Background: The forced oscillation technique (FOT) is a noninvasive method that is used to measure respiratory mechanics, including respiratory resistance and reactance at multiple frequencies. The advantage of FOT over spirometry is that FOT does not require forced expiratory maneuvers. Moreover, a new FOT machine called MostGraph (Chest Co. Ltd., Tokyo, Japan), has been developed in Japan, and can be used clinically to diagnose and monitor asthma. The purpose of this study is to show the standard of FOT measured with MostGraph in adult Japanese asthmatics. Methods: From our outpatient clinic, we recruited 151 stable asthmatics who were being treated with inhaled corticosteroids at the time of the study. For each subject, we measured the fraction of exhaled nitric oxide (FeNO) by using a chemiluminescent nitric oxide analyzer (Sievers280, GE, Boulder, Co); we determined the levels of forced expiratory volume in 1s (%FEV_1) and maximum midexpiratory flow rate (%MMF) by using spirometory; and we measured resistance at 5Hz (R5), resistance at 20Hz (R20), R5-R20, reactance at 5Hz (X5), frequency of resonance (Fres), and low-frequency reactance area (ALX), by using a MostGraph FOT machine. Results: Each of the FOT parameters measured by using the MostGraph machine was significantly correlated with %FEV_1 and %MMF (p<0.001), with Fres showing the strongest association. Three of the FOT parameters, X5, Fres, and ALX, were significantly associated with the subject's age (p=0.01, p<0.001, p<0.001, respectively), and all FOT parameters were significantly associated with the subject's body mass index (BMI) (p<0.001 to p=0.018). The results of multiple regression analyses between FOT parameters and FEV_1, age, BMI, and FeNO, showed that Fres was significantly associated with FEV_1 (p<0.001) and BMI (p<0.001). From the results of the simple linear regression between Fres and FEV_1, we estimated that Fres values of 17.5Hz corresponded to %FEV_1 values of 60%; Fres values of 1l.3Hz corresponded to %FEV_1 values of 80%; and Fres values of 4.94Hz corresponded to %FEV_1 values of 100%. Conclusion: FOT parameters measured by using a MostGraph machine can be used successfully to assess the level of airflow limitation in adult stable asthmatics.

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Background: Airway inflammation is a fundamental feature of bronchial asthma. We examined whether educational guidance using a text on pathophysiology and management of asthma modify airway inflammation of severe asthma. Methods: Eighteen severe persistent asthmatics were enrolled in this study. Evaluation on asthma control using Asthma Control Test (ACT), Asthma Health Questionnaire (AHQ)-Japan), FEV_1, percentages of eosinophils and neutrophils in induced sputum were analyzed before and 4 weeks after patient education process. Results: Following educational guidance, ACT and FEV_1 did not improve, but AHQ score significantly improved. Furthermore, percentage of eosinophils in sputum significantly reduced. On the contrary, the percentage of neutrophils in sputum was not changed. In accordance with this lack of the change in neutrophil numbers, neutrophil chemoattractants including IL-8 or CXCR3 in the induced sputum did not change before and after patient guidance. Conclusion: Educational guidance using a text on pathophysiology and management of asthma provides some effects on quality of life in asthmatic patients and eosinophilic inflammation, however, this procedure does not modify the control status of asthma and neutrophilic inflammation seen with severe asthma.

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Background: Treatment of infantile and childhood atopic dermatitis needs special consideration compared to adult's counterpart. Repeated exposure to irritation by slaver or rubbing makes facial lesions difficult to treat in infants and children. We considered the deterioration factor and the treatment that we performed. Methods: We considered 6 infantile and childhood atopic dermatitis who had severe condition on their face. Result: All the patients needed enough application of topical steroids. Exacerbation of atopic dermatitis masked concomitant skin infection such as impetigo or Kaposi's varicelliform eruption. Guardian usually hesitated periorbital and perioral application of topical steroids and tacrolimus. In order to obtain the guardian's understanding and cooperation, it was very important to establish a good doctor/guardian relationship by educational approach including an enough explanation about treatment policy. Conclusion: It was important for the treatment of infantile and childhood atopic dermatitis to identify and eliminate triggering factors. And we need to obtain the guardian's understanding and cooperation for our treatment policy.

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A 30-year-old woman had refractory asthma. She had also experienced twice severe anaphylaxis episodes after ingesting peaches. The patient was extremely wary about reoccurrence of anaphylaxis and avoided ingesting any fruits, including peaches. She visited our hospital for testing and treatment for asthma and the peach allergy. Skin and serologic testing showed that she had a severe allergy to house dust, mites, and peaches. The food challenge test results showed that ingesting 6.5g of the peach fruit induced dyspnea in the patient. Her asthma could not be controlled despite treatment involving a leukotriene receptor antagonist and combination inhalation of high-dose salmeterol xinafoate/fluticasone propionate. We advised the patient to keep strict avoidance ingesting peaches because of her food allergy. However, she hoped to overcome her food restrictions, especially those for fruits. We initiated treatment involving the recombinant humanized monoclonal anti-IgE anti-body omalizumab (150mg, once a month) to ensure that the asthma was controlled well and to improve the patient's diet. The asthmatic symptoms ameliorated, and the peak expiratory flow increased in a short time. We gradually reduced the restriction on peach consumption. This was achieved by rechallenging the patient with increasing doses of 290mg of the peach fruit and was initiated at 28 weeks after starting omalizumab therapy. The restriction on peach consumption was lifted eventually, and the patient did not experience any allergic symptoms subsequently on ingesting peaches. Thus, for our patient, omalizumab therapy was highly effective in achieving remission from both asthma and peach allergy.

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