ABSTRACT
A study of mediator cells by nasal scraping method was performed for the first time in Thai population i.e. 154 chronic rhinitis patients and 43 healthy volunteer with no nasal symptoms. There were 67 males and 87 females, ages ranged from 8 – 70 years old with the average of 35.5 in the chronic rhinitis group. In the normal volunteer group, there were 21 males and 22 females, ages ranged from 17 – 74 years old with the average of 35. All chronic rhinitis were skin tested by intracutaneous method to a panel of common inhalants. The result of the skin test we graded into 0 – 4+ If the patients had 2+ – 4+ skin test result, they were classified as having allergic rhinitis (AR), while patients who had 0 – 1 were classified as non-allergic rhinitis (NAR). The average number of basophilic metachromatic cells (BMC) in normal volunteers, AR and NAR patients were 2.35 + 10.73 (0 – 57), 121.74 + 198.73 (0 – 1,177) and 11.33 + 32.05 (0 – 117) cells respectively. This findings confirm that AR patients have more BMC on their nasal surface than NAR patients and normal people. When comparing the average number of BMC according to the skin test result in chronic rhinitis patients we found that the average number of BMC in patients with 0, 2+, 3+ and 4+ skin test results were 11.33 + 32.05, 54.54 + 100.49, 110.00 + 84.68 and 135.71 + 212.54 cells respectively. Statistical analysis showed that the number weaker positive and negative results. The sensitivity of nasal scraping method in diagnosing AR was found to be 61.27 percent with the specificity of 90.91 percent, the positive predictive value was 94.56 percent and the efficiency of test was 69.54 percent. We concluded that the study of BMC by nasal scraping method is easy to perform with minimal trauma to the patient, the instrument used is simple and less expensive, the interpretation of result is also accurate and can be repeated. Therefore this method should be considered as another tool to diagnose AR especially in the place where skin test is not available.