Click for larger
picture |
We can take a look at
surveillance data to see whether worrying about levofloxacin-resistant S. pneumoniae is
justified. Several large surveys are listed; in each you can see that the prevalence of
resistance to levofloxacin is quite low. Thus there should be no problem using the drug to
cure people. However, when you ask whether the prevalence of resistance has been
increasing, you see that it has. For example, in the first set of data the prevalence
doubled between 1994 and 1999. In the next set it went up by a factor of 8 between 1997
and 2000. Of course we need to be cautious with these numbers because they are so small.
Indeed, the increases are unlikely to be statistically significant, and the authors of
these studies do not emphasize increases in resistance. But these data do suggest that we
should watch next year's data carefully. At the single-patient level studies from Don
Low’s group show that levefloxacin resistance can develop in a single patient during
levofloxacin therapy. |