Nasal lavage could be an integral component of assessing airway inflammation. Research into the reproducibility of cell counts is key to understanding the value of lavage results.

The objective of this study is to evaluate and compare the reproducibility of a common nasal lavage technique and its variation in a sample of subjects with nasal symptoms (e.g. runny nose, congestion, sneezing, post nasal drip), and in individuals without nasal symptoms.

Nasal lavage is a relatively simple way to measure the degree of upper airway inflammation. It is useful in research because it is noninvasive, relatively discomfort-free, and simple to perform. Yet there is no standardized method for collecting upper airway cells. The definition of nasal lavage can differ widely between research groups. The method, and its pooled modification, chosen for this trial are based on the commonly used Naclerio technique.

Upper airway inflammation is linked to a broad spectrum of disease: nasal polyposis, seasonal and perennial allergic rhinitis, vasomotor or non-allergic rhinitis, and sinusitis. Assessing the degree of upper airway inflammation through objective measures has obvious clinical and research benefits. For example, nasal polyps contain a large number of activated eosinophils - about 20% of the constituents of nasal polyp tissue. Allergic rhinitis is also associated with elevated inflammatory cell counts - eosinophils, basophils, mast cells, lymphocytes and their mediators. The impact of treatment on nasal inflammation is a key factor in the evaluation of new nasal polyp or allergic rhinitis therapies. Therefore it is imperative that nasal inflammation measurements be evaluated for reliability.

As nasal inflammation is present in a variety of diseases, a cross section of subjects will be enrolled in this trial. Nasal lavages will be performed on nasal polyp subjects, perennial allergic rhinitis subjects, and normal subjects. This project will assess the repeatability of a single sample lavage in comparison to the repeatability of a modified version, i.e. a lavage sample conducted three times, 15 minutes apart, and then pooled, or combined. We expect to find the highest eosinophil counts in patients with nasal polyposis, intermediate levels in patients with perennial allergic rhinitis and low levels in normal subjects, based on previous work.

This project will be a single-centre, randomized trial involving three sets of seven subjects - polyp subjects, perennial allergic rhinitis subjects, and normals. All subjects will be blinded to the assessment of outcome measurements.

The study will be comprised of four clinic appointments. Appointments will be scheduled seven to 10 days apart. All subjects will be randomly assigned their lavage sampling group at their baseline visit. Group one will consist of a single sample lavage at visit one, a multiple sample lavage at visit two, a single sample lavage at visit three, and a multiple sample lavage a visit four. Group two will be the reverse order.

Inclusion Criteria:

• Subject is male or female aged 18 years or older.
• Subject understands the research project and agrees to participate by signing an informed consent agreement.
• Subject is able to successfully complete nasal lavage training session.

Exclusion Criteria:

• Subjects with severe nasal polyps which prevent collecting adequate nasal lavage sample.
• Subjects who have undergone surgery to treat their nasal polyps (nasal polypectomy) within one year prior to visit one
• Subjects who have a known fungal infection of the nose and/or paranasal sinuses, nasal candidiasis, acute or chronic infectious sinusitis of viral or bacterial nature.
• Subjects who have had an upper respiratory tract infection within four weeks prior to visit one.
• Subjects having cystic fibrosis, Young's syndrome, primary ciliary dyskinesia, known HIV infection or alcohol abuse.
• Subjects with clinically significant, uncontrolled evidence of cardiovascular, neurological, hepatic, renal, respiratory, or any other medical condition that may interfere with the study.
• Subjects with a recent history (within six months) of a clinically significant psychiatric disorder other than mild depression.
• Subjects who have any clinically relevant deviation from normal in the general physical examination.
• Subjects who have received any depot, systemic or oral corticosteroid in the previous three months prior to the start of the study.
• Subjects who are using an intranasal steroid or antihistamine for their nasal symptoms and are unable to remain on a constant dose for four weeks prior to visit 1 or for the duration of the study.
• Females who are pregnant or lactating or are likely to become pregnant during the study or are less than 8 weeks postpartum. Women of childbearing age may be included if, in the opinion of the investigator, they are taking adequate contraceptive measures.
• Subjects who are unable to follow the instructions within this protocol or known inability to attend all clinic visits within the intervals stated.
• Subjects who have participated in a clinical trial involving an investigational or marketed drug within four weeks of visit one.