Perennial rhinitis

British Medical Journal, March 21, 1998 by I.S. Mackay, S.R. Durham

Perennial rhinitis may be defined clinically as an inflammatory condition of the nose characterised by nasal obstruction, sneezing, itching, or rhinorrhoea, occurring for an hour or more on most days throughout the year. In one study in London of adults between the ages of 16 and 65 years, the prevalence of rhinitis was 16%; of these, 8% had perennial symptoms, 6% perennial and seasonal symptoms, and 2% seasonal symptoms alone. As with asthma, both seasonal and perennial rhinitis seem to be increasing.

Classification

Allergic rhinitis--Perennial allergic rhinitis can be more difficult to diagnose than seasonal allergy, particularly if the patient presents with secondary symptoms of sinusitis and a "permanent cold." The most common allergen to account for perennial allergic symptoms is the house dust mite (Dermatophagoides pteronyssinus). Other frequent causes are animals: particularly cats, dogs, and horses.

Occupational rhinitis may result from allergy to airborne agents in the workplace--for example, laboratory animals and latex.

Infective rhinitis--Infective rhinitis may be acute or chronic. Chronic symptoms may be due to specific infections, such as fungi or tuberculosis. Chronic infection may also be the result of a host defence deficiency; this may be systemic (for example, panhypogammaglobulinaemia, IgA deficiency, or AIDS) or a local problem (for example, primary ciliary dyskinesia).

Other factors--Other non-allergic, non-infective factors may be involved (see box).

Differential diagnosis

Structural abnormalities of the nose include deviation of the nose or septum, enlarged middle and inferior turbinates, adenoidal hypertrophy (particularly in children; rare in adults), and choanal atresia The ostiomeatal complex is the area lying between the middle and inferior turbinates and the natural ostium of the maxillary sinus. It is this area which drains and aerates the maxillary sinus, the anterior ethmoidal sinuses, and the frontal sinus. Obstruction in this area, whether structural or secondary to an inflammatory condition, will predispose to sinusitis.

Nasal polyps result from inflammation of the mucosal lining of the sinuses; the lining prolapses down, particularly from the anterior ethmoidal sinuses through the middle meatus to obstruct the nasal airway. Allergy does not seem to be an important factor. Nasal polyps in children are rare and are almost invariably associated with cystic fibrosis. A strong association exists between nasal polyps, asthma, and sensitivity to aspirin (Samter's triad).

Granulomatous rhinitis may be associated with Wegener's granulomatosis and sarcoidosis.

Primary atopic rhinitis is characterised by nasal congestion, hyposmia, and an unpleasant smell (ozoena), resulting from a progressive atrophy of the nasal mucosa and underlying bone. Secondary atrophic rhinitis may result from radical surgery, infections, irradiation, and trauma.

Leaking of cerebrospinal fluid will present with watery rhinorrhoea, often unilateral. It is usually associated with trauma (including surgical trauma) or neoplasia, but spontaneous leaking may occur.

History and examination

Taking a history need not be time consuming A glance at the classification and differential diagnosis will suggest the most important questions.

Rare, sinister causes for rhinitis need to be excluded. Unilateral symptoms should always be regarded with suspicion, particularly if associated with symptoms of increasing nasal obstruction, blood stained nasal discharge, or facial pain.

Ear, nose, and throat surgeons examine the nose with a head mirror or headlight and a nasal speculum, but increasingly this is supplemented by rigid or flexible nasendoscopy. In general practice, the nose can be examined with an auriscope fitted with the largest speculum. It is easy to confuse a large, swollen, oedematous inferior or middle turbinate with a polyp; polyps, however, unlike turbinates, are usually pale grey, translucent, and mobile and lack any sensation on gentle probing.

Investigation

Perennial allergic and non-allergic rhinitis may require no specific investigations other than skin prick testing, which has been fully discussed in an earlier article in this series. If the history or examination suggests that other factors need to be excluded, the patient may require a variety of investigations, depending on the history and clinical findings.

Special tests

In addition to routine full blood count and eosinophil count, immunoglobulin concentrations should be checked. Blood tests for antineutrophil cytoplasmic antibody and angiotensin converting enzyme may be indicated if, respectively, Wegener's granuloma or nasal sarcoidosis is suspected. It is also important to consider whether the patient may have AIDS or be compromised by treatment with immunosupressant drugs. When skin prick tests are not available or not possible for other reasons, blood allergen specific IgE concentrations may be determined (with the radioallergosorbent test).

Imaging

Plain x ray films of the sinuses can be misleading. Computed tomography of the sinuses in the coronal plane has become the standard international imaging method.