10000 times more needed for cortex
Sepsis, septicaemia, aggressive tx, broad spectrum
Give co amox and or gentamicin