What is Antibiotic Sensitivity?
Sensitive: Record as (S). Zhongmin: recorded as (I). Resistance: Recorded as (R).
- No bacteria were found in normal people's blood, urine, cerebrospinal fluid, pleural fluid, pericardial fluid, and peritoneal fluid. There are three ways in which bacteria are sensitive to antibiotics. (1) Diffusion agar plus various nutrients required by bacteria, melt the culture medium, pour it into a sterile Petri dish, cool, and condense into a flat surface or plate (plate). At this time, the bacterial solution containing a small amount of bacteria is coated on the plate, and the bacteria will be split on the plate after culture. If antibiotic paper is added to the culture medium of the plate in advance, the drug spreads in the medium, which inhibits the (Bactericidal) bactericidal effect, forming a suppression circle of not long colonies. The size of the inhibition circle reflects the extent to which an antibiotic inhibits the bacteria. (2) Dilution method The commonly used drug sensitivity dilution method can be divided into two methods: test tube dilution method and agar dilution method: The test tube dilution method first makes a series of multiple dilutions of the test antibacterial drug, and then each test tube is added with the appropriately diluted test bacteria solution, and shake After the culture is observed, the sensitivity of the test strain is the minimum inhibitory concentration (MiC) tube of the antibacterial drug. The agar dilution method adds different doses of antibacterial drugs to quantitative agar medium that has been melted and cooled to 45 ° C, mixes well and pours into sterile plates, that is, a medium containing a decreasing drug concentration. On this medium, after the culture is observed, the growth of the tested bacteria, the minimum drug inhibits the growth of bacteria, that is, the minimum inhibitory concentration (Mic). (3) Automatic analysis in France using the AUTOBAC instrument for bacterial drug sensitivity determination. The instrument uses the ring drug low film, the culture shaker and the photometer host to test the data. According to drug resistance, medium resistance, sensitivity, and the minimum inhibition The bacteria concentration is printed. This instrument is only suitable for the determination of aerobic and facultative anaerobic bacteria, and is not suitable for the testing of obligate anaerobic bacteria and mycobacterium tuberculosis.
- Name
- Bacteria sensitivity test
- category
- Microscopy
Normal value for bacteria sensitivity test to antibiotics
- Sensitive: Record as (S). Zhongmin: recorded as (I). Resistance: Recorded as (R).
Clinical significance of bacteria sensitivity test to antibiotics
- It reflects the degree of bacteriostasis of an antibiotic to this bacterium. Clinically guide physicians in the proper use of antibiotics and avoid re-use of antibiotics that have developed resistance.
Precautions for susceptibility testing of bacteria to antibiotics
- (1) The test bacteria should be highly sensitive to the antibiotics being tested. (2) The test strains issued by the Institute for Drug Control are freeze-dried products, stored in a refrigerator at 5-8 ° C, and generally can be stored for 1-3 years. (3) During the experiment, be sure to establish the "concept of antibiotic-free operation". (4) Sulfonamide-free agar plates are used for sulfonamides. Proteins can make sulfonamide ineffective.
Diseases related to bacteria sensitivity test
- Septic shock, mediastinal abscess, suppurative uveitis, retroperitoneal abscess, lung abscess, impetigo, bacterial vaginitis, abscess, chronic suppurative otitis media, otogenic brain abscess
Symptoms related to bacterial sensitivity test to antibiotics
- Baiji, uveitis, brain abscess, toothache, allergic dermatitis, oral ulcer, abscess, chest pain, headache, ulcer