Chronic rhinitis is a common condition affecting up to 40% of the population.
Allergic rhinitis (AR) is classified as an IgE mediated type 1 hypersensitivity. The classic symptoms of repetitive sneezing, anterior rhinorrhoea, nasal itch and ocular symptoms occur when the immune system overreacts to airborne allergens. Common allergens include house dust mite, animal dander, and moulds (perennial) and pollens from grasses, trees and weeds (seasonal).
AR symptoms will most commonly present before the age of 20. Often underdiagnosed and undertreated, it can significantly affect the quality of life of the person experiencing the symptoms, and is associated with absenteeism, presenteeism, and social withdrawal, mental health issues, fatigue and sleep disturbances. In younger children, behaviour problems can also occur.
Non-allergic rhinitis (NAR) is a diagnosis of exclusion. Generally accepted to have a female predominance and a later age of onset (third decade), it is the name given to the presence of one or more of the following symptoms: sneeze, postnasal drip, nasal congestion, rhinorrhoea and, to a lesser extent, nasal itch for greater than 12 months.
There is a distinct absence of specific aetiology (negative skin prick test, infection) but, in certain phenotypes of NAR, triggers can be identified and occasionally removed. This group includes, occupational (chemicals), pharmacological (nasal decongestant overuse and certain prescription medications) and hormonal (pregnancy).
When no cause can be identified it is often called idiopathic. NAR has also been referred to as hypersensitive nose, non-allergic non-infectious rhinitis (NANIR) or vasomotor rhinitis.
There is no unifying pathogenesis, but NAR is broadly divided into inflammatory and noninflammatory, which can be distinguished by inflammatory cells present or not in a nasal biopsy or in nasal secretions, namely the eosinophil.
One theory describes the symptoms of noninflammatory NAR arising from an abnormality in the autonomic nervous system, but the pathogenesis of this abnormality is unclear.
Gustatory rhinitis, the development of profuse watery discharge after eating hot or spicy foods, is a subtype of noninflammatory NAR.
Those who experience NAR regularly complain of clinical features of rhinitis due to hypersensitivity to odours and environmental changes. These triggers are frequently associated with the inflammatory subgroup. Odours include perfumes, scented candles, deodorant, aerosols, cosmetics, fragrant flowers, cigarette smoke, cleaning products, pine, wood or coal burning, mildew and paint fumes. Environmental causes include air conditioning, change of seasons, wind changes, barometric changes and temperature changes.
It is important to realise that AR and NAR can, and often do, coexist. When this is elicited from the history it is called a mixed rhinitis.
Diagnosing either AR or NAR relies on a precise medical history. Often too much emphasis is put on skin prick testing or serum specific IgE blood testing when an accurate diagnosis can be made from the patient’s history. A detailed history about triggers and symptom severity can help identify the offending agents. For instance, people often incorrectly believe pollen is the causative agent when walking outdoors on a windy day. While pollen can provoke rhinitis symptoms, so can a cool dry wind. Only the former is an allergy-mediated reaction.
Other features that help distinguish between NAR and AR can also aid in diagnosis. Aside from younger age of onset, those with AR may also have a history of eczema, food allergy and early onset asthma.
Family history is also an important feature of allergic disease. Repetitive sneezing, anterior rhinorrhoea, nocturnal blockage and itch are prominent features of AR. In contrast, the most prominent manifestations of NAR are constant nasal blockage and postnasal drip. Patients with AR can often readily identify a trigger, such as cats, dust or seasonal changes.
Those with NAR often struggle to identify their triggers, not aware of how many common household items can elicit a reaction.
It is important to stress again that a person may have features of both (mixed rhinitis). This is common in a person who is older (35 or more years of age) at presentation.
Asthma coexists with both AR and NAR in about 40% to 60% of patients, however people whose asthma develops later in life (adult-onset asthma) are less likely to be the allergic phenotype. Patients with the inflammatory phenotype of NAR appear to be at higher risk of development of asthma than the non-inflammatory.
It is of great value to perform an anterior rhinoscopy to assess for significant nasal structural abnormalities, polyp formation and foreign bodies, and to assess the inferior nasal turbinates. Nasal turbinates can be enlarged in both AR and NAR.
In allergic patients, the turbinates often appear pale and oedematous. Other classic symptoms of allergic disease can also be of value and should be explored. Allergic shiners (a sign of vascular congestion) and an anterior nasal crease are often seen in children with AR.
Clinically significant signs of mouth breathing are not to be missed.
Habitual snoring, high arched palate, teeth crowding, teeth malalignment and poor mandibular development are all manifestation of sleep disordered breathing in a child and referral should be considered.
Although a diagnosis of exclusion, it is not necessary to preform allergy tests to make a presumptive diagnosis of NAR. This is important to consider as the presence of a serum specific IgE to an allergen might not be the driving mechanism behind the patient’s presenting symptoms as in the case of mixed rhinitis.
Starting a trial of therapy, in either AR or NAR, is a reasonable first step even prior to a definitive diagnosis. This will allow time for the now informed patient to identify a trigger or triggers.
Topical intranasal corticosteroids (INCS) are the first-line therapy for both NAR and AR.
A good response to the anti-inflammatory effect of INCS is expected for both AR and the inflammatory subgroup of NAR. They are safe to use regularly and long term in the same way an asthmatic may need to use an inhaled corticosteroid long term.
Meta-analyses have shown INCS to be superior to oral antihistamines, topical antihistamines and mast cell stabilisers. Unlike other treatments, INCS may also reduce nasal blockage. The third generation INCS, such as mometasone furoate, fluticasone furoate, and fluticasone propionate are favoured for their low bioavailability and thus are a better choice in children.
More recently the combination INCS and topical antihistamine sprays have become a first-line consideration in patients over the age of 12 with moderate to severe symptoms.
Two formulations are available in Australia, fluticasone propionate and azelastine, as well as mometasone furoate and olopatadine. Both combination sprays have demonstrated superior clinical improvement in patients with allergic symptoms of the nose and eyes over using either agent alone. Although it has not been investigated, they are reported to have good efficacy in those with inflammatory NAR.
A significant issue with prescribing either combination spray is the cost and so adherence may be affected if this is not discussed at the time of prescribing.
A certain subset of patients with NAR will not respond to anti-inflammatory treatment with topical steroids.
There is reasonable evidence that capsaicin, the active component of chili peppers, is effective in alleviating symptoms including nasal blockage in those with NAR. The delivery of topical capsaicin produces a burning sensation which stimulates the target receptors in the nasal passages. The proposed theory is beyond the scope of this article, but it has been shown to be safe and effective in small clinical trials. Further investigation is ongoing.
Capsaicin nasal preparations are available online in Australia. No prescription is required. It should be considered in those who fail adequate response to topical steroid.
Other considerations for treatment can be considered based on specific symptoms.
Rhinitis in the older person (more than 65 years), once referred to as senile rhinitis, mainly manifests with a profuse watery discharge and absence of any other features. In this instance ipratropium bromide nasal spray may be all that is required. This can also be effective in those with pure gustatory rhinitis from spicy or hot foods.
Nasal saline can be a good adjunct to any therapy if administered prior to the medicated nasal spray.
Allergen-specific immunotherapy should be considered in those who have moderate to severe allergic rhinitis. In this case consider referral for skin prick test and review by an allergy specialist. Allergen-specific immunotherapy remains the only disease-modifying agent for allergic rhinitis.
Other conditions should be considered when evaluating a patient with suspected rhinitis.
Unilateral nasal discharge is not common in rhinitis and a red flag. Clear runny unilateral discharge could indicate a cerebral spinal fluid leak, and purulent unilateral discharge could indicate a foreign body, especially in a child.
Chronic rhinosinusitis, with or without nasal polyps, should also be considered in those complaining of chronic loss of smell and taste and facial pain and pressure.
Dr Jessica Tattersall is a clinical allergist based in Darlinghurst, Sydney. She has a specific interest in allergic and non-allergic disorders of the airways.
- Gevorgyan A, Segboer C, Gorissen R, et al., Capsaicin for non-allergic rhinitis. Cochrane Database of Systematic Reviews 2015(7).
- Scadding GK, Kariyawasam HH, et al. BSACI guideline for the diagnosis and management of allergic and non-allergic rhinitis (Revised Edition 2017; First edition 2007). Clin Exp Allergy 2017 -07;47(7):856.
- Hellings PW, Klimek L, Cingi C, et al. Non-allergic rhinitis: Position paper of the European Academy of Allergy and Clinical Immunology. Allergy (Copenhagen) 2017;72(11):1657-1665.
- Brozek, Jan L., Bousquet, Jean, Agache, Ioana, et al., Allergic Rhinitis and its Impact on Asthma (ARIA) Guidelines – 2016 Revision. Journal of Allergy and Clinical Immunology, The 2017;140(4):950-958.