From: jrfox@no.spam.fastlane.net.no.spam (Jonathan R. Fox)
Newsgroups: sci.med
Subject: Re: need info on pediatric UTI (male)
Date: Wed, 24 Mar 1999 16:12:25 GMT

On Tue, 23 Mar 1999 12:13:31 -0500, matt arend
<matt.arend@alliedsignal.com> wrote:

>We have a 11 month old boy (our first) who tested positive for a UTI.
>We went in for an unrelated visit and happend to take his urine
>specimen.  He did have a fever for a few days, he seems just fine now
>(happy etc).   He's been on amoxicliin and we're now retesting for the
>bacteria...
>
>My questions are:
>How common is the in boys?

Not very common in boys that age.  Occurence of a UTI in a male infant
should prompt investigation for abnormalities in the urinary tract
which could predispose him to UTIs.

>Are there "new" tests - I have heard that current testing is very
>inaccurate.

That depends on what you mean by "current testing."  I am concerned
that the UTI was diagnosed by a specimen of urine you brought in from
home.  How was it collected?  How was it tested?  "Current testing" to
me, for an infant still in diapers, consists of bladder
catheterization using sterile technique, and sending the specimen
immediately for urinalysis, Gram stain, and culture.  Using a catheter
ensures that any bacteria present in the urine can be presumed to have
been in the bladder, not a contaminant.  Collecting the urine by
taping a bag around his penis will contaminate the speciment with
bacteria present on the skin and greatly affects your ability to
interpret the results.  Furthermore, bringing in a specimen that may
have been sitting around for hours at home makes the urinalysis less
accurate.

The "gold standard" in diagnosing pediatric UTI is the culture.  This
is because urinalysis alone may be normal in up to 25% of infants with
a UTI.  Furthermore, apparently "positive" results for infection from
a urinalysis without a positive culture can be caused by other
conditions which are erroneously treated as an infection.

>What are the potential problems associated with this (what causes it?)

Potential problems of recurrent UTI are uncommon but may include
infection of the kidneys with resultant scarring, ultimately leading
to high blood pressure and/or kidney failure.  Another problem may be
that he has an anatomical malformation of the urinary system which can
lead to ureteral reflux, again damaging the kidneys.  Often a UTI in
infancy is the first clue that he has such a malformation.

>Wheter or not he tests pos or neg now, what should we look at to
>determine cause?

Usually after the first UTI in a male infant, an imaging study of the
bladder and ureters called a VCUG (voiding cystourethrogram) to look
for anatomical and functional problems is indicated.  This VCUG may be
either fluoroscopic, which is better at finding posterior urethral
valves, or nuclear, which is better at defining vesicoureteral reflux.
Also, an ultrasound of the kidneys may identify hydronephrosis, double
ureters, or other anatomic problems.  In most cases, these studies are
normal.  But the consequences of missing a true problem justify
performing these studies on all infants with a UTI.

>What are the next steps to determine if this is a problem?

See above.

>How "dangerous" is any of this?

Not very.  Although UTIs in male infants are rare, most of them are
simply fluke occurrences with no implications for the future.
However, given that the UTI may be an indicator of easily managed
problems that can have disastrous complications if not diagnosed
early, the further investigations above are warranted.

--
Jonathan R. Fox, M.D.

From: jrfox@no.spam.fastlane.net.no.spam (Jonathan R. Fox)
Newsgroups: sci.med
Subject: Re: Urine color
Date: Thu, 10 Feb 2000 04:00:13 GMT

On 09 Feb 2000 18:47:08 GMT, nurscm@aol.com (NursCM) wrote:

>>You are quite correct to remind everyone that UTIs are not necessarily
>>painful.  However, there is also such a thing as asymptomatic
>>bacturia, where the normally sterile urine is colonized with bacteria,
>>but without inflammation.  Whether this represents a true infection or
>>simply a condition of no clinical significance is up to debate, at
>>least in pediatric patients.
>>
>>Furthermore, the finding of nitrites in your urine is not diagnostic
>>of UTI.  Did you actually have bacteria grow from a urine culture?
>
>No, the doc didn't do a culture. He just did a dipstick. The only symptom I did
>have was the bad odor. I took Cipro and redipped 7 days later and was clean.
>Also started drinking lots of fluids.

It could easily have been the fluids instead of the Cipro.
Concentrated urine can produce false-positive findings on a dipstick.
I guess we'll never know!

In fact, just today I had a patient provide concentrated urine that
had positive leukocyte esterase on a dipstick, which would imply the
presence of white cells.  However, the microscopic exam showed
nothing.  Dipsticks are not precision diagnostic tools at all -- they
are a rough screening device only.

Of course, my take on this is from the standpoint of a pediatrician.
I would imagine that in practice with adults, use of dipsticks only
might be more prevalent since UTIs are more common and of less ominous
significance.

--
Jonathan R. Fox, M.D.