Question

Select a bacterium, which shows antibiotic resistance in your hospital or your preceptor site. Interpret the specific pattern of resistance for that specific bacterium. For example, to what antibiotics are the bacterium resistant, and what is the evolutionary mechanism or pattern of resistance? What percentage of cases of infection in your hospital need to be caused by resistant organisms before action is taken?

Answer 1

Antibiotic resistance: It is the ability of bacteria or other microbes to resist the effects of an antibiotic. Medicines that help prevent bacterial and fungal infections and infection caused by parasites by retarding their growth or killing them are known as antibiotics. Antibiotic resistance occurs when bacteria change in some way that reduces or eliminates the effectiveness of drugs, chemicals, or other agents designed to cure or prevent infections. The bacteria survive and continue to multiply causing more harm. When these bacteria, fungus and parasites are no longer affected by the use of antibiotics then it is known as antibiotic resistance.

Problem with antibiotic resistance:

The problem with antibotic resistance is that the person will have infection for a longer time and will not get well soon. He might develop serious complications in the future as a result of the infection and more over he will be an active reservoir of the infection and will pass it others as well. The bacteria, fungus and parasites will outgrow their number and the infection will be difficult to control.

MRSA Resistance to Vancomycin:

S. aureus is a leading cause of nosocomial infections, including bacteremia, surgical wound infections, as well as pneumonia. we have case with Nosocomal Pneumonia with MRSA with vancomycin resistance has showed after starting couple days of drug, the hospital setting due to the now intensive use of the many antibiotics, particularly cephalosporin’s, to which the organism is resistant. Vancomycin has been regarded as the first-line drug for treatment of MRSA. Unfortunately there has been an increase in the use of this antibiotic for other infections, such as pseudomembranous colitis due to Clostridium difficult and coagulase-negative staphylococcal infections in hospitalized patients. When this drug was introduced in 1858, it was perceived that there would be no resistance to this antibiotic as resistance was very difficult to induce. However, in 1997 the first stain of S. aureus with reduced susceptibility to vancomycin was reported from Japan. Since then, there has been an increase in the number of cases with both VISA and VRSA (vancomycin-intermediate and vancomycin-resistant S. aureus). This has triggered off alarms in the medical community as S. aureus causes life-threatening infections in hospitalized and non-hospitalized patients.

MRSA Cases percentage:

We determine MRSA infection status and the use of vancomycin in its treatment at a teaching hospital in China. Methods: We retrospectively reviewed 140 cases of MRSA infection that were treated from January 2013 to October 2018. We analyzed the etiology of MRSA infection and the use of vancomycin in these cases. Results: MRSA infection mainly occurred in elderly patients concomitant with a variety of diseases, which incidence was more in men than women. More cases of MRSA infection were encountered in the ICU than in other departments. The positive culture results for MRSA were obtained in the sputum (38.57%), pharyngeal swab (19.29%), blood (5.71%), and wound secretion (11.43%) samples. The MRSA patients were sensitive to vancomycin, with the minimum inhibitory concentration (MIC) being 1 μg/mL in 53.80% of the cases and 2 μg/mL in 44.10% of the cases, respectively. Among the 35 (25%) cases treated with vancomycin, 23 were cured, while 3 died and 7 (20%) were considered as an unreasonable application. Conclusions: MRSA infection mainly appeared in patients admitted to the ICU. The MIC of vancomycin had a tendency to increase gradually

Reference:

Deurenberg RH, Vink C, Kalenic S, Friedrich AW, Bruggeman CA, Stobberingh EE. The molecular evolution of methicillin-resistant Staphylococcus aureus. Clin Microbiol Infect. 2007;13:222–35.