Microbiology 6: Urinary Tract Infections Flashcards
What is the most common causative organism for UTI’s ?
E.coli
Name a virulence factor of some E.Coli serotypes that make them well adapted to cause UTIs ?
P-fimbriae
These allow the bacteria to adhere to the epithelium
Which commensal skin bacteria is a rare cause of UTI but is more common in patients with Prosthesis e.g they have a long term in dwelling catheter ?
Staphylococcus epidermidis
Which 4 organisms are more common causes of UTIs in people with structural abnormalities ?
Proteus mirabilis
Pseudomonas
Klebsiella aerogenes
Enterococcus faecalis
List 4 neurological causes of obstruction in the urinary tract ?
Poliomyelitis
Tabes dorsalis
Diabetic neuropathy
Spinal cord injury
Which organisms can cause a UTI which is negative for nitrites but positive for leucocytes on urine dipstick ?
(Non coliform bacteria)
Staphylococcus saphrophyticus
Enterococcus faecalis
Could also be urethral syndrome
List 3 ways you could collect a urine sample ?
Mid stream urine (MSU)
Catheterisation
Supra Pubic aspiration
What is the most common causes of Sterile pyuria? (raised WCC but no growth on culture)
Prior treatment with antibiotics
What colour is E.coli on chromogenic agar ?
Pink
What is thew most common treatment for an uncomplicated UTI ?
Empirical treatment - Trimethoprim (3 days)
Although the resistance of E.coli is rapidly increasing so check with local governance.
Which infections occur in patients that have indwelling catheters ?
Candida
What is the most common treatment for Pyelonephritis ?
Co-amoxiclav +- gentamicin
Which organism that is not E.Coli tends to cause UTIs particularly in young women?
Staphylococcus Saphrophyticus
Name a congenital abnormality that causes oligohydramnios and can cause Potter’s syndrome in male neonates?
Posterior urethral valve (PUV)
Give an example of a paediatric cause of Kidney scarring ?
Vesicoureteric reflux (VUR)
