A woman in the United States killed a bacterium that is resistant to all antibiotics


    A group of resistant enterobacteria. Photo: U.S. Centers for Disease Control and Prevention

    Before the invention of antibiotics, it was common that people did not live to be 30 years old, dying from infectious diseases. If you do not invent new antibiotics, then these times can come back.

    Experts know that as a result of natural selection through random mutations, microorganisms develop resistance to individual antibiotics. Microbes are able to transfer genetic information about antibiotic resistance through horizontal gene transfer. This is a direct demonstration of evolution in living nature, when a living creature changes its characteristics in order to become completely resistant to harmful environmental conditions. In this case, the harmful environmental conditions are human activities. Scientists believe that antimicrobial resistance manifests itself as a result of the gradual accumulation of mutations over time , although it can also occur as a result of a targeted change in the genome of the pathogen.

    Whatever the cause of antibiotic resistance, such organisms pose a major threat to human life. These germs are very difficult to kill. The darkest thing is that antibiotic-resistant microbes can multiply over time - and the number of deaths will increase. According to the pessimistic forecast of doctors, by 2050, such bacteria will kill 10 million people a year around the world. In the coming decades, these "superbacteria" may become one of the main causes of death on Earth, ahead of cancer, death in traffic accidents (1.2 million people a year), and, of course, all wars and terrorist acts combined.

    According to doctors, now microbes partially resistant to antibiotics kill about 700 thousand people a year.. But in almost all cases it was possible to choose an effective drug. Microbes resistant to absolutely all antibiotics are very rare. There is always a chance that in fact the patient could be saved - maybe the doctors used the antimicrobial or antibiotic incorrectly, did not have time to choose the right medicine.

    One of the most studied cases with proven death of a patient from a resistant microbe is documented in a scientific article published a few days ago in the American medical journal Morbidity and Mortality Weekly Report (MMWR) .

    On August 18, 2016, an infected woman was admitted to a hospital in the US city of Reno (Nevada) with a preliminary diagnosis of “Systemic Inflammatory Response Syndrome”, presumably due to infection through gray on her right hip.

    On August 19, 2016, analysis of a sample taken from the area of ​​infection determined the presence of the bacterium Klebsiella pneumoniae , Friedlander's bacillus. This gram-negative facultative anaerobic rod-shaped bacterium is one of the common causative agents of pneumonia, as well as some other infectious diseases. The woman was quarantined in an isolated room. On August 25, 2016, a patient with an infection who is resistant to all known antibiotics was reported to the local disease control and prevention center.

    An examination of the medical history showed that a patient over 70 years old returned in early August after a long trip to India. During the two years before, she was hospitalized several times in India in connection with a fracture of her right thigh, followed by ostomyelitis, the last time - in June 2016.

    The patient developed septic shock, death occurred in September 2016.

    Testing for antibiotic resistance showed that the bacterial sample is resistant to 26 antibiotics, including all aminoglycosides and polymyxins, and partially resistant to tigecycline, a special kind of antibiotic designed to fight resistant microbes. Colistin and fostomycin were tested during testing. Tests showed pathogen sensitivity to fosfomycin at a relatively low inhibitory concentration. Unfortunately, fosfomycin is allowed in the US only for oral use in the treatment of uncomplicated cystitis, although it can be administered intravenously in other countries. All drugs approved for use in the United States were powerless against this pathogen.

    Particularly noteworthy is the lack of response to colistin. The bacterium becomes resistant to this drug when it has the mcr-1 gene. Recently, scientists note that due to the use of colistin in pig farms in China, bacteria have developed resistance to this antibiotic, and now the mcr-1 gene is found in the genome of a large number of microbes .

    Specialists at the Center for Disease Control and Prevention note that they constantly monitor the occurrence of resistant bacteria, but the detection of microbes that are resistant to absolutely all antibiotics is extremely rare. Among more than 250 cases, which were analyzed over the entire observation period, more than 80% of the samples were supposedly vulnerable to at least one type of aminoglycoside, and 90% to tigecycline.

    The Center for Disease Control and Prevention warns of the need to take appropriate quarantine measures in the event of the detection of such bacteria in order to prevent the spread of infection. Additional safety precautions should be taken in relation to patients who have recently arrived from India or other regions where antibiotic-resistant microorganisms are known to exist.

    The problem is very serious. It will be very difficult to fight an infectious disease if the pathogen is resistant to all known antimicrobials. “I think this is alarming. We have been relying on antibiotics for so long. But it’s obvious that microbes can often develop resistance faster than we can produce new drugs, ” says Alexander Kallen, an employee at the regional center for disease control and prevention.

    The situation is complicated by the fact that the testing procedure for new antibiotics takes a very long time, and some pharmaceutical companies completely abandoned the development of new drugs. For example, Cempra Pharmaceuticals has not received FDA approvalon your new antibiotic due to possible side effects on the liver. For about 21 years, the pharmaceutical company Paratek Pharmaceuticals has been waiting for the approval of its new antibiotic omadacycline, its trials are ongoing.

    The medical report was published on January 13, 2017 in the journal Morbidity and Mortality Weekly Report (doi: 10.15585 / mmwr.mm6601a7).

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