Late Local Urticaria as a Long-term Sequela of Allergen-Specific Immunotherapy

Local reaction to allergen-specific immunotherapy (SIT) usually appears within 30 minutes, but cases with exercise-induced urticaria at the SIT site 2-3 weeks after the last allergen injection have been reported. A 28-year-old man was treated with house dust mite-SIT for 5 years, due to asthma when he was an 11-year-old boy. On a treadmill exercise test for 50 minutes, erythema, swelling, and pruritus occurred at the SIT site, which lasted for one hour. There was no evidence of complement activation, and the skin biopsy specimens showed no apparent difference between the lesion and normal sites in the distribution of inflammatory cells and in mast cell degranulation. However, the morphine, but not the histamine, skin test responses were increased after the exercise. There must be a remaining long-term sequela of the SIT, including an increased releasability of mast cells, even after more than 10 years.

Airway collapsibility indicating indication excessive airway narrowing in asthma / 천식및알레르기

BACKGROUND: It has been sugested that excessive airway narrowing in asthma may be detected by a decrease in forced vital capacity (FVC). A volume differrence between slow vital capacity (SVC) and FVC may be used as a surrogate index of airway collapse. OBJECTIVE: To investigate the relationship between an airway collapsibility index (CI) and airflow limitation or airway hyperresponsiveness in asthma. METHODS: Forty-six patients with suspected asthma and 21 normal control subjects were enrolled. CI was defined as a difference between SVC and FVC, and measured before and after a methacholine (MCh) bronchoprovocation test. Positive response to MCh was defined as a fall of FEV1 by more than 12%. RESULTS: CI significantly increased from 1.10+/-3.86% to 5.52+/-7.91% after MCh in the positive MCh group (n=19, p<0.01). Not only FVC but also SVC was significantly decreased after MCh. One-fifth of the decrease in FVC was caused by the increase in CI. Both FVC and SVC were significantly related to baseline FEV1 values and in percent change after MCh. Although CI was also significantly related to FEV1 in percent change after MCh. CI was significantly higher in the positive MCh group than in the control and was not significantly related to baseline FEV1 values. Furthermore, the relationship of CI values between before and after MCh was significant (r=0.622, p<0.01). CI was not significantly different according to the severity of MCh-PC20. CONCLUSION: Because the relationship between CI and the severity of airflow limitation or MCh-PC20 was less significant. CI may be better than FVC to represent the characteristic of excessive airway narrowing in asthma.

A status of occupational asthma in Korea through the cases reported to the Occupational Asthma Surveillance Center / 천식및알레르기

BACKGROUND: Since asthma caused by toluene diisocyanate (TDI) was reported at a polyurethane paint factory, occupational asthma there has been increasing concern of in both allergic and occupational health. However, the statistics of occupational asthma did not reflected its seriousness because of many barriers related to legal reporting. Since fild a voluntary report from a clinician sent directly to a surveillance center would allow more cases to be filed without any disadvantage to workers and employers, we developed a surveillance system to facilitate the reporting of occupational asthma. METHODS: Allergists and pulmonary physicians were asked to report to the Occupational Asthma Surveillance Center (OASC) using a mail, fax or e-mail if work-related asthma was diagnosed. A claimed case for occupational asthma to the Occupational Health Research Institute was also included. The OASC contacted the workers by phone and investigated the workplace if necessary. The reported cases from October, 1998 to November, 1999 were analysed. RESULTS: Thirty-three cases were reported with 29 males and four females. The mean age was 44 and the mean latency period was 5.4 years. Twenty-one cases were caused by a known allergen inducer with objective evidence. The causative agents included TDI in 45.5 % (15), followed by reactive dye in 24.2 % (8), welding fume (2), formaldehyde (1), paint (1), toluene (1), styrene (1), exhaustive gas (1), and wood dust (1). Among these cases, there were seven dyers, four painters, three machine operators and furniture finishers, two assemblers and tanneries. Eighteen cases had claimed Workers Compensation Insurance and all were accepted. The reasons for not claiming Insurance included ignorance (28.5 %), feat of job dismissal (23.8%), other reasons (9.5 %), agreement with the employer (14.3 %) and employer himself (9.5 %). CONCLUSION: The OASC by allergists was an effective system to find unreported cases and to provide a prevention strategy of occupational asthma. Occupational asthma was mostly caused by TDI and reactive dye. Painters and dyers were the most common occupations causing occupational asthma. Only half of occupational asthma patients claimed compensation because of workers' ignorance and fear of being fired.

Ozon-induced airway hyperresponsiveness of rat tracheal smooth muscle / 천식및알레르기

BACKGROUND: Ozone (03) induces airway inflammation and hyperresponsiveness which are characteristic features of asthma. There have been few studies observing O3-induced increase in responsiveness of rat airway muscle. Objectives: The aims of this study were to develop an O3-induced nonallergic asthma model using rat tracheal smooth muscle (TSM) and to evaluate the role of airway epithelium on the modulation of muscle responsiveness. METHOD: Five groups of 20 male Sprague-Dawley(SD) rats were exposed to filtered air including 0.12, 0.5, 1.0, or 2.0 ppm 03 for 1 hour. Thirty minutes after the exposure, bronchoalveolar lavage (BAL) and isometric contractile responses of the isolated tracheal ring segments to KCI, acetylcholine (ACh), and electrical field stimulation (EFS) were measured. RESULTS: The percent age of neutrophils was significantly higher and that of alveolar macro-phages in BAL fluid was significantly lower in 2.0 ppm O3-exposed rats than in the control. There were no significant differences in the maximal contractile responses of TSM to KC1, ACh, EFS and in the sensitivity to ACh (ACh-EC50) and EFS (EFS-EC50) between the control group and the ozone exposed group. ACh-EC50 and EFS-EC50 were correlated positively with the percent age of neutrophils and inversely with that of macrophages. Removal of epithelium significantly increased the sensitivity to ACh in O3-exposed group, but not in the control group. CONCLUSION: These findings indicate that O3 induces neutrophilic airway inflammation, but not an increased sensitivity of TSM to ACh or EFS in SD rats. However, O3-induced epithelial damage may be associated with increased muscle response.

Clinical significance of forced expiratory wheezing in chronic airflow obstruction / 천식및알레르기

BACKGROUND: Wheezing which is defined as a continuous sound with a musical quality is commonly auscultated in patients with chronic obstructive airway diseases. The correlation between wheezing and airway obstruction is unclear. OBJECTIVE: This study was designed to evaluate the relationships among wheezing, severity of airway obstruction, and pulmonary function tests. METHOD: Forty-one subjects were examined by the same observer. Wheezing during normal breathing and maximal forced exhalation, was auscultated respectively. Posterior lung bases were auscultated bilaterally with the seated patient taking repeated inspiratory capacity breaths through an open mouth. To quantify wheezing intensity, a regional score was assigned for each area after a minimum of 3 breaths, according to the following scale: zero, no wheezing heard: one, faint or intermittent wheezes: two, moderate wheezing during every expiration: three, loud wheezing during every expiration. The lung function tests by standard pneumotachograph were performed by skilled technicians. RESULTS: Wheezing was auscultated more in forced exhalation than in normal breathing in patients with asthma and COPD [8/9(88%) vs 1/9(11%), p<0.01 ll/15(73%) vs 1/15(6%), p<0.05)]. Forced expiratory wheezes group (n=25) compared to no wheezes group (n=16) had significantly lower FEVl (75+-5.8% vs 95.6+-6.6%, p<0.05). Compared to no wheezes group, the group with forced expiratory wheezes had lower FEV1 and FEV1/FVC (50.4+- 21.3% vs 81.15+-27.7%, 70.4+-22.4% vs 92.5+-19.3%, respectively, p<0.05). Bronchial asthma compared with COPD tended to have higher wheezing scores (Wheeze scores Bronchial asthma 3.5 vs COPD 2.4, p=0.08). Wheezing scores were correlated to FEV1 (normal breathing: r=-0.35, p<0.05: forced exhalation: r=-0.45, p<0.05), but no differences were found in wheezing incidence according to severity of airway obstruction. CONCLUSION: These findings suggest that wheezing on maximal forced exhalation may be a useful physical indicator for evaluating the severity of airway obstruction.