Factors determining changes in egg white-specific IgE in children agedyounger than 2 years with sensitization to egg white

Purpose@#Food sensitization to egg white (EW) peaks during early childhood, after which some children with sensitization to EW outgrow food sensitization, while others develop an increased degree of sensitization to EW. We investigated factors determining changes in EW-specific IgE in children under 2 years of age. @*Methods@#Among children under 2 years of age with atopic dermatitis or food allergy who visited Asan Medical Center from March 2018 to September 2021, a total of 172 sensitized to EW were enrolled. Serum specific IgE to EW, ovalbumin and ovomucoid, and specific IgG4 to EW and ovomucoid were measured at 0, 6, and 12 months. An increase in EW-specific IgE was defined as an increased level of EW-specific IgE after 12 months from baseline. Multiple logistic regression analysis was performed to identify factors determining an increase in EW-specific IgE. @*Results@#Of the 172 children, 85 had complete data on serum specific IgE and specific IgG4 during a period of 12 months. The levels of EW-specific IgE were decreased in 51 subjects (60.0%), while they were increased in 34 subjects (40.0%). Introduction of baked eggs had a protective effect against an increase in EW-specific IgE levels during a period of 12 months (adjusted odds ratio, 0.148; 95% confidence interval, 0.022–0.983). @*Conclusion@#Introduction of the baked egg can prevent an increase in EW-specific IgE during early childhood. Further studies are needed for the long-term effect of baked egg on the natural course of EW sensitization.

Serum IgE specific to egg white and its components and open baked eggoral food challenge tests in children younger than 6 years

Purpose@#Sixty to eighty percent of children with egg allergy are able to tolerate eggs in baked form. The purpose of this study was to evaluate the clinical usefulness and diagnostic value of measurements of IgE specific to egg white, ovalbumin, and ovomucoid for reactivity to baked egg in children with sensitivity to egg. @*Methods@#Two hundred seventeen children with suspected egg allergy underwent open food challenges with baked egg (in the form of muffins). The outcomes of the challenges were compared to the serum concentrations of IgE specific to egg white, ovalbumin, and ovomucoid by using ImmunoCAP. @*Results@#There were no statistically significant differences in levels of IgE specific to egg white, ovalbumin, and ovomucoid between the baked egg challenge positive and negative groups younger than 2 years (n = 163). However, significant differences were observed between the challenge positive and negative groups in 54 subjects aged 2 to 5 years (all P < 0.05). The optimal cutoff points of egg white, ovalbumin, and ovomucoid specific IgE levels among children aged 2 to 5 years were 12.40 kU A/L (sensitivity 79%, specificity 66%), 4.07 kU A/L (sensitivity 88%, specificity 58%), and 3.65 kU A/L (sensitivity 77%, specificity 62%), respectively. @*Conclusion@#The level of IgE specific to egg white and its components can predict the reactivity to baked egg in children aged 2 to 5years.

Innate Type 2 Response to Aspergillus fumigatus in a Murine Model of Atopic Dermatitis–like Skin Inflammation

Background@#Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mediated by T helper type 2 (Th2) cells in acute phase. Group 2 innate lymphoid cells (ILCs) play a role in the initiation of the Th2 response. Although mold exposure is associated with the development of AD, studies on the underlying mechanisms are lacking. This study investigated whether group 2 ILCs are involved in inflammation in AD-like skin induced by Aspergillus fumigatus (Af). @*Methods@#We investigated changes of group 2 ILCs population in Af-induced AD-like skin lesions. To induce AD-like skin lesions, Af extracts were applied to the dorsal skin of BALB/c and Rag1−/− mice five times per week, with repeat exposures at 2-week intervals. @*Results@#The clinical parameters were higher in the Af-treated group than in the control group. Histologic findings revealed epiderrmal and dermal thickening as well as eosinophil and mast cell infiltration into the skin of Af-treated mice. Populations of group 2 ILCs in the skin were also significantly higher in the Af-treated group. In addition, interleukin-33 mRNA expression was significantly higher in the skin lesions of the Af-treated mice. In the Rag1−/− mice lacking mature lymphocytes, AD-like skin lesions were still induced by Af and ILCs depletion using an anti-CD90.2 mAb lowered the Af-induced inflammatory response. @*Conclusions@#Group 2 ILCs may play a role in a murine model of Af-induced AD-like skin lesions.

Innate Type 2 Response to Aspergillus fumigatus in a Murine Model of Atopic Dermatitis–like Skin Inflammation

Background@#Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mediated by T helper type 2 (Th2) cells in acute phase. Group 2 innate lymphoid cells (ILCs) play a role in the initiation of the Th2 response. Although mold exposure is associated with the development of AD, studies on the underlying mechanisms are lacking. This study investigated whether group 2 ILCs are involved in inflammation in AD-like skin induced by Aspergillus fumigatus (Af). @*Methods@#We investigated changes of group 2 ILCs population in Af-induced AD-like skin lesions. To induce AD-like skin lesions, Af extracts were applied to the dorsal skin of BALB/c and Rag1−/− mice five times per week, with repeat exposures at 2-week intervals. @*Results@#The clinical parameters were higher in the Af-treated group than in the control group. Histologic findings revealed epiderrmal and dermal thickening as well as eosinophil and mast cell infiltration into the skin of Af-treated mice. Populations of group 2 ILCs in the skin were also significantly higher in the Af-treated group. In addition, interleukin-33 mRNA expression was significantly higher in the skin lesions of the Af-treated mice. In the Rag1−/− mice lacking mature lymphocytes, AD-like skin lesions were still induced by Af and ILCs depletion using an anti-CD90.2 mAb lowered the Af-induced inflammatory response. @*Conclusions@#Group 2 ILCs may play a role in a murine model of Af-induced AD-like skin lesions.

Associated Factors for Asthma Severity in Korean Children: A Korean Childhood Asthma Study

PURPOSE: Childhood asthma has a considerable social impact and economic burden, especially in severe asthma. This study aimed to identify the proportion of childhood asthma severity and to evaluate associated factors for greater asthma severity. METHODS: This study was performed on 667 children aged 5–15 years with asthma from the nationwide 19 hospitals in the Korean childhood Asthma Study (KAS). Asthma was classified as mild intermittent, mild persistent, and moderate/severe persistent groups according to the National Asthma Education and Prevention Program recommendations. Multinomial logistic regression models were used to identify the associated factors for greater asthma severity. RESULTS: Mild persistent asthma was most prevalent (39.0%), followed by mild intermittent (37.6%), moderate persistent (22.8%), and severe persistent asthma (0.6%). Onset later than 6 years of age (adjusted odds ratio [aOR], 1.69 for mild persistent asthma; aOR, 1.92 for moderate/severe persistent asthma) tended to increase asthma severity. Exposure to environmental tobacco smoke (aOR, 1.53 for mild persistent asthma; aOR, 1.85 for moderate/severe persistent asthma), and current dog ownership with sensitization to dog dander (aOR, 5.86 for mild persistent asthma; aOR, 6.90 for moderate/severe persistent asthma) showed increasing trends with greater asthma severity. Lower maternal education levels (aOR, 2.32) and no usage of an air purifier in exposure to high levels of outdoor air pollution (aOR, 1.76) were associated with moderate/severe persistent asthma. CONCLUSIONS: Modification of identified environmental factors associated with greater asthma severity might help better control childhood asthma, thereby reducing the disease burden due to childhood asthma.

Seasonal patterns and etiologies of croup in children during the period 2010–2015: A multicenter retrospective study

PURPOSE: Croup is known to have epidemics in seasonal and biennial trends, and to be strongly associated with epidemics of parainfluenza virus. However, seasonal and annual epidemics of croup have not been clearly reported in Korea. This study aimed to examine the seasonal/annual patterns and etiologies of childhood croup in Korea during a consecutive 6-year period. METHODS: Pediatric croup data were collected from 23 centers in Korea from 1 January 2010 to 31 December 2015. Electronic medical records, including multiplex reverse transcription polymerase chain reaction (RT-PCR) results, demographics and clinical information were cross-sectionally reviewed and analyzed. RESULTS: Overall, 2,598 childhood croup patients requiring hospitalization were identified during the study period. Among them, a total of 927 who underwent RT-PCR were included in the analysis. Males (61.5%) predominated, and most (63.0%) of them were younger than 2 years of age (median, 19 months; interquartile range, 11–31 months). Peak hospitalization occurred in 2010 and 2012 in even-numbered years, and parainfluenza virus (PIV, 39.7%) was the most common cause of childhood croup requiring hospitalization, followed by respiratory syncytial virus (14.9%), human rhinovirus (12.5%), Mycoplasma pneumonaie (10.6%), and human coronavirus (7.3%). CONCLUSION: It is concluded that croup hospitalization has a biennial pattern in even-numbered years. PIV may be the most common cause of childhood croup; however, croup epidemics could be attributed to other viruses.

ERRATUM: Correction of Funding Resource: Development of Aspergillus fumigatus-induced chronic atopic dermatitis mouse model

In this article, the funding resource was misprinted unintentionally.

Development of Aspergillus fumigatus-induced chronic atopic dermatitis mouse model

PURPOSE: Atopic dermatitis (AD) is the most common chronic and relapsing inflammatory skin disease with skin barrier defects and altered immune responses. Chronic inflammation leads to irreversible fibrosis in the skin and there is no treatment to completely abolish the inflammation and fibrosis. To prevent or treat the chronic process of AD, it is necessary to develop a murine model of AD that reflects the chronic process to identify the mechanism. The aims of this study were to develop a chronic AD model with a crude extract Aspergillus fumigatus (Af) antigen. METHODS: We applied Af extract (40 µg) epicutaneously to the dorsal skin of BALB/c mice for 5 consecutive days per week during a period of 5 weeks for a chronic AD model, and 5 consecutive days repeatedly with 2 weeks interval for an acute AD model. RESULTS: The clinical score and transepidermal water loss were more increased in the chronic AD model than in the acute AD model. Histologic findings showed that more increased epidermal thickness, neutrophil infiltration and hyperkeratosis in the chronic model than in the acute model. Skin fibrosis was more prominent in the chronic model than in the acute model. The mRNA expression levels of transforming growth factor (TGF)-β, thymic stromal lymphopoietin, and interleukin-33 were increased in the skin of the chronic model compared to the acute model. The levels of total IgE, Af-specific IgE, IgG1, and IgG2a were significantly increased in the chronic model compared to controls. CONCLUSION: The Af-induced chronic AD model showed prominent fibrosis and increased TGF-β expression in the skin, which suggests that these models may be useful in the research for the mechanism of the chronic process in AD.

Outcomes of drug provocation tests in Korean children with suspected drug hypersensitivity reaction

PURPOSE: Drug provocation tests (DPT) are the gold standard for confirming the diagnosis of drug hypersensitivity reactions (DHRs). However, there are little studies of DPT in children. The purpose of this study was to evaluate DPT results and safety as diagnostic methods of DHR in Korean children. METHODS: We reviewed the medical records of 39 children under 18 years of age with a suspected DHR and performed DPT between January 2010 and May 2016 at Asan Medical Center. RESULTS: Total 110 DPT were performed in 39 children (20 boys and 19 girls) with a history of DHR. Clinical presentation of DHR included skin rash (n=7), pruritus (n=3), urticaria (n=18), angioedema (n=19), dyspnea (n=5), hoarseness (n=1), hypothermia (n=1), and anaphylaxis (n=5). The median age at the time of DPT was 9 years. Positive DPT were observed in 21 of 39 children (53.8%) and 28 of 110 cases (25.5%). Drugs causing positive reactions were acetaminophen in 50% (9 of 18), nonsteroidal anti-inflammatory drugs in 29.2% (14 of 48), cephalosporin in 9.1% (1 of 11), trimethoprim/sulfamethoxazole in 50% (1 of 2), local anesthetics in 10% (1 of 10), and others (levodropropizine and idursulfase) in 15.4% (2 of 13). There was no statistical difference between children who had positive and negative results in sex, age, personal and parental history of allergic disease, eosinophil count, or total IgE level. Children with positive DPT did not develop anaphylaxis during the DPT procedure. CONCLUSION: Drug provocation test is safe, and it can be considered in children with suspected DHRs.

Prevalence and clinical manifestations of macrolide resistant Mycoplasma pneumoniae pneumonia in Korean children / 소아과

PURPOSE: Macrolide resistance rate of Mycoplasma pneumoniae has rapidly increased in children. Studies on the clinical features between macrolide susceptible-M. pneumoniae (MSMP) and macrolide resistant-M. pneumoniae (MRMP) are lacking. The aim of this study was to identify the macrolide resistance rate of M. pneumoniae in Korean children with M. pneumoniae penupmonia in 2015 and compare manifestations between MSMP and MRMP. METHODS: Among 122 children (0–18 years old) diagnosed with M. pneumoniae pneumonia, 95 children with the results of macrolide sensitivity test were included in this study. Clinical manifestations were acquired using retrospective medical records. RESULTS: The macrolide resistant rate of M. pneumoniae was 87.2% (82 of 94 patients) in children with M. pneumoniae pneumonia. One patient showed a mixed type of wild type and A2063G mutation in 23S rRNA of M. pneumoniae. There were no significant differences in clinical, laboratory, and radiologic findings between the MSMP and MRMP groups at the first visit to our hospital. The time interval between initiation of macrolide and defervescence was significantly longer in the MRMP group (4.9±3.3 vs. 2.8±3.1 days, P=0.039). CONCLUSION: The macrolide resistant rate of M. pneumoniae is very high in children with M. pneumoniae pneumonia in Korea. The clinical manifestations of MRMP are similar to MSMP except for the defervescence period after administration of macrolide. Continuous monitoring of the occurrence and antimicrobial susceptibility of MRMP is required to control its spread and establish strategies for treating second-line antibiotic resistant M. pneumoniae infection.

Clinical issues regarding increased macrolide-resistant Mycoplasma pneumoniae in children

No abstract available.

The First Successful Lung Transplantation in a Korean Child with Cystic Fibrosis

Cystic fibrosis (CF) is an autosomal recessive inherited multisystem disorder caused by mutations of the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Respiratory failure remains the most frequent cause of morbidity and mortality. Lung transplantation is the only option to treat end-stage lung disease. Very few cases of CF occur in Koreans. We report the case of a 12-year-old girl with respiratory failure due to CF who underwent lung transplantation. She had been diagnosed with CF 8 years previously after being treated for recurrent Pseudomonas aeruginosa pneumonia and malnutrition based on sweat chloride concentrations and the CFTR protein gene mutation test. Progression to end-stage lung disease and respiratory failure led to registration with the Korean Network for Organ Sharing. She underwent successful double lung transplantation in 2014. Although she has diabetes mellitus and chronic kidney disease, she has a better quality of life and a prolonged life expectancy.

The Different Clinical Aspects of Pediatric Primary Airway Tumors in the Larynx, Trachea, and Bronchi

Primary airway tumors are rare in children and no literature reviewed their characteristics each location. We evaluate the clinical characteristics and outcomes of Korean children with primary airway tumors, from the larynx to bronchi. A retrospective chart review of children with primary tumors of the larynx, trachea, and bronchi at Asan Medical Center from January 2000 to July 2016 was conducted. Nineteen children were diagnosed with primary airway tumors of the larynx (47.4%), trachea (10.5%), and bronchi (42.1%). Median follow-up duration was 2.8 years and there were recurrences in 21.1%. Laryngeal tumors were associated with a younger median age at onset (2 months) and diagnosis (4 months), and most were relatively small (median size = 5.3 mm) and symptomatic. Tracheal and bronchial tumors were found in older children (age at onset and diagnosis > 11 years) and large (> 15.0 mm). Most (75%) patients with bronchial tumors were asymptomatic and all the patients with tracheal tumors were symptomatic. This study suggests that we should consider different the locations in primary airway tumor based on the age at onset and diagnosis, initial symptoms or signs, and size of tumor.

The Interaction Between Prenatal Exposure to Home Renovation and Reactive Oxygen Species Genes in Cord Blood IgE Response is Modified by Maternal Atopy

PURPOSE: Although home renovation exposure during childhood has been identified as a risk factor for the development of allergy, there is limited information on the association between prenatal exposure to home renovation and cord blood (CB) IgE response. The aims of this study were to identify the effect of prenatal exposure to home renovation on CB IgE levels, and to investigate whether this exposure interacts with neonatal genes and whether the effect can be modified by maternal atopy. METHODS: This study included 1,002 mother-neonate pairs from the COhort for Childhood Origin of Asthma and allergic diseases (COCOA). Prenatal environmental factors were collected using a questionnaire. The levels of CB IgE were measured by the ImmunoCAP system, and DNA was extracted from CB. RESULTS: Exposure to home renovation during the prenatal period was associated with significantly higher levels of CB IgE only in neonates from atopic mothers, and the effect of renovation exposure on CB IgE levels persisted from 31 months before birth. Furthermore, prenatal exposure to home renovation increased the risk of CB IgE response interacting with polymorphisms of NRF2 and GSTP1 genes only in neonates from atopic mothers. CONCLUSIONS: Maternal atopy modified the effect of prenatal exposure to home renovation on CB serum IgE response as well as the interaction between the exposure and neonatal genes involved in the oxidative stress pathway. These findings suggest that the genetically susceptible offspring of atopic mothers may be more vulnerable to the effect of prenatal exposure to home renovation on the development of allergy.

Pediatric adverse drug reactions collected by an electronic reporting system in a single tertiary university hospital

PURPOSE: The incidence of adverse drug reactions (ADRs) is increasing. However, studies on the prevalence of ADRs in children are rare. The aim of this study was to investigate the causative drugs and clinical features of ADRs for children in a tertiary university hospital of Korea. METHODS: We retrospectively collected ADRs by a computerized self-reporting system in Asan Medical Center. ADRs of children under the age 18 were collected from January 2005 to August 2015, and we analyzed only ADRs containing current symptoms among total ADR data. RESULTS: A total of 1,408 ADR cases were reported, There were 764 male (54.3%) and 644 female patients (45.7%), and the mean age was 11.5±5.8 years (range, 0–18 years). Antibiotics (n=479, 34.0%) were the most common causative drugs, followed by tramadol (n=173, 12.3%), nonsteroidal anti-inflammatory agents (NSAIDs) and acetylsalicylic acid (n=103, 7.3%), narcotics (n=91, 6.5%), antineoplastics (n=87, 6.2%), and sedatives (n=82, 5.8%). The most common clinical features were skin manifestations (n=500, 34.4%). Gastrointestinal symptoms (n=435, 29.9%) were the second most common clinical features, followed by neuropsychiatric symptoms (n=155, 10.7%) and respiratory symptoms (n=123, 8.5%). Among antibiotics, glycopeptides (n=110, 23.0%), third-generation cephalosporins (n=83, 17.3%), and penicillin/β-lactamase inhibitors (n=60, 12.7%) were the most frequently reported causative drugs. CONCLUSION: Antibiotics were the most reported common causative drugs of ADRs in children, followed by tramadol, NSAID, and narcortics. Compared with adults, the prevalence of contrast medium-induced ADR was lower in children with a higher prevalence of sedative-associated ADR. Greater attention to possible ADRs in children is needed among medical personnel.

Translation and linguistic validation of Korean version of the Test for Respiratory and Asthma Control in Kids instrument

PURPOSE: We aimed to translate the Test for Respiratory and Asthma Control in Kids (TRACK) instrument into Korean, with subsequent linguistic validation. METHODS: The multistep process of forward translation, reconciliation, back-translation, cognitive debriefing, and proofreading of the Korean version of the TRACK was completed. RESULTS: Two bilingual medical personnel independently translated the original English version of the TRACK into Korean one. After moderating the translation into a single reconciled one, 4 other bilingual persons were invited to translate the Korean draft back into an English one. Discrepancies between the original English version and the back-translated one were reviewed, and the need to modify the reconciled Korean draft was discussed. Twenty caregivers of asthmatic children took part in interviews that examine the appropriateness of the Korean version of the TRACK. The feedback from caregivers were then reviewed by a panel of pediatric allergists and reflected in the final Korean version. The document was finally proofread to check the spelling, grammar, layout and formatting. CONCLUSION: Translation and linguistic validation of the Korean version of the TRACK instrument were completed.

The First Successful Heart-Lung Transplant in a Korean Child with Humidifier Disinfectant-Associated Interstitial Lung Disease

From 2006 to 2011, an outbreak of a particular type of childhood interstitial lung disease occurred in Korea. The condition was intractable and progressed to severe respiratory failure, with a high mortality rate. Moreover, in several familial cases, the disease affected young women and children simultaneously. Epidemiologic, animal, and post-interventional studies identified the cause as inhalation of humidifier disinfectants. Here, we report a 4-year-old girl who suffered from severe progressive respiratory failure. She could survive by 100 days of extracorporeal membrane oxygenation support and finally, underwent heart-lung transplantation. This is the first successful pediatric heart-lung transplantation carried out in Korea.

A Multicenter Retrospective Case Study of Anaphylaxis Triggers by Age in Korean Children

PURPOSE: Although anaphylaxis is recognized as an important, life-threatening condition, data are limited regarding its triggers in different age groups. We aimed to identify anaphylaxis triggers by age in Korean children. METHODS: We performed a retrospective review of medical records for children diagnosed with anaphylaxis between 2009 and 2013 in 23 secondary or tertiary hospitals in South Korea. RESULTS: A total of 991 cases (mean age=5.89±5.24) were reported, with 63.9% involving patients younger than 6 years of age and 66% involving male children. Food was the most common anaphylaxis trigger (74.7%), followed by drugs and radiocontrast media (10.7%), idiopathic factors (9.2%), and exercise (3.6%). The most common food allergen was milk (28.4%), followed by egg white (13.6%), walnut (8.0%), wheat (7.2%), buckwheat (6.5%), and peanut (6.2%). Milk and seafood were the most common anaphylaxis triggers in young and older children, respectively. Drug-triggered anaphylaxis was observed more frequently with increasing age, with antibiotics (34.9%) and nonsteroidal anti-inflammatory drugs (17.9%) being the most common causes. CONCLUSIONS: The most common anaphylaxis trigger in Korean children was food. Data on these triggers show that their relative frequency may vary by age.

Comparison between exhaled nitric oxide and bronchial challenge with methacholine or adenosine-5'-monophosphate in the diagnosis of childhood asthma

PURPOSE: Asthma is a chronic airway inflammatory disease characterized by bronchial hyperresponsiveness and reversible airway obstruction. Bronchial challenge with methacholine or adenosine-5'-monophosphate (AMP) has been used to diagnose asthma. Recently, measurement of exhaled nitric oxide (eNO) can also be used for the diagnosis of asthma. The aim of this study was to compare the diagnostic value for asthma between challenge with methacholine or AMP and eNO in children with chronic nonspecific respiratory symptoms. METHODS: One hundred thirty-three children who have chronic nonspecific respiratory symptoms were enrolled. Bronchial challenge with methacholin and AMP were performed, and eNO was measured in all subjects. Subjects were defined as asthma based on the clinical symptoms and bronchodilator response during follow-up of at least 3 months after test. RESULTS: Thirty-three subjects (34%) were finally diagnosed as asthma among 97 patients after 3-month follow-up. The area under the receiver operating characteristic curves for the diagnosis of asthma were 0.903 (95% confidence interval [CI], 0.838-0.969; P<0.001) for methacholline challenge, 0.867 (95% CI, 0.783-0.950; P<0.001) for AMP challenge, and 0.588 (95% CI, 0.467-0.709, P=0.156) for eNO measurement. The cutoff values of these tests were methacholine PC20 (provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second) 12.0 mg/mL (sensitivity, 87.9%; specificity, 82.8%), AMP PC20 566.2 mg/mL (sensitivity, 84.8%; specificity, 85.9%), and eNO 18.5 ppb (sensitivity, 45.5%; specificity, 71.9%). CONCLUSION: Measurement of eNO may be inferior to challenge with methacholine and AMP for the diagnosis of asthma in children.

Guideline for the prevention and management of particulate matter/yellow dust-induced adverse health effects on the patients with bronchial asthma

Particulate matter (PM) and specifically, Asian dust (or yellow dust), have been identified as critical causes of health problems. Recent increases in the levels of ambient PM are closely associated with adverse health effects in susceptible populations, such as the elderly, children, and patients with asthma or allergic disorders, and this is cause for recent concern in Korea. The establishment of strategies for the reduction of ambient PM by the government and industry, the development of practical guidelines and recommendations to protect susceptible individuals, and an action program for implementation in the general population, will be essential to minimize adverse health impacts of PM and yellow dust. However, guidelines for the proper prevention and management of PM/yellow dust-induced effects on asthma are unclear. In the present study, we aimed to develop evidence-based practice guidelines and recommendations for pediatric or adult patients with asthma and for general physicians who care for asthmatic patients, in order to provide protection from adverse health effects of PM exposure.