A US study suggests that from 2001 to 2006 there has been a marked increase in the proportion of acute and chronic sinusitis cases in which the potentially deadly superbug MRSA has been isolated.
Sinusitis often begins when a cold, which is caused by a virus, leads to inflammation in the lining of the sinuses. Sometimes, this leads to a bacterial infection.
As the name implies, MRSA, or methicillin-resistant Staphylococcus aureus, is a bacterium that is resistant to the antibiotic methicillin. However, it is also highly resistant to several other drugs, including penicillin and amoxicillin, which can make it difficult to treat.
"An increase in the recovery of MRSA was recently noted in various infectious sites, including acute and chronic sinusitis in studies that were done in Taiwan," Dr. Itzhak Brook, who led the US study, told Reuters Health.
"However, no report of this increase was generated from any other country, including the US. Ours is the first study that actually shows an increase in recent years (2004-2006) as compared to previous ones (2001-2003)," Brook said.
In the study, the researchers analyzed cultures from 458 patients with acute or chronic sinusitis. Of these patients, 215 were seen from 2001 and 2003 and 243 were seen from 2004 to 2006.
For acute sinusitis, the percentage of patients with MRSA rose from 30 percent to 69 percent between the two periods - a significant increase. Likewise, for chronic sinusitis, the percentage increased from 27 percent to 61 percent.
Overall, 122 of the 214 patient with chronic sinusitis had been treated with an antibiotic in the previous 3 months. The rate of MRSA isolation in these patients was 23 percent compared with a rate of just 11 percent in their peers not treated with an antibiotic.
"It is important to remind the public and clinicians that over 98 percent of acute sinusitis is viral and resolves without antibiotics. Reducing the overall use of antibiotics for colds and non-bacterial sinusitis will reduce the emergence of MRSA sinus infection," Brook emphasized.
Brook, who is with Georgetown University School of Medicine in Washington, DC, presented the study findings this week at a gathering of infectious disease experts in Washington, DC.