Rhinitis

Rhinitis
Rhinitis is characterized by inflammation of the mucosal soft tissue with clinical symptoms of nasal discharge, blocked nose and itch-triggered sneeze occurring for more than one hour on most days. It is a common ailment (about 40% of the population) which may significantly interfere in the patient’s quality of life, by causing fatigue, headache and cognitive impairment. In general 85% of rhinitis sufferers have sleep disturbance, are physically limited, have reduced concentration at work and show significant changes to social life. In the majority the treatment of rhinitis requires effective management of coexisting or complicating respiratory conditions, such as asthma. Sinusitis and chronic otitis media are other complicating conditions.

Rhinitis may be caused by allergic or non-allergic factors but some individuals may suffer from both types. Allergic rhinitis is always associated with elevated levels of IgE antibody. Allergy is the major cause (80%) of rhinitis in childhood and the middle-aged sufferers but in older individuals about half are allergic rhinitis and the rest being non-allergic disorders. Risk factors for allergic rhinitis include: (1) family history of allergy, (2) serum IgE levels greater than 100 kU/L in adults and 10 to 100 kU/L in children, (3) high exposure to indoor allergens such as, dust mites, pet dander (cat, dog, hamster, rabbit), pollens, pest mammalian-epithelium (rats), insect pests (cockroach), mould spores, and (4) positive reaction noted clinically or by CAP RAST blood tests, to specific allergen in foods and aeroallergens. Allergic rhinitis tends to be persistent and chronic in Malaysia. The most important allergens associated with allergic rhinitis include house dust mites (85%), cockroach (66%), cat or dog dander (30%), pollens (e.g. oil palm, Acacia) (25%), mould spores (20%) and foods (22%). The foods most important in children are egg white, milk, shrimp and banana but in adults it may be shrimps and garlic.

Non-allergic rhinitis is characterized by sporadic or persistent perennial symptoms of rhinitis that do not involve IgE-mediated pathologic mechanisms. There are several causes for non-allergic rhinitis including infections (viral, bacterial, parasitic), structural/mechanical factors, eosinophilia syndrome, vasomotor rhinitis, drug induced, hormone induced, exercise induced, emotion factor induced, various diseases and other factors. In nasal eosinophilia large numbers of eosinophils cells are normally associated with nasal polyps, aspirin sensitivity and other non-steroidal anti-inflammatory drugs. Neutrophil cell infiltrates are generally present in virus and bacterial infections of the nose. Inflammatory cells, such as eosinophils and basophils, are absent in several types of non-allergic rhinitis. Hormonal changes due to thyroid disease or pregnancy or menstrual cycle or oral contraceptives can result in nasal congestion giving the impression of an allergy-like condition.