Symptoms cannot reliably identify which patients with acute rhinosinusitis - infection of the nasal and sinus cavities, will benefit from antibiotic therapy, according to the results of a large review of previous studies. The investigators also found that about 15 symptomatic patients would need to be treated to cure one additional patient.

Based on their findings, Dr. Jim Young of the University Hospital Basel in Switzerland and colleagues conclude that antibiotic therapy should not be used to treat acute this common infection in adults, even if the symptoms have lasted for up to 10 days.

The overuse of antibiotics for acute rhinosinusitis is common because doctors are often unable to determine if the cause is viral or bacterial, the researchers explain. While bacterial infections will respond to antibiotic treatment, viral infections will not.

Therefore, treating viral infections with antibiotics contributes to the overuse of these drugs which, in turn, increases the risk of drug resistance.

The goal of Young’s review was to identify any common signs or symptoms in patients that might suggest one cause over the other.

As reported in the March 15th issue of The Lancet, Young and colleagues analyzed data from 2547 adults enrolled in nine trials identified through a search of Medline, Embase, and other sources.

The overall number of patients that would need to be treated to cure one patient was 15. If purulent discharge in the throat was present, which typically increased the duration of treatment needed, the number needed to treat declined to 8.

Older age, longer symptom duration, and more severe symptoms all predicted a longer treatment course, and was also linked to a greater benefit of antibiotic therapy.

“Although our results do not apply to children or to patients with a suppressed immune system, they should reassure physicians that only “watchful waiting” and symptomatic relief are warranted for almost all adult patients with acute rhinosinusitis-like complaints.”

The researchers “have shown that if any subgroups of patients with mild sinusitis respond substantially to antibiotic treatment, these subgroups are not easy to identify,” Dr. Morten Lindbaek, from the University of Oslo in Norway, and Dr. Christopher C. Butler, from Cardiff University in the UK, comment in a related editorial.

SOUCRCE: The Lancet, March 15, 2008.