Possible degradation in the effectiveness of antibiotics in the treatment of human diseases

[Graham Shepherd]

Joan Marie Shields wrote in message <7miqnk$jfm at news.service.uci.edu>...
<snip>

>Actually, there are antibiotics, as well as antibiotics in conjunction
>with sulfa drugs, used to treat a number of parasitic protozon infections.
>For instance, the recommended treatment for infection with Cyclospora is
>a combination of two antibiotics, trimethoprim-sulfamethoxazole (also known
>as Bactrim, Septra, or Cotrim).  Unfortunately, if you are allergic to
>sulfa drugs you're out of luck.  However, infection does tend to be self-
>limiting.
>
>Of course, overuse of these antibiotics will probably lead to the same
>problem that we have with bacterial infections - eventual resistance.
>
>
>
>joan
>--
>Joan Shields       jshields at uci.edu       http://www.ags.uci.edu/~jshields
>University of California - Irvine         School of Social Ecology
>Department of Environmental Analysis and Design
>I do not purchase services or products from unsolicited e-mail
advertisements.

I seem to remember that metronidazole can be used for amoebic dysentery,
too.
Why these drugs work is a mystery to me; the sulfa combination is supposed
to block folate metabolism in bacteria. Presumably we have an alternative
pathway;
I guess some protozoans don't have it and that makes them susceptible.
If so, they would need to evolve the alternate pathway in order to become
resistant.
That sounds a lot more difficult than evolving a single enzyme like
penicillinase.
 Anyone care to speculate on the probability?

Also - where we came in - is there any evidence for clinical use of an
antibiotic against toxoplasma?

GS