Let's talk about the relative frequencies of
causes of the acute onset of frequency dysuria
or both in young women.
The first thing a physician needs to do in a woman who complains
of dysuria is to exclude vaginitis and Herpes genitalis.
That accounts for perhaps 10% of these symptoms.
They would then get a urine culture.
Most cystitis is associated with
greater than or equal to 10 to the 5th bacteria per mL of urine.
But some women have these symptoms
and have less than 10 to the 5th bacteria per mL.
So what we call them is having the acute urethral syndrome,
and that happens in a sizeable minority of women.
So some of them actually do have bacterial urinary tract infection --
Others have a sexually transmitted chlamydial infection -- 8%.
And the rest, we're just not sure what causes those symptoms.
But to make a presumptive diagnosis of cystitis,
you need to demonstrate the presence of pyuria.
That means greater than 10 white cells per microlitre
of mid-stream urine in a counting chamber.
Now counting chamber is not available to all the physicians,
so more than 5-10 white cells per high power microscopic field in centrifuged urine.
There are sort of automated test like the urine dipstick test
which test for the presence of leukocyte esterase,
one of the enzymes that's present inside of neutrophils.
If that's positive, it has a sensitivity of 75-96%,
and a specifity of 94-98%.
So we often use that.
Then there's the microscope,
and I want to emphasize the first one -- microscopic hematuria.
Now think about the bladder in cystitis, it's going be inflamed.
There's inflammation there with evidence of the white cells
and so it's probably going to be red on the inside
and some red cells are going to get into infected urine.
The point I'm trying to make is that if a woman has symptoms of cystitis
but no microscopic hematuria,
it might be another diagnosis.
It might be vaginitis,
It could be something else.
The urine culture most of the patients have,
more than 10 to the 5th bacteria per mL
but some have fewer than 10 to the 5th.
The other thing is that the Gram stain of uncentrifuged mid-stream urine
can give you kind of a poor man's result of culture.
What I mean by that is if you see 1 microorganism in every microscopic field
because of the magnification
that equals about 10 to the 5th organisms per mL
which would be in keeping with the diagnosis of a urinary tract infection.
So what would we try to do about with patients with cystitis?
One of the time-honored therapies is to hydrate them.
That does rapidly decrease the counts of bacteria,
but after the hydration is over, those counts return to the baseline.
What about urinary analgesics?
They've really not been shown to have much benefit at all.
So our antibiotic choices should have good activity against the offending pathogen,
but the least effect on vaginal and intestinal flora.
Remember clostridium difficile and antibiotic colitis,
we don't want any part of that.
So we want to choose fairly narrow spectrum agents
like nitrofurantoin, fosfomycin, trim/sulfa or pivmecillinam.
Fluoroquinolones should be held in reserve
because there's increasing incidence to those valuable drugs
all over the world.
Now for women who have recurrent cystitis
and remember a sizable minority do,
what we generally recommend is TMP/SMX,
fluoroquinolones after intercourse.
Another thing that can be done is have the woman void after intercourse.
For a long-term prophylaxis in women who have
several episodes a year that interfere with her employment
or activities of daily living,
we sometimes recommend nitrofurantoin or TMP/SMX
or a fluoroquinolone, if necessary.
And that brings me to the end of my discussion of cystitis.
Thank you very much for your attention.