[in Japanese]

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We have often experienced that values of respiratory function test (flow-volume curves) differ depending on the posture of the subjects. To investigate which of the postures, standing or sitting, is more appropriate to measure flow-volume curve in order to prospect asthma attacks in children, we measured flow-volume curves during forced expiration in 122 asthma patients who were followed up at our out-patient clinic. The measurements were done three times each in standing position at the out-patient clinic, and sitting position at the respiratory function laboratory for each patient. The equipment used at the laboratory was only for sitting position, while the equipment used at the out-patient clinic was basically for standing position. Then, we estimated %FVC, and FEV_1.0%, %_v50, and %_v25 in each position, and compared the respective parameters in different positions. %FVC and FEV_1.0% estimated in standing position were not significantly different from those in sitting position, while %_v50 and %_v25 in standing position were significantly higher than those in sitting position, respectively. %_v50 and %_v25 in both standing and sitting position of the patients who had asthma attacks two weeks before and/or after the measurement were significantly lower than those who did not have attacks in those period. However, those parameters estimated in sitting position varied widely from patient to patient. Moreover, they were significantly lower in younger patients than in older patients even in the group without attacks. Thus, we concluded that flow-volume curves measured in standing position were more appropriate as an indicator of the control of pediatric asthma patients than those measured in sitting position, especially in younger patients.

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Histamine release test (HRT) is one of popular and frequently used in vitro tests for identifying causative allergens in patients with allergic disease. Five allergens (egg white, cows milk, wheat, rice, and soy) in 54 children with food allergy were examined by two methods of HRT (Lucica HRT^®, Shionogi^®) and CAP-RAST^®. Positive rate of CAP-RAST^® exceeded that of both methods of HRT. Although in patients with early phase response in allergic reaction, positive rate of HRT exceeded the results of patients without any symptoms. Furthermore, HRT revealed lower sensitivity and higher specificity than CAP-RAST^® in egg white and cows milk.
In addition, we evaluated histamine release to anti-IgE antibody. Seven anti-IgE non releasers were found in 54 patients. All anti-IgE non releasers aged under two years old (0.57±0.8years) and their serum total IgE levels were relatively lower (116±72IU/ml) compared with those of releasers. Also, three of seven non releasers manifested early phase reaction to egg white and/or cows milk.
On the other hand, three allergen (egg white) non releasers were found in 21 patients who showed early phase reaction to egg white. Their percentage of eosinophil in peripheral blood leukocytes were relatively higher than those of releasers (p<0.01). The mechanism and pathogenesis of anti-IgE and allergen non releasers have not been elucidated yet.
HRT might be useful in predicting clinical symptoms. However, there is a limitation of its usefulness. Therefore, we should be careful in choosing clinical test in detecting causative allergens.

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