Antibiotics Helped Fight Resistant Stomach Bug

Carbapenem resistant enterobacteriaceae infection treated with gentamicin and colistin in Israeli study

(RxWiki News) Infections can be concerning, but that concern becomes much more serious if the infection is resistant to treatment. Researchers are racing to find ways to treat these resistant infections.

Researchers in Israel looked at a certain type of drug-resistant bacteria common in hospital settings, and explored treatment using two medications — gentamicin and colistin.

These researchers found that carriers of the bacteria who received either medication were more likely to get rid of the bacteria than were those who received neither medication.

"Wash your hands carefully, especially before you eat."

This new study was led by Ilana Oren, MD, of the Infectious Diseases Unit at the Rambam Health Care Campus in Haifa, Israel and focused on carbapenem-resistant Enterobacteriaceae (CRE).

CRE are difficult-to-treat types of bacteria due to their resistance to antibiotics, explained the US Centers for Disease Control and Prevention (CDC). Infections with CRE often develop among those already ill in a health care setting. According to the CDC, some reports have estimated that CRE can lead to death in as many as half of all cases.

Dr. Oren and team wanted to explore the results of treating CRE-colonized patients with the oral forms of a type of antibiotic called gentamicin and an antibiotic called colistin.

These researchers followed 152 patients, ranging in age from 21 to 99, at the Rambam Health Care Campus in northern Israel. These patients had been found to be carriers of CRE, meaning that they tested positive for the bacteria in a swab test.

Of the patients, 50 received one of three treatments, depending on the type of CRE found in their systems. Gentamicin was given to 26 patients in doses of 80 milligrams (mg) four times a day, 16 patients received 100 mg of colistin four times a day and both medications were given to eight patients.

The medications were given to patients until the CRE was eradicated — meaning that they tested negative for CRE in three consecutive tests — or until 60 days, whichever of the two came first. These treatment patients were followed for an average of 33 days.

An additional 102 CRE carriers did not consent to use of one of the medications studied, and were followed for as long as possible without any of the treatments (an average of 140 days).

CRE was eradicated in 42 percent of the gentamicin group, in 50 percent of the colistin group and in 37.5 percent of those who took both medications.

In comparison, only 7 percent of the group receiving none of the treatments experienced "spontaneous eradication" — meaning that they reached eradication without any treatment.

The authors of this study reported that no serious medical events were seen in any of the patients. 

"Oral antibiotic treatment with nonabsorbable drugs to which CRE is susceptible appears to be an effective and safe for eradication of CRE colonization and, thereby, may reduce patient-to-patient transmission and incidence of clinical infection with this difficult-to-treat organism," Dr. Oren and team wrote.

This was a small study, and further research is needed to confirm the findings. It is important to note that neither oral gentamicin nor oral colistin are currently approved to treat CRE infections in the US. 

This study was published in the December issue of the American Journal of Infection Control. No conflicts of interest were reported.

Review Date: 
November 26, 2013