Researchers Find Drug Combo Works Against Multidrug-Resistant Bacteria

Antibiotic-resistant bacteria are a growing problem all over the world. Part of the problem is that over-prescription of antibiotics has caused the bacteria to mutate and develop a resistance to the agents being used to treat them. In fact, according to the Centers for Disease Control and Prevention (CDC), more than 2 million people are infected with these bacteria every year, and upwards of 23,000 patients die because of these drug-resistant infections.

Research recently published in Nature Microbiology, however, has shown that utilizing antibiotics in combination with other medications could be the key to stopping antibiotic resistance.

Traditional treatments for antibiotic-resistant infections consist of spending a lot of time trying out every antibiotic in the book. If those fail, the only options are to treat the symptoms, do everything that can be done to bolster the patient’s immune system, and hope the body can fight off the infection on its own. Combination therapy, however, could potentially change that treatment plan.

When pairing an antibiotic with an antiprotozoal medication called pentamidine, the antimicrobial part of the treatment can breach the outer shell of the bacteria.

Pentamidine alone is used for the treatment of Pneumocystis jiroveci pneumonia, but when used in conjunction with an antibiotic, it has proven successful in treatments against three of the most prevalent drug-resistant bacteria:

• Acinetobacter baumannii: Which causes a variety of diseases and most commonly becomes a problem in hospital settings for patients with compromised immune systems.
• Enterobacteriaceae: The family of bacteria that includes gastrointestinal pathogens such as Salmonella and Escherichia coli.
• Pseudomonas aeruginosa: Similar to Acinetobacter baumannii in that it can cause a variety of diagnoses and is most commonly found in patients who are hospitalized for more than a week.

Right now, successful treatments have only been completed in laboratory settings and on mice, but researchers are excited to continue their trials through the pre-clinical stage and eventually into human trials.

There are some alternative treatments available to treat the growing number of drug-resistant bacterial infections. Bacteriophages, for example, are being used overseas to treat bacterial infections that have resisted other forms of treatment. Bacteriophages are selected for the specific infection and are then introduced into the body to consume the "bad" bacteria. Scientists have also recently studied phages to learn how bacteria communicate with each other, finding that “each phage species broadcasts on a specific molecular ‘frequency’ that can be ‘read’ by phages of its own kind, but not by other phages.”

There are several anecdotal stories about the success of these treatments, but they have not yet been tested or approved by the US Food and Drug Administration (FDA). Getting these treatments approved by the FDA could be nearly impossible; however, because each bacteriophage and combination of phages would have to be individually trialed, tested, and approved. That process could take decades.

While new innovative treatments may become available in the future, right now the ray of hope provided by combination therapy might be the best option to help us fight the growing problem of drug-resistant bacteria.