An allergy happens when our body’s immune system produces an exaggerated response to a normally harmless substance (allergen). An overwhelming response with antibodies results in powerful inflammatory chemicals released. The symptoms are itchy ears, nose and throat; sneezing, runny or blocked nose, headache; cough, sore throat and hoarseness; dark circles under the eyes and conjunctivitis. Long term, recurrent rhinosinusitis, large edematous inferior turbinates, middle ear infections, snoring and sleep apnea can result. For patients with crooked nose bone (deviated septum), an allergy of the nose can rapidly block the breathing when there is exposure to the allergen.
- Large inferior turbinate swelling next to the nose septum bone
- Cobblestone appearance of back of throat suggestive of allergy
Differentiating a cold, allergy and sinusitis. Fever is not needed for diagnosing a cold or sinus infection. Symptoms of cold continue throughout the day, and can last 1 to 2 weeks. A house dust mite allergy will cause symptoms in the morning and night, as the bedrooms with soft furnishings have a high burden of dust mite allergens, and we spend many hours there. Symptoms of sinusitis are more severe and can last for weeks to months.
- In sinusitis, air spaces (normally black in CT scan pictures) in the facial bones (sinuses) are filled with pus, polyps and inflamed mucosa.
Worldwide, allergies affect 35% of people. There is a genetic predisposition – 33% risk for a child with one allergic parent, and 70% risk if both parents have allergies. Over use of antimicrobial agents, processed foods and environmental pollutants have also been thought to increase the risk of allergies.
Haze from forest fires have dust, smoke particles, chemicals and gases. Haze exposure aggravates the allergic ENT symptoms. During a haze reaching an unhealthy PSI, I see a 25% increase in ENT allergy related problems. During Covid19 novel coronavirus times, when people stay at home a lot more, if they are allergic to allergens at home, they may also have more allergies of the ear, nose and throat.
- Skin Prick Test for children and adults can identify air-borne and food allergens
Diagnosis of ENT Allergy. Not all chronic runny and blocked nose are allergy related – 1 in 3 are non-allergic rhinitis. Allergies in ENT are usually air-borne (inhalant), but may also be food related. Testing for allergies is complex, especially for those with delayed allergy reactions and non-IgE food allergies, with differences in management philosophies common amongst doctors. Indiscriminate and over testing, without careful clinical correlation is unhelpful.
At our clinic, Skin Prick Tests (SPT) of diluted extracts from common local allergens (eg house dust mite, dog and cat dander, grass and tree pollen, cockroach, mold) is deposited onto the skin surface. Babies and adults alike manage this well, and results are known after 20 minutes. Prior to the test, our clinic will advise on a list of medications and food to avoid, so that the test is accurate. Some patients have severe skin eczema, or are unable to stop medications that interfere with the SPT; and our clinic will suggest a blood RAST test instead.
Treatment include avoiding and reducing the offending allergens. This can be challenging sometimes –eg tree and grass pollens in an outdoor lover, or pet dander floating from houses miles away and present even 4 months after removal of the animals. Face masks and medications are helpful. Medications usually used are nasal rinse, antihistamine, decongestant, corticosteroid and leukotriene inhibitor. Many patients confuse nasal steroid sprays with anabolic oral steroids. Nasal steroid sprays are not associated with the more significant side effects of oral steroids, and can be safely used from 2 years of age if appropriately dosed. Nowadays, sublingual or tablet immunotherapy taken orally are allowing many patients to control their allergies more effectively, and reduce the need for long term steroid sprays or antihistamine medications. Immunotherapy can be used from 4 years of age, and desensitizes the patient to the offending allergen, so that he/ she does not have start on the cascade of inflammation when encountering the allergen.
Challenges with food allergy. Ninety percent of reported food allergies come from a few foods – egg, milk, peanut, tree nut, shellfish, soy, wheat, and fish. Sometimes, ENT symptoms or abdominal discomfort may manifest hours or days after consumption, making identification difficult. Not all food antigens survive processing into standard extracts for skin tests. Selected blood tests may be needed, but the amount of antibody measured may not always reflect the severity of the allergy. Very careful history, diet charting, clinical examination over time, targeted testing and a trial of diet revision is required.
