Antibiotic Resistance

What’s the Problem?

Antibiotics are part of a group of medications called anti-microbials, meaning against microbes (very tiny germs including bacteria, viruses, fungi, and parasites). Microbes that cause diseases are called pathogens—also sometimes referred to as germs or bugs. Generally, antibiotics are used to kill pathogens. Antibiotic resistance happens when pathogens are not killed by the antibiotic.

Since the discovery of antibiotics in the 1940s, they have become one of the most commonly used medications worldwide – in humans and animals. Although these medications have saved millions of lives, some bacteria have developed resistance to one or more of them. There are several reasons why resistance develops:

1. Worldwide, widespread use of antibiotics. Careful use of antibiotics is important to decrease the risk. Antibiotics should be given at the right time, for the right dose and duration. Unfortunately, they are not properly prescribed or taken nearly 50% of the time.
2. Antibiotics kill the good bacteria that live in our guts and help protect us from infection. Loss of good bacteria allows Clostridium difficile (C. Difficile) to emerge and cause problems. C. difficile is one of the CDC’s top 18 problem bacteria. It causes severe diarrhea and is linked to about 14,000 deaths in the U.S. annually.
3. Use of antibiotics in animals that become human food. Antibiotics should only be used to treat sick animals.
4. Spread of resistant bacteria from person-to-person, contaminated environments, or medical equipment is another risk for infection.
5. Bacteria that have naturally occurring resistance to antibiotics. Those germs can share their resistance abilities with other bacteria, which promotes spread.

Bacteria that have resistance to available antibiotics have been nicknamed, “Super Bugs.” The CDC compiled a list of the 18 most-feared resistant bacteria. One of the most dreaded is carbapenem-resistant Enterobacteriaceae (CRE), because carbapenems are one of the last lines of defense to fight serious infections.

The CDC, along with other federal agencies, is working to develop a plan for dealing with super bugs. Time is of the essence. In the U.S., antibiotic-resistant bacteria causes infections in more than 2 million people and nearly 23,000 deaths annually.

Who’s at Risk?

Anyone can become infected with antibiotic-resistant bacteria; however, some people are more at risk than others. The risk is greater for people with weakened immune systems, such as those with cancer, diabetes, end-stage kidney disease, and HIV/AIDS.  Also at risk are those receiving certain medications such as chemotherapy or agents that suppress the immune system.

People who have had complicated surgeries (e.g., cardiac by-pass and joint replacements) are also at risk.

Can It Be Prevented?

People can help reduce the risk of getting an infection due to antibiotic-resistant bacteria for themselves and their families with the following tips:

• Wash hands, especially when handling raw eggs, fresh produce, and uncooked meat.
• Keep vaccines up-to-date for all family members. This helps decrease the risk of getting an infection and thus, decreases the need to take antibiotics.
• Follow safe food handling practices.
• Keep water safe from germs.
• Use protection against sexually transmitted diseases (STDs) and avoid spreading STDs.

When ill:

• People should only use antibiotics to treat an infection for which they can help. For example, viruses cause most colds, flu, sore throats, and bronchitis. Antibiotics do not treat viruses. Taking antibiotics when they are not needed increases risk of developing antibiotic-resistant bacteria.
• Patients should talk to their medical team about their care if hospitalized.  In addition, patients should feel empowered to remind their doctors and nurses to wash their hands before examining them.
• Patients should also watch for signs or symptoms of a new infection while in the hospital. For example, redness or pus at a surgical site suggests an infected wound and bloody diarrhea may be a sign of C. difficile infection.

Bottom Line

• Be smart about using antibiotics. Only take antibiotics when treating an infection for which they can help and take them as prescribed.
• Decrease exposure to resistant bacteria with good hand washing and safe food handling.
• Avoid STDs and minimize exposure to contaminated environments, including in hospitals.
• Make sure vaccines, including annual flu shots, are up-to-date for all family members.

Case Example

James, a 60 year-old movie executive, was having pain in the middle and upper right part of his abdomen after meals. Sometimes he would also have nausea and vomiting with the pain. He consulted with his internal medicine doctor, who referred him to a local university hospital gastroenterologist (an intestines specialist). Gallstones were seen on James’ abdominal ultrasound. Because of concern that one of the gallstones was blocking the common bile duct, James underwent a procedure called endoscopic retrograde cholangio-pancreatography (ERCP) using a duodenoscope (pronounced du•o•de•no•scope). In this procedure, a devise was inserted down his throat, into the esophagus and through his stomach to visualize the ducts emptying waste products from his gall bladder and liver. The procedure was uneventful and James was discharged later that day.

Two days after the procedure, James began having fevers, chills and lightheadedness.  He called his internist who sent James to the ER. Upon arrival in the ER, James was sweaty and pale. His heart rate was racing at 140 beats per minute and his blood pressure dropped to 80/60. The ER staff was concerned that he had sepsis, an overwhelming infection in his blood. They promptly took his blood to check for infection and administered IV fluids to help correct his low blood pressure. They also gave him broad-spectrum antibiotics to treat the usual infections after a procedure. James was admitted to the intensive care unit, but continued to deteriorate. Despite treatment, James died later that evening. The next day, the microbiology lab identified CRE bacteria in his blood sample.

Recently a cluster of carbapenem-resistant Enterobacteriaceae (CRE) cases was identified at a prestigious Los Angeles university hospital. In that investigation, exposure to duodenoscopes was associated with transmission of CRE. Because of its intricate design, duodenoscopes can be challenging to clean. An investigation by the CDC found no breech in protocol for cleaning procedures of the duodenoscopes.