The impact of medical treatments on the sinus microbiome is of great interest to both clinicians and researchers. Some studies have not found a link between the use of topical saline or intranasal steroids and altered microbiome composition. (Curr Opin Otolaryngol Head Neck Surg. 2016;24:20–25.) Other studies have linked oral and topical antibiotics to changes in the microbiome.
Explore this issue:March 2019
A retrospective chart review of 22 adults, conducted by Dr. Chang and others, looked at the microbiomes of CRS patients before and after treatment with topical mupirocin. Before treatment, the microbiota of most patients were dominated by gram-positive bacteria. After treatment, gram-negative bacteria dominated. Additionally, Corynebacterium, a genus of bacteria that’s been noted to dominate the microbiota of some patients with CRS, was more common in patients treated with mupirocin (JAMA Otolaryngol Head Neck Surg. 2015;142:1–5).
“Antibiotic therapy can be a double-edged sword,” Dr. Chang said. “We often put people on longer courses of high-dose antibiotics because that’s what we’ve been taught. But once you start talking about therapeutics, you have to understand there’s a balance. We’re beginning to recognize that big hammer-type solutions can often create more problems down the line.”
Although some people have already begun advocating for the use of topical antibiotics to decrease the preponderance of pathogenic bacteria in the microbiome and probiotics to replenish “good” bacteria, Dr. Chang said that such interventions are premature. “There is a rush to find the holy grail therapeutic; however, if we don’t understand why, then we are putting the cart before the horse,” he said.—JF