Rifampicin resistance allows bacteria to survive treatment with this antibiotic due to mutations in their genetic code. Patients who take the drug to treat an infection will not be able to achieve complete control of the infection because some bacteria will persist. In the lab, rifampicin resistance can create problems with bacterial cultures, because it allows organisms to survive on plates treated with the antibiotic to prevent the growth of some species. The phenomenon of antibiotic resistance has important implications for medical research and microbiology.
This antibiotic targets Ribonucleic Acid (RNA) polymerase to prevent protein synthesis, killing organisms exposed to it. Over time, bacteria can develop genetic mutations that can eventually make them immune to rifampicin. These may start among a small percentage of the population, but as the length of exposure to the antibiotic increases, more and more organisms can resist it. Patients may spread their infection to other people, and the bacteria can exchange genetic information with others to disseminate the resistance through the population.
Tuberculosis is commonly treated with rifampicin, along with Hansen’s disease and some other bacterial infections. Bacteria have varying levels of natural rifampicin resistance which can be amplified with extended antibiotic treatment. Patient compliance can also be an issue; if the patient doesn’t adhere consistently to the drug regimen, it can increase the chances that some resistant organisms survive and live to pass their genes on to others.
To address rifampicin resistance, the drug may be provided in combination with another medication that works differently. This ensures that organisms not killed by one will be mopped up by the other. Medical providers may also request cultures to test for susceptibility before they decide on which drugs to give, in case the bacteria are resistant to multiple drugs. In these cases, other antibiotics from a different family of drugs may be necessary to treat the patient adequately.
In the lab, studies on rifampicin resistance look at how it develops and spreads through colonies. Cultures may be grown with several antibiotics on the plate to see how the bacteria respond. This can allow the researcher to identify resistant organisms for further study, or to determine which antibiotics would be most effective in treatment for a given patient. If bacteria grow aggressively on the section of a plate treated with rifampicin, for example, this indicates the drug would not be effective for the patient’s infection and another drug should be considered.