UTI's Flashcards
Who get’s more UTI’s, women or men?
Women
What % of women have recurrent UTI’s at some point in their life?
20-30%
After what age do men experience UTI’s?
> 50
What is the route that bacteria normally take to cause a UTI?
from the urethra –> bladder
What is the main mechanism to cause nosocomial UTI’s?
catheters
What is the #1 cause of community and hospital acquired UTI’s?
E. coli
What % of community UTI’s are from E. coli?
80%
What % of community UTI’s are from coagulase-ned staph?
10%
What % of community UTI’s are from Proteus mirabilis?
5%
What % of nosocomial UTI’s are from E. coli?
40%
What % of nosocomial UTI’s are from other gram negatives?
25%
What % of nosocomial UTI’s are from other gram positives?
16%
What % of nosocomial UTI’s are from Proteus?
11%
What % of nosocomial UTI’s are from Cadida?
5%
What is the virulence factor for Proteus to cause urinary stones?
urease
Why are Cirobacter, Klebsiella, Enterobacter, Proteus, and Pseudomonas aeruginosa more frequently found in hospital-acquired UTI’s?
Because their resistance to antibiotics
Case: a young sexually active woman presents with a UTI. Which bug is common in these people?
Staphylococcus saprophyticus
So the other forms of coagulase-neg staph (epidermidis and enterococcus) are common in which patients?
Hospitalized pts
How do the human polyomaviruses (JC virus and BK virus) enter the body?
Respiratory tract
After entering the respiratory tract, where do the human polyomaviruses reside and become latent?
Kidneys
In which “situation” can human polyomaviruses reactivate asympatomatically and present as large amounts of viruses in the urine?
Pregnancy
Reactivation of human polyomaviruses in immunocompromised hosts may lead to what condition?
Hemorrhagic cystitis
In addition to human polyomaviruses, which other virus can cause hemorrhagic cystitis?
Adenovirus
Which parasite infectiosn result in cystitis and hematuria?
Schistosoma haematobium
What is the vector for Schistosoma haematobium?
Aquatic snails
How do the infected snail larvae enter the host?
By penetrating the skin
Where does Schistosoma haematobium mature in the body?
Liver
After maturing in the liver and entering the blood, how does Schistosoma haematobium enter the bladder to cause cystitis?
by penetrating the beins of the bladder wall
Schistosoma haematobium causes granulomatous reactions in the bladder, which leads to what change in the eggs?
calcification
Calcification of a Schistosoma haematobium egg in the bladder may obstruction of a ureter, leading to what pathology of the kidney?
Hydronephrosis
How can u screen for Schistosoma haematobium infections to make a Dx?
Look for eggs in urine
Where is the spine on the Schistosoma haematobium?
“T”erminal end
schistosoma haema”T”obium
Which form of Schistosoma has a spine on the lateral side?
Schistosoma mansoni
“M” for “M”iddle
What anatomical defect in females predisposes them to UTI’s?
Short urethra
What “activity” predisposes women to UTI’s?
Bumpin uglies
What leads to more instances of UTI’s in men, circumcised or uncircumcised?
Uncircumcised
How does pregnancy, BPH, renal calculi, tumors, and strictures predispose you to UTI’s?
Obstruction
How does loss of neurological control of the bladder and sphincters predispose you to UTI’s?
↑ residual volumes
This is the reflux of urine form the bladder cavity up the ureters, which can go to the renal pelvis or parenchyma.
Vesicoureteral reflux (VUR)
True or False: diabetes predisposes you to UTI’s.
True
This is the main E. coli strain to cause UTI’s.
Uropathogenic E. coli (UPEC)
What is the virulence factor on UPEC that allows these organisms to inhibit phagocytosis?
Capsular acid polysaccharide (K) antigens
What is the virulence factor on UPEC that allows it to colonize?
P. fimbriae (pyelonephritis-associated pili)
What is the virulence factor on UPEC that allows it to adhere to the bladder uroepithelial cells?
Mannose-sensitive fimbriae (FimH)
What is the virulence factor on UPEC that allows the organisms to cause damage to the kidney membranes?
Hemolysins
What is the virulence factor of Proteus that causes pyelonephritis and stones?
Urease
At what level of organisms/mL on urinalysis do you need to determine a UTI?
> 10^5 organisms/mL
During what part of the stream is urine collected?
Mid-stream
This is the term for collecting urine mid-stream and cleaning the external genetalia which allows you to contain the cleanest and purest result for a urinalysis.
Clean catch
How often do you collect routine specimens for M. tuberculosis?
3 early morning urine samples on consecutive days
How do you collect for a S. Haematobium infection?
the last few mL of a urine sample in the early afternoon after exercise
(get them eggs for brunch!)
What class of drugs is trimethoprim?
Antimetabolite/nucleic acid synthesis inhibitor
What is the increasing problem with trimethoprim?
incidence of resistant strains increasing
What class of drug is co-trimoxazole?
it’s a combo of trimethropim with sulphamethoxazole (also an antimetabolite nucleiuc acid synthesis inhbiitor)
What is the first line treatment for UTI’s?
co-trimoxazole
What is the class of drug for nitrofurantoin?
Urinary antiseptic
When do you use nitrofurantoin?
for uncomplicated UTI caused by E. coli and S. sapro