(HealthDay)—For patients with Streptococcus pneumoniae pneumonia, macrolide-resistance is not associated with worse outcomes, according to a study published online March 25 in the American Journal of Respiratory and Critical Care Medicine.

Catia Cilloniz, Ph.D., from the University of Barcelona in Spain, and colleagues conducted a retrospective, observational study involving 643 adult patients hospitalized with pneumonia with positive cultures for S. pneumoniae from 2000 through 2013.

The researchers found that 22 percent of the patients were macrolide-resistant. Patients with macrolide resistance were less likely to have bacteremia, pulmonary complications, and shock, or to need noninvasive mechanical ventilation. For patients with macrolide-resistant S. pneumoniae pneumonia, there was no increase in the incidence of , the frequency of admission, the need for invasive ventilatory support, hospital length of stay, or 30-day mortality. Furthermore, outcomes were not affected by whether treatment regimens did or did not comply with current guidelines.

"We found no evidence suggesting that patients hospitalized for macrolide-resistant S. pneumoniae pneumonia were more severely ill on presentation or had worse clinical outcomes if they were treated with guideline-compliant versus non-compliant regimens," the authors write.