Very often, before appointing treatment and prescribing appropriate medications, doctors check a person for sensitivity to antibiotics . This is done in several ways.
What does sensitivity to antibiotics mean?
So, the detection of sensitivity or resistance of microorganisms to antibiotics is necessary for the appointment of the correct method of treatment. So, for example, if the causative agents of the infection are resistant to a particular drug, then the treatment will simply not have the desired effect. There are several forms of resistance:
- sensitive;
- moderately sensitive;
- stable.
Sensitive microorganisms die immediately after the administration of small doses, and moderately sensitive - at certain concentrations. In this case, resistant can die only when interacting with a large amount of antibiotic, which can not be introduced into the body, and, therefore, it is necessary to seek an alternative way of treating and eliminating the disease.
Methods for determining susceptibility to antibiotics
There are several ways to determine the sensitivity of microorganisms to antibiotics:
- method of successive dilutions in a liquid nutrient medium;
- method of diffusion into agar;
- accelerated method.
Most often the sample for sensitivity to antibiotics is carried out by the method of determination in physiological fluid. In this case, the process of processing integrated plates with different concentrations of antibiotics is used. This method is used to determine patients with cancer in order to confirm or deny the effectiveness of the prescribed drugs in chemotherapy .
The analysis for sensitivity to antibiotics by the diffusion method is almost as common as the first. At the same time, he gives only a qualitative answer, whether or not there is resistance.
Thanks to the development of microbiological technologies, accelerated diagnostic methods have appeared, which provide complete and detailed information. This is very important when prescribing medications, as well as when time does not stand, and you should start treatment as soon as possible.
Sometimes it happens, when the results and the above methods of research are not enough. In this case, a minimal bactericidal concentration is deduced, which is capable of destroying the causative agent of the infection, only it occurs for a certain period of time.