1) Bronchitis tends to be caused by bacteria sensitive to antibiotics.
2) Sputum samples are useful in diagnosing the cause of bronchitis.
3) Antibiotics speed the resolution of bronchitis.

In fact, most bronchitis in otherwise healthy individuals is caused
by viruses.  There is little evidence to support using antibiotics
at all in people with bronchitis, and little evidence that sputum
cultures correlate with the etiology of the bronchitis.
--
David Rind

Marty Braff

I'll expand on David Rind's fine response to your question.

First of all, most upper respiratory tract infections are in fact viral,
and require no antibiotics.  If you are diagnosed with "bronchitis",
this too is probably viral, but if you're coughing up lots of green
stuff most practitioners will start an antibiotic...although keflex
(cephalexin) would not be my first choice.  I tend to favor
erythromycin, which will cover the most common "pneumonia" bugs
(pneumococcus, etc.) as well as some weird ones (legionella) and a
common one in {*filter*}agers (mycoplasma).  And it's still quite a bit
cheaper than keflex, as far as I know.
  The reason for not doing cultures is twofold.  First, cultures tend
often not to have a very good yeild, especially when the patient just
spits some sputum into a cup.  It's full of contaminants, and the common
respiratory pathogens may live in the pharyx as commensals anyway.
Also, by the time the culture is closed out (several days) you've
generally been treated.  Sputum culture is generally done in
hospitalized patients who may have unusual pneumonias caused by less
common bugs, and in persons with chronic lung disease.  Your basic
community acquired pneumonia or bronchitis generally doesn't require a
culture.  
  By the way, a culture is pretty cheap.  A few bucks, compared to maybe
forty or fifty for a chest XR if a radiologist reads it.  With respect
to "resistant" bugs, these tend to live in hospitals.  It's
exceptionally rare to see a community acquired pneumonia caused by an
organism with acquired resistance to antibiotics.  However, a person
with a bad cold with a viral bronchitis could easily convince himself
that he has a "resistant" infection when the antibiotic he didn't need
in the first place doesn't cure his viral infection.
--

Joseph P. Pulcini, M.D. ..........."Now can I be a musician, Mom?"
-General Medicine..................."Primum Non Nocere"
-Diving Medicine...................."You bend 'em, We mend 'em"
-Clinical/Surgical Pathology........"The search for truth"
-Lead Guitar........................"A loaf of bread, a jug of wine,
                                    a Strat, and a Marshall"

Personal problem. For two years I have had a problem with my left ear.
The problem manifests itself as though I had been swimming and gotten
water in the ear, except that this doesn't go away. No loss of hearing
(none that I can detect anyway) but movement of the jaw or sometimes
head makes this crackling noise, something like a creaky bed. Only I
can hear it of course. No balance problems, no nausea, no other bodily
changes. After hoping it would go away, I went to my local GP about
eigh{*filter*} months ago. After the usual "Hrmp, I've got more important
diseases like AIDS, heart patients, etc" he looked in the ear--no ear
wax, no obvious problems. He suggested a minor infection of the
Eustacian (sp?) tube and said to try Sudafed--worked for him,
allegedly. I tried, no change! Hey, it's not life threatening and
unless I'm doing something quiet, like typing this, I don't even
notice it, but I'd like to get rid of it.

How does this relate to sputum analysis? Well, every time I get a cold
(maybe twice a year) it's a disaster. Most other people a cold lasts a
week or so. For me a cold lasts three or four, not counting the
cough--productive in the early morning of small quanities of white
phlegm--which may go on until I get the next cold. I also have a
feeling that there is phlegm in the back of my thoat--sensation of
swallowing something all the time. To my mind they're all
inter-related. Cure the cough, you'll cure the ear problem, but since
none are serious, the difficulty is to get someone to pay attention.

Any suggestions as to a) what the problems are; b) a course of
treatment; c) how to get the GP to pay attention.

BTW, please don't suggest to change GP's. This guy is good for
something: he'll write any prescription you ask. Are you aware how
effective Vallium + alchohol is for the avoidance of jet lag? But
that's another story...

--
Patrick Riley

But there's also another problem.  You can't always identify a cause, no
matter how good the lab is and how many sputum samples you give them.
Life isn't always black and white.  Bacteria don't come with big flashing
neon "I'M BAD" signs; some bacteria are bad sometimes, harmless other
times, and finding them in a sputum sample isn't informative.  As I say,
sometimes you simply *can't* find a cause.  Deal with it.

What can happen, though - and often does - is that bacteria can colonize a
respiratory tract that's already weakened by the virus.  So what you see,
on the outside, is a continuous, single disease.  What's happening on the
inside is that there were two diseases: a virus, which was cleared up by
your immune system, and then a bacterial disease - or perhaps even two
bacterial diseases, or maybe one virus, a second virus, a bacterium, and
then another virus.

So, you say, why not treat for bacteria, period, if bacterial infections
will follow viral infections?  The answer is that in most cases they
don't.  That is, because most bacterial infections are prededed by a viral
infection, does not imply that most viral infections are followed by a
bacterial infection.  Thus if you treated all viral infections with
antibiotics, you'd be overtreating the great majority of them.  And what
happens there is, first, excess cost; but, more important, antibiotic
resistance.  In the long run you're probably more likely to have a serious
problem if you follow this treat-at-first-sight approach.

Ian
--

      "-but as he was a York, I am rather inclined to suppose him a
       very respectable Man." -Jane Austen, The History of England

Your response was not helpful.

--
Patrick Riley

If you want useful advice from Usenet, ask for, say, treatments for a
specific disease; or ask for the epidemiology of a specific disease; or
ask how viral upper respiratory disease can lead to bacterial respiratory
disease.  You can get useful answers for that.  You cannot get a useful
diagnosis by describing your symptoms.  

Now, you may like this doctor for his incompetence, and you obviously do.
You therefore have a choice:  (1) Settle for an incompetent doctor, so you
can drug yourself up at will, thus running the usual risks of those who
self-medicate.  (2)  Go to a competent doctor, who will not permit you to
harm yourself by irresponsible self-medication, and you might get an
accurate diagnosis.  The choice is up to you.  But once you make that
choice, you're being a hypocrite to whine about not getting a competent
diagnosis.

Deal with it.

Ian
--

      "-but as he was a York, I am rather inclined to suppose him a
       very respectable Man." -Jane Austen, The History of England

<snipped lots of patronizing arrogant blah blah>

I'm sorry, I didn't make myself clear. As an ex-vet, immunologist, and
virologist, just what useful information did you think you had to
contribute to a post that required a practical knowledge either as a
patient, GP or ENT guy? If you haven't anything worthwhile to say,
just {*filter*}out!

BTW my dog has a hot spot on his right front paw (the vet says so and
I agree). Any suggestions? (might be closer to your abilities).

--
Patrick Riley

The only way to be sure you are not eating anything
you are allergic to is to not eat anything at all.

What I'm trying to say is that I'm not trying to claim that, in theory, a
viral bronchitis (or rhinitis or pneumonia) *could not* be persistent.
(Take a moment to review those triple negatives.)  What I am saying is
that human viral causes of bronchitis (and rhinitis and pneumonia) *are
not* persistent pathogens.  It's pointless trying to extrapolate from hep
B to rhinovirus; all it lets you do is say that theoretically it could be
the case.  It tells you nothing about what *is* the case.

The closest to a persistent bronchial virus in humans would be the
adenovirus family.  Adenoviruses cause, among other things (and depending
on many factors) respiratory tract disease ranging from no symptoms (most
common) to typical cold symptoms to severe pneumonia (mainly in
immunodeficient people).  Although the *disease* caused by adenoviruses is
generally self-limiting and of short duration, the virus is pretty good at
persisting for long periods - months - even after the symptoms are
resolved.  But this isn't an exception to my statement that in humans
respiratory viruses cause short-lived disease, because the virus doesn't
cause the disease in the persistent phase.  (Adenoviruses were first
identified, in the '50's, by isolating a virus from the adenoids of a
*healthy* individual.)

Epstein-Barr virus can also cause pneumonia, in rare circumstances, and
it's a persistent virus; but again the pneumonia per se isn't persistent.
(It's also very rare, and I don't think there's been any cases of
bronchitis associated with EBV.)  There are a handful of other persistent
viruses that can very rarely, and mainly in the immune compromised, cause
respiratory diseases.  It's been suggested that respiratory syncytial
virus can cause persistent respiratory disease in humans, but the evidence
for this is is pretty weak, and it seems most likely that this is at most
a rare occurence - most RSV disease resolves pretty quickly.

So to summmarize, when we're talking about upper respiratory disease in
humans, if it persists for more than, oh, say, a week or ten days, you're
very unlikely to be dealing with a single viral infection.  

Ian

--

      "-but as he was a York, I am rather inclined to suppose him a
       very respectable Man." -Jane Austen, The History of England

Marty Braff

If a bug is cultured what is the likelyhood that it is actually
causing the infection, and not an innocent bystander?

Marty Braff