Allergy and Sinus

What is sinusitis?
 Sinusitis is defined as inflammation of the sinus cavities. Sinuses are the hollow cavities within the bones of the face. They are lined by mucous membranes that normally produce mucous/fluid. This fluid drains into the nose and is swallowed throughout the day (under normal circumstances, you should not be aware of this fluid).When the drainage of the sinuses are blocked, an infection can develop.
 What is the difference between rhinitis and sinusitis?
 Just as sinusitis is the inflammation of the sinus cavities, rhinitis is the inflammation of the nasal passages. They almost always go hand in hand, but severity of either is variable.
 What causes this inflammation?
 This is a very good question and is the underlying cause of both rhinitis and sinusitis.Anything that irritates the lining incites the inflammatory pathways.All the following result in similar symptoms:
·         Allergy – inhaled or otherwise
·         Infection – Viral, bacterial and fungal. Infections can be caused by viruses such as the common cold or influenza. These are the most common causes. Bacterial infections are the types of infections that respond to antibiotics. Less commonly however, sinus infections are caused by fungus or moulds.
·         Pollution including cigarette smoke
·         Temperature change or humidity change
The cause of the inflammation will determine the best management. However, most often the symptoms are a sum total of all factors, so to unravel the cause is not always straight forward. Severe or long standing inflammation blocks the sinuses and predisposes to infection – see above)
 What are the symptoms of rhinitis?
 Can roughly be divided into irritative (runny nose, sneezing) or congestive (post nasal drip, blocked nose) symptoms.
 What are the Symptoms of Sinusitis?
 These symptoms are more intense compared to rhinitis and include
·         Facial pain and pressure over the involved sinus(es)
·         Nasal congestion
·         discoloured nasal discharge
·         Decrease in smell and taste sensations
·         Fever
·         Headache
·         Bad breath
·         Fatigue
·         Cough
·         Teeth pain
·         Ear pressure or pain
·         Post nasal drip
Symptoms above tend to be more often associated with acute sinusitis (subacute and chronic sinusitis have less severe symptoms)
 How are sinus infections differentiated?
 Most of the time, sinus infections are differentiated on how long the infection has been going on:
Acute sinusitis: Infection (any cause) is present for less than four weeks. Symptoms include facial pain or pressure over the involved sinus, discoloured nasal discharge (green, yellow, milky or gray), nasal congestion, headache, fever, post-nasal drip and cough.
Chronic sinusitis: Infection present for eight weeks or more. Symptoms consist of nasal congestion, post-nasal drip, milder headaches, chronic cough and fatigue.
Recurrent sinusitis: Defined as three or more sinus infections per year. These may be due to an incompletely treated chronic sinus infection, or new infections.
 What is the role of allergies?
 Allergies predispose a person to developing sinus infections, as they cause inflammation and thus sinus blockage.
 How is allergy evaluated?
 Allergy is evaluated according to the suspected allergen.
·         Food allergy, although they can be evaluated by blood tests, is best done by elimination-challenge diets. This helps for the reactions not covered by the blood tests (non IgE mediated reactions)
·         Inhaled allergens are best tested by either skin prick tests or RAST blood tests. Both have advantages and disadvantages. The RAST is more accurate, but also more expensive. The skin prick tests are very cost effective, but are interfered with by medicines that allergy sufferers are commonly on. Common inhaled allergens are house dust mite, grass pollens, tree pollens, moulds, animal dander, weed pollens, feathers. These are usually geographically dependant.
Even if done correctly, a negative allergy test does not exclude an allergy, but excludes an allergy to that particular allergen.
Keep an allergy diary.
 What else can cause or predispose to sinus infections?
 Other factors include:

  • Anatomical or structural abnormalities within the nasal passages and sinuses, such as a deviated septum (divides the nasal passage into two sides) and other bony abnormalities that may prevent the sinuses from draining.
  • Problems with low immune function eg. as a result of a genetic problem (such as cystic fibrosis), as a result of infection (such as HIV/AIDS), as well as other diseases that affect antibody levels (such as multiple myeloma).
  • Gastroesophageal reflux disease (GERD)
  • Non-allergic rhinitis or vasomotor rhinitis.
  • Age and pregnancy
  • Underlying thyroid or other metabolic or medical conditions.
 How are the anatomical abnormalities found?
 These abnormalities are usually picked up with a good clinical examination including a flexible nasendorhinoscopic procedure performed by an ENT specialist and confirmed on CT scan.
 How are these abnormalities treated?
 These abnormalities are most effectively treated with surgery, such as septoplasty. Because the underlying problem is primarily an inflammatory condition, this must be treated first and surgery reserved for anatomical abnormalities not responsive to treatment or if complications have occurred. 
 How are Sinus Infections Diagnosed?
 A sinus infection is suspected in a person with the above symptoms and consistent findings on examination. A CT scan is usually done if anatomical problems or complications suspected (x-rays of the sinuses are NOT necessary). Imaging studies are very helpful in people with chronic or recurrent infections – and this almost always is a CT scan and NOT a plain x-ray.
 How are Sinus Infections Treated?
 The main treatment for sinus infections is antibiotics. While acute sinus infections usually respond to antibiotics alone, chronic sinus infections are often caused, at least in part, by inflammation in the nasal passages and sinuses. Therefore, other medications are needed to reduce this inflammation so that the infection can drain from the sinuses. Nasal (and sometimes oral) steroids, mucolytics and decongestants are used.
 What general measures can I take?
 I strongly recommend regular saline irrigation and steaming with certain volatile oils, eg. menthol, eucalyptus. Remember, the “fitness” of your sinus mucosa is determined by your overall fitness. In other words the speed at which the lining of your nose returns to normal after being irritated is also influenced by your cardiovascular fitness level. Excercise and eat well and it will improve your sinus health.

Ear,Nose and Throat Specialists