Spreading US Macrolide Resistance

“A viral co-infection rate [greater than] 30% supports the use of multiplex testing for viral and bacterial pathogens in children with respiratory infections of uncertain etiology,” the researchers wrote.

They noted that their study provides the most accurate estimate of US macrolide resistance to date. Previous research showed the figure ranged between 8% and 10%, but those data were limited to individual case reports, clusters, outbreaks, or single geographic locations. Macrolide resistance has been reported in the United States since 2008 and since 2000 in Asia, where resistance is now greater than 90% in some parts of China and Japan. Prevalence ranges from 2% to 26% in European countries and is 30% in Israel.

In the United States, the investigators wrote, macrolides including erythromycin and similar agents should continue to be the drug of choice to treat children with M pneumoniae respiratory infections. The investigators advised clinicians to use the drugs judiciously and be vigilant for poor treatment response. They also urged ongoing surveillance for macrolide-resistant M pneumoniae and the development of treatment alternatives to tetracycline and fluoroquinolones.