Mar 21, 2012 (CIDRAP News) – More than 90% of sinus infections are caused by viruses and should not be treated with antibiotics, a common practice that can increase bacterial resistance to the drugs, the Infectious Diseases Society of America (IDSA) said in new guidelines released today.
Nearly one in seven people is diagnosed with a sinus infection each year, and such infections are the fifth leading reason for antibiotic prescriptions, the IDSA said in issuing its first formal guidelines on the topic. But 90% to 98% of cases are caused by viruses, which are not fazed by antibiotics, it said.
"There is no simple test that will easily and quickly determine whether a sinus infection is viral or bacterial, so many physicians prescribe antibiotics 'just in case,'" said Anthony W. Chow, MD, chair of the guidelines panel, in an IDSA news release.
"However, if the infection turns out to be viral—as most are—the antibiotics won't help and in fact can cause harm by increasing antibiotic resistance, exposing patients to drug side effects unnecessarily and adding cost," said Chow, who is a professor emeritus of infectious diseases at the University of British Columbia in Vancouver.
A sinus infection, called acute rhinosinusitis, is inflammation of the nasal and sinus passages that can cause uncomfortable pressure on either side of the nose and last for weeks, the IDSA statement noted. Most cases develop during or after a cold or other upper respiratory infection, but other factors such as allergens and environmental irritants may play a role.
In what the IDSA calls a major shift from older recommendations, the guidelines call for treating bacterial sinus infections with amoxicillin-clavulanate instead of the current standard of care, amoxicillin. "The addition of clavulanate helps to overcome antibiotic resistance by inhibiting an enzyme that breaks down the antibiotic," the statement said.
Also, Chow said this change was prompted in part by the common use of pneumococcal vaccines, which have changed the pattern of bacteria that cause sinus infections.
The guidelines also advise doctors not to use other commonly used antibiotics, including azithromycin, clarithromycin and trimethoprim-sulfamethoxazole, because of increasing drug resistance.
The 11-member panel that developed the guidelines used the GRADE system (Grading of Recommendations, Assessment, Development, and Evaluation), which is designed to more clearly assess the quality of evidence and strength of recommendations, the IDSA said. The guidelines note that randomized controlled trials referenced in previous guidelines often don't differentiate between bacterial and viral causes of infection and therefore may not provide the best recommendations.
"These are the first evidence-based rhinosinusitis guidelines using the GRADE system," Thomas M. File, Jr, MD, co-author of the guidelines, said in the statement. He noted that the guidelines clearly state the quality of evidence for each recommendation. File is chair of the Infectious Disease Section at Northeast Ohio Medical University, Rootstown, Ohio.
The guidelines say a sinus infection is likely to be bacterial and should be treated with antibiotics if symptoms last 10 days or more without improving or if they are severe or get worse.
Whereas most previous guidelines have recommended 10 to 14 days of antibiotic treatment for bacterial infections, the IDSA says 5 to 7 days is long enough to treat such infections without promoting resistance. But 10 to 14 days of treatment is still considered appropriate for children.
The IDSA also advises that:
- For both viral and bacterial sinus infections, decongestants and antihistamines are not helpful and may make symptoms worse. Nasal steroids can help ease symptoms in people who have sinus infections and a history of allergies.
- Nasal irrigation with a sterile solution—sprays, drops, or liquid—may help relieve some symptoms, but this may not be helpful in children because they are less likely to tolerate the discomfort of the treatment.
Very little information is available on the percentage of sinus infections that are treated with antibiotics, Chow told CIDRAP News via e-mail.
In one US national survey in 2006, 81% of adults with symptoms of sinusitis were prescribed an antibiotic, he said, adding, "My own conservative estimate is 50%-60%. However, given that only 2%-10% of patients presenting to a doctor's office likely have a bacterial infection, this is still very excessive."
Chow commented that antiviral therapy for upper respiratory infections "is in its infancy, and primarily directed at life-threatening infections such as influenza, meningitis, etc, and not for relatively self-limited infections such as the common cold." The current emphasis in treatment, he added, is on adequate rest, lots of fluids, and analgesics.
Chow AN, Benninger MS, Brook I, et al. IDSA clinical practice guidelines for acute bacterial rhinosinusitis in children and adults. Clin Infect Dis 2012 (online publication Mar 20) [Full text]