For millions of people, sinusitis can drag on for months or years, unresolved by medical interventions. The focus used to be on antibiotic treatments to purge infections that most experts believed were causing chronic sinusitis. Yet many patients relapsed, leading researchers and clinicians to question their assumptions.
In the last decade, a new insight has emerged. “People have taken a step back and looked at chronic sinusitis as being probably more of an inflammatory disease process,” more like asthma, said Dr. Bradley Marple, an otolaryngologist at the University of Texas Southwestern Medical Center in Dallas. “We may not be dealing with an infectious disease all the time,” he said, in which case antibiotics may not help much.
Clinicians have refocused treatment on attacking the underlying inflammation of chronic sinusitis, using anti-inflammatory measures like steroid drugs. And scientists are seeking to uncover what causes the inflammation in the first place.
Each year, millions of adults complain of sinusitis. Normally, the sinuses produce mucus and drain it through small openings into the nasal passages. But in rhinosinusitis, as the disorder is technically known, swelling in both the nose and sinuses blocks that drainage.
The result is a stuffed-up nose and an endless outpouring of green or yellow mucus. Pain or pressure builds up around the eyes or in the face, sometimes accompanied by headaches and toothaches.
For Cindy Martinez, a 43-year-old teacher in Santa Cruz, Calif., the pressure became so bad, “I just wanted to crack open my sinuses to get the stuff out, because it was pushing so hard on my face.” She battled repeated sinusitis attacks for six years.
Short-term episodes of sinusitis that last up to four weeks are caused by infections and, if bacteria are involved, can be remedied with antibiotics and steroids. But the story isn’t so simple with the stubborn symptoms of chronic sinusitis, which may afflict as many as 14 percent of Americans, according to self-reported data, though some experts say these numbers are inflated.
Until recently, scientists and doctors couldn’t even agree on what, exactly, chronic sinusitis is. It wasn’t until 2003 that several medical societies redefined the condition not as a single disease but as a group of disorders marked by sinus and nasal inflammation lasting at least 12 weeks. And the problem can arise from multiple causes.
Predisposing factors for persistent sinus trouble are numerous, ranging from a deviated septum and bad allergies to immunodeficiency. But the underlying disease process has long been an enigma. Over the years, experts bounced from one popular theory to another that promised to explain why sinuses become chronically sick.
Sinusitis is a bit of a “fad-based specialty,” Dr. James N. Palmer, director of rhinology at the University of Pennsylvania, said with a chuckle. “The fad at one point was, ‘It’s all bacterial infection.’ Then a fad was, ‘All you had to do is open up the sinuses’?” — with surgery — “and everything would drain out.” Another hot theory blamed an allergic reaction to fungi for a majority of chronic sinusitis cases.
None of those ideas proved to be the answer. A fungal allergy can be a culprit — but only in some cases. And while sinus surgery can bring significant relief by clearing out inflamed tissue and nasal polyps, which are a common source of sinus blockages, the polyps often grow back.
Different research groups are now pursuing other explanations for the abnormally heightened inflammatory response that occurs in chronic sinusitis. Some are exploring weaknesses in the innate immune defenses of the sinuses and nose. Others are teasing apart the role of bacteria, which can stimulate inflammation by their presence without necessarily causing infections.
Dr. Palmer and his colleagues are exploring the role of communities of bacteria called biofilms in the sinuses of chronic sinusitis patients. The investigators speculate that in some individuals, biofilms — particularly those containing the bacteria Pseudomonas aeruginosa or Staphylococcus aureus — can spur the immune system to mount an overexuberant inflammatory response that leads to sinusitis symptoms. Because the biofilm structure makes it hard for antibiotics to kill the bacteria, surgery to remove inflamed sinus tissue may ultimately be the best way to deal with the problem, Dr. Palmer said.
Dr. Palmer estimates that biofilms play a role in 25 to 30 percent of chronic sinusitis cases. But the theory remains unproved, and it is possible that biofilms are just innocent bystanders. Many patients with the ailment test negative for biofilms — and some healthy people test positive.
A different hypothesis, proposed by Dr. Claus Bachert, an ear, nose and throat doctor at University Hospital Ghent in Belgium, is that Staph aureus bacteria release a toxin or “superantigen” in chronic sinusitis sufferers with nasal polyps, unleashing a storm of inflammation. Such patients “really suffer much more than others,” he said. They often have recurring polyps and get severe asthma, perhaps through the same inflammatory process.
In unpublished trials, his team tested experimental inflammation-fighting drugs that target the immune proteins IgE or interleukin-5 in polyp patients, with encouraging results, Dr. Bachert said. In other research, he found that doxycycline, an antibiotic that also suppresses inflammation, provided longer-lasting benefits in shrinking nasal polyps than an oral steroid did.
Regardless of what may be causing chronic sinusitis, the treatment goal is controlling inflammation and helping the sinuses to drain.
The most effective first-line intervention, said Dr. Palmer, is nasal irrigation using a neti pot or saline irrigation bottle, which helps flush out mucus and any inflammatory bacteria or allergens in it. “If you took all the people who say they have chronic sinusitis in the world, and you put them all on nasal saline irrigations, a big proportion would not have any symptoms anymore,” he said.
Medicines for quelling inflammation include steroids, Dr. Marple said, and sinus surgery can sometimes be useful for removing obstructions to mucus clearance. Still, for many people, chronic sinusitis is “a disease that you’re not going to cure,” he said. The most you can hope for is “to manage it.”
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