First off, I think you need to more clearly define terms.
There are two types of Creationists; Old Earth and New Earth. NE Creationists believe in a literal 6 day creation. OE Creationists believe the word "yom" in Genesis that is usually translated as "day" is more accurately translated as "a period of time" or "an age" like "The Age of Chivalry".
Also, there are 4 types of evolution. Micro (small adaptations of a species over time), Macro (a change that turns one species into another species) and Darwinian Macro (that through an unguided and random process, there are changes that turn one species into another) and punctuated equilibrium (major evolutionary jumps all of a sudden as opposed to a slow, Darwinian type of process).
All creationists believe in microevolution. This is also called "husbandry" is is a very well established science. Creationists have no problem with this whatsoever.
NE creationists have an issue with macro evolution due to the time requirements which then call into question their position that the universe is only a few thousand years old. Most OE creationists have no problem with this since God says he created the universe, but did not say how or exactly how long it took, due to the translation of the word "yom".
Almost all creationists disagree with Darwinian Macroevolution since it rejects the notion of a God in control of the process.
Punctuated Equilibrium tends to make no claim as to whether there is a God or not, nor speaks to the question of control over the process. There is still a fair amount of work to be done on this, but it is promising.
Now that we have the terms right, let me answer your question. Yes, I think it is fair to say that creationists do believe in drug resistant bacteria. However, we have never seen a drug resistant bacteria evolve into a new species. It is still a bacteria. There has not been any solid evidence of any species changing from one to another.
Your claim of macro evolution being a series of micro evolutions is only partly correct. Darwin stated that, should there be a biological system that could not be arrived at through a series of small evolutions, that his theory would be wrong (the problem of irreducible complexity) . Over the past 100 years or so sine he wrote that theory, we have come across numerous systems that cannot be reduced; DNA, protein creation, sexual reproduction, the eye, etc. In general, microbiology has disproved Darwinian Macro.