Study:
Chronic Sinusitis is an Immune Disorder
Researchers
at the University at Buffalo and the Mayo Clinic have
shown that chronic sinusitis is an immune disorder caused
by fungus, opening up a promising new avenue for treating
this ubiquitous and debilitating condition, for which
there is no FDA-approved therapy.
Results
of their research suggest that common airborne fungi
lodge in the mucus lining of the sinuses in most people,
but initiate an immune response only in individuals prone
to chronic sinusitis. The immune response causes the
fungi to be attacked, which leads to damage of the sinus
membranes, resulting in full-blown symptoms.
" We
hope this study will lead to the first treatment aimed
at the root cause of chronic sinusitis, rather than a
treatment just to mask the symptoms," said David
A. Sherris, M.D., interim chair of the UB Department
of Otolaryngology.
Sherris
presented the study findings on March 23, 2004, at the
annual meeting of the American Academy of Allergy, Asthma
and Immunology in San Francisco. The research was conducted
while Sherris was at the Mayo Clinic.
Through
a randomized, placebo-controlled, double-blind pilot
trial using the fungicide Amphotericin-B applied intranasally,
the researchers found that the treatment group showed
a significant decrease in the inflammatory thickening
of the sinus membranes compared to the control group.
Inflammation
in the mucus also decreased significantly in those receiving
the drug, compared to placebo, and 70 percent of patients
on the medication had a decrease in the amount of nasal
swelling, results showed.
" We
showed in 1999 that fungal organisms were present in
the mucus of 96 percent of patients who had surgery for
chronic sinusitis, and that inflammatory cells were clumped
around the fungi, which indicated to us that the condition
was an immune disorder caused by fungus," said Sherris. "But
many doctors didn't believe us."
" Next,
we conducted various immunologic studies and an open
trial using the fungicide treatment and found that 75
percent of patients improved on the new therapy. Now
we have similar results from a randomized, blinded trial
with a control group, which is the 'gold standard' in
drug testing. Our next step is to conduct a multi-center
trial using antifungals, which we hope will lead to FDA
approval of antifungal treatment for this chronic disease."
Chronic
sinusitis, a disease of the nasal passages and the surrounding
sinus cavities, is thought to affect 16.8 percent of
the adult population of the U.S. It causes long-term
nasal congestion, production of thick mucus, loss of
sense of smell and creates an environment for opportunistic
bacterial infections that exacerbate those symptoms.
Sherris said studies have shown that chronic sinusitis
exceeds even congestive heart failure in its adverse
effects on quality of life.
Little
is known about the causes of sinusitis. Without a specific
target for intervention, physicians often simply treated
the secondary bacterial infections in hopes of providing
a modicum of relief.
The
current trial involved 24 patients with chronic sinusitis
who were randomly assigned to receive the treatment or
a placebo. Neither the patients nor the investigators
knew who received the drug or the inactive agent. The
final analysis involved data from 10 treatment patients
and 14 controls, all of whom were in the trial for six
months.
Researchers
took CT scans (special x-rays of the sinuses) at baseline
and at 6 months. They also graded patients' inflammation
by direct exam with an endoscope in the nose at the start
of the study, and at 3 and 6 months.
The
CT scans showed that the treatment group had a mean 8.8
percent decrease in inflammatory mucus thickening, while
the placebo group had an increase of 2.5 percent. Sherris
said 70 percent of patients in the treatment group also
showed significant improvement when their nasal passages
were viewed through an endoscope, while the placebo group
showed no change. Markers of inflammation in the mucus
also decreased significantly in the treatment group,
compared to the placebo group.
Additional
researchers on the study, all from the Mayo Clinic, were
Jens U. Ponikau, M.D., Amy Weaver, Evangelo Frigas, M.D.,
and Hirohito Kita, M.D.
The
research was supported by grants from the National Institutes
of Health and the Mayo Foundation for Education and Research.
The
above article first appeared in the May 1, 2004 edition
of Sinus News.
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