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What is rhinosinusitis and how do we get it?
Rhinosinusitis is an inflammation of the lining of the nasal passages and paranasal sinuses. It is not always
believed associated with or caused by bacteria. There are several forms of rhinosinusitis. These include: acute,
subacute, chronic, recurrent acute and acute exacerbation of chronic. Chronic rhinosinusitis may be seen with
or without nasal polyposis.
Nasal Polyps are benign tumors of the upper airway which are often time associated with many eosinophils (a
type of white blood cell). They are not believed to have any malignant potential. There are many conditions
which are associated with their formation and unfortunately in a given person, it may be impossible to
determine what the cause of the polyps is. Most often nasal polyps tend to recur. The speed with which they
recur is often associated with failure to comply with ongoing medical therapy. Steroids are often very effective
in reducing their size temporarily particularly if eosinophils (a certain type of white blood cell) are associated
with their formation. Rarely aggressive sinus tumors or malignancy can appear within polyps.
Swelling around the small openings to the sinuses caused by environmental irritants, viruses, allergy, or other
conditions can result in rhinosinusitis. The mucus in the nose and sinuses can secondarily become infected by
bacteria or fungi. It is suggested that forceful nose blowing can lead to contamination of the sinuses with
organisms and therefore is best minimized. When the blockage occurs, swelling of the sinus lining can disable
the cilia and the drainage of the mucus blanket.
Most episodes of rhinosinusitis are believed initiated with viral upper respiratory tract infections (eg the
common cold or flu) (see information sheet on Viral Upper Respiratory Tract Infection). Those with a genetic
predisposition towards allergy, immune dysfunction, aspirin sensitivity, and chronic rhinosinusitis seem to be
most susceptible to the long term effect of viral infections.
Environmental pollutants in the air, such as cigarette smoke, can cause increased irritation of the nasal and sinus
passages, particularly in people with hypersensitive nasal lining (mucosa). We are also becoming more aware
of the effects of both general outdoor and indoor pollution. Chemicals used in the manufacturing of carpets,
furniture, or buildings may also be a problem for sensitive individuals.
If you have allergies, your nose may react to allergy-inducing substances in the air, such as dust or mold.
Allergic nasal and sinus swelling may in turn lead to sinusitis. Food allergies (or sensitivities) can also be an
unrecognized cause of nasal congestion and swelling. Lastly, certain conditions that exist within your own
body can increase your susceptibility to sinus infections. For example, periods of emotional stress can result in
swelling of the nasal lining. Certain medications used to treat high blood pressure can also do this. Or, if you
have diabetes, high blood sugar can make you more prone to infections in general. Be sure to inform your
physician if you have, or suspect, any medical problems.
It is possible that Gastroesophageal Reflux Disease (GERD) may cause symptoms of rhinosinusitis, including
chronic cough and post-nasal drainage, but this hypothesis is not fully proven. This may be due to irritation
caused by excess acid from your stomach splashing up into your throat. If you have symptoms resembling
GERD, such as frequent acid indigestion/heartburn or a tightness sensation in your throat upon swallowing, you
will be given further information and instructions.
Lastly inherited conditions such as cystic fibrosis, immunodeficiencies, and ciliary abnormalities can be present
SNI Copyright 2004; Ver 3.14.2011 and surprisingly might be first detected later in life because of their unusual presentation.
Ongoing Research to Improve our Understanding of Chronic Rhinosinusitis
A variety of centers throughout the world are engaged in laboratory and clinical research to better improve our
understanding of this disorder. There is growing evidence to suggest certain bacteria and or molds may play a
substantial role in sustaining chronic rhinosinusitis. Currently, these ideas are getting a lot of attention but they
are not yet well understood. The organisms attracting the most attention are bacteria called Staphylococcus
aureus and Pseudomonas aeruginosa and fungi called Alterneria and Candida (molds and yeast). The three
leading ideas describing possible reasons for chronic rhinosinusitis are referred to as the:
1. Super-antigen driven rhinosinusitis
2. Fungus induced rhinosinusitis
3. Biolfilm related rhinosinusitis
Super-antigen Driven rhinosinusitis
It has been demonstrated that certain toxins produced by Staph. called “super-antigens” can stimulate and “short
circuit” our immune response. Other organisms are know to produce toxins but whether or not they can
stimulate the immune system the same way is not well studied. The end result is that certain white blood cells
called eosinophils are produced in abnormal quantities and sent from the bone marrow to the sinuses where they
release toxic substances. Eosinophils sustain the inflammation seen in chronic rhinosinusitis with or without
Fungus Induced Rhinosinusitis
Interestingly, unlike other white blood cells, eosinophils seem to have a primary function of killing macro
organisms such as worms and fungi. Thus, fungi also attract eosinophils and appear to play an important role
in chronic rhinosinusitis. Non-invasive fungal rhinosinusitis affects multiple sinuses in young adults.
Treatment may include anti-fungal medication, oral steroids, intranasal steroids, oral decongestants, mucolytics
and immunotherapy. Functional endoscopic sinus surgery is also a treatment for the management of fungal
sinusitis. If there is suspicion of a fungal infection or if your cultures are positive for fungus, you will be treated
Biofilm Related Rhinosinusitis
Staph. species, Pseudomonas and Candida are also known to form protective covering over themselves in a
“biofilm” which can tightly adhere to surfaces. Whether or not these are actually present in chronic
rhinosinusitis is difficult to prove and laboratory research is currently underway. In this biofilm, under the
protection of the “glycocalyx”, these organisms can co-exits and share resistance mechanisms to antimicrobial
agents. Thus antimicrobials alone have reduced effectiveness when these biofilm are present. This hypothesis
ties together the aforementioned ideas and may help explain why some patient improve so much after long
course of antibiotics only to relapse shortly after discontinuing the medicines.
Successful Treatment of Chronic Rhinosinusitis Often Depends Upon Continuous Treatment
Chronic rhinosinusitis is a chronic condition for which we do not typically have a cure. We do have many
SNI Copyright 2004; Ver 3.14.2011 treatments that can improve quality of life and that can minimize your need for systemic antibiotics and
steroids. Getting this problem under control can take more than a year once it is well established.
Therefore, continuous medical therapy is required to control chronic sinus inflammation and to prevent the
sudden disabling exacerbations of your condition. Stopping treatments without consulting with your physician
is likely to lead to worsening of the condition. Especially when polyps are involved in chronic rhinosinusitis,
patients can be particularly unreliable in gauging their own problem. This is because polyps are less sensitive
tissue than the normal sinus lining. Thus it is not until there is a reappearance of nasal blockage, cough, asthma,
colored nasal drainage, or loss of sense of smell when the problems are noticed.
Nasal endoscopy (an office based procedure) can help detect the problem before it gets out of hand. The nasal
endoscope is a diagnostic tool that helps your healthcare professional detect your ongoing problem despite your
symptom improvement. Practically speaking this helps in diagnosis much like a blood pressure cuff detects high
blood pressure before a stroke or heart attack occurs. This is why some treatments will be advised continually
based upon findings seen on your nasal examination even though you may feel much better after initial
treatments. Again, stopping treatments because you temporarily feel well is likely to cause a vicious cycle
apparently failed treatments. You should always tell your doctor about unusual or new symptoms that first
appear after starting treatments or if you suffer any side effects. Also some recommended treatment can
be very expensive and may not be possible for some patients. Regardless of the reason you would like to stop a
medication/treatment there might be alternative ideas on how to control your sinus inflammation and it should
be discussed with your doctor or healthcare professional.