Most treatment strategies for asthma currently include inhaled corticosteroids, with the addition of long-acting beta-2-agonists or leukotriene modifiers, if necessary. However, some patients may not respond to conventional treatment. A better understanding of the pathophysiology of asthma has recently led to the development of biological agents, which have shown promising results for symptom control and future risk reduction in severe asthmatics. This article reviews currently available biologic agents, introduces related studies, and describes the subgroup of patients benefitting from each of biologic agents in the view point of precision medicine. (Allergy Asthma Respir Dis 2019;7:3-12)

Purpose: Wet wrap therapy is a well-known treatment for severe atopic dermatitis (AD). However, wet wrap therapy with usual bandage was a troublesome and time-consuming process of application. The aim of this study was to evaluate the efficacy, safety and convenience of wet wrap therapy with new garments in children with moderate-to-severe AD.
Methods: We compared 56 AD children treated with wet wrap therapy and 14 AD children treated with only conventional therapy. We retrospectively reviewed the clinical features, change of SCORing Atopic Dermatitis (SCORAD) index, adverse effects and parent's reports.
Results: The initial mean SCORAD index was 60.3±15.3 points. No significant differences in sex, age, initial SCORAD index, total eosinophil count, total IgE level, food allergen sensitization, inhalant allergen sensitization or associated allergic diseases were found between the wet wrap and conventional groups. The pharmacological and nonpharmacological interventions except wet wrap therapy were same in the 2 groups. Wet wrap therapy with garments or tubular bandage was easily done one time per day overnight in 10.6±3.5 days by parents. Improvement in total SCORAD index, intensity, subjective symptoms and pruritus were significantly higher in the wet wrap group than in the conventional group (36.2 vs. 26.9, 6.0 vs. 4.0, 9.9 vs. 7.4, and 4.8 vs. 3.6 points). No folliculitis and serious adverse effects were reported.
Conclusion: Wet wrap therapy with new garments could be easily done by parents. Wet wrap therapy may be effective and safe in controlling moderate-to-severe AD in children. (Allergy Asthma Respir Dis 2019;7:13-21)

Purpose: The aim of this study was to compare the clinical usefulness of serum procalcitonin (PCT) levels in Mycoplasma pneumoniae pneumonia (M. pneumonia) and viral pneumonia in children.
Methods: We retrospectively analyzed the medical records of 348 patients admitted between June 2015 and December of 2015. There were 162 patients with M. pneumonia without virus coinfection (group 1) and 186 patients with viral pneumonia (group 2). All subjects had radiographic evidence of pneumonia with available specimens for both M. pneumonia and viral testing, and levels of serum PCT, white blood cell counts (WBC), neutrophil portion, and C-reactive protein (CRP). Fifty-eight children who performed follow-up sampling at the time of no fever for more than 48 hours were subdivided into group 3 (M. pneumonia with follow-up sampling, n=41) and group 4 (viral pneumonia with follow-up sampling, n=17).
Results: No difference was noted in the levels of serum PCT (P=0.168), CRP (P=0.296), WBC (P=0.732), and neutrophil proportion (P=0.069) between groups 1 and 2, after adjusting for age. Serial changes in serum PCT levels between the first and second samples were significant in group 3 (P=0.046). Serial changes in serum CRP levels between the first and second samples were significant in group 4 (P=0.008).
Conclusion: Serum PCT and CRP levels may change differently after infection according to the etiology of pneumonia. (Allergy Asthma Respir Dis 2019;7:22-27)

Purpose: Croup is a common respiratory disease in children. The aim of this study was to analyze the epidemiology, etiology, and seasonal variations of respiratory virus infections in children with croup.
Methods: From October 2009 to September 2017, children admitted with croup to Gachon University Gil Medical Center under the age of 18 years were enrolled in this study. We retrospectively reviewed patients' medical records.
Results: A total of 1,053 of 27,330 patients (3.9%) infected with lower respiratory infections were diagnosed as having croup. In the age distribution, croup was most common (50.0%) in children aged 1 to <2 years. There were 2 peaks, the major in summer (July to August) and the minor in spring (March to May). Parainfluenza virus type 1 (15.8%) was most prevalent and coincided with the summer peaks of croup. Influenza virus type B and parainfluenza virus type 3 were the most frequent etiologic agents in a spring peak of croup. Although parainfluenza virus type 1 was predominant of all ages, human coronavirus was a significant cause of croup in children younger than 1 year, whereas influenza virus played an important role in children above the age of 3 years.
Conclusion: Seasonality and epidemiology of croup varied with age and regions. Two peaks of seasonal fluctuation were in summer and spring, which were related to the seasonality of respiratory viruses in croup. These results may be helpful in planning clinical and research needs. (Allergy Asthma Respir Dis 2019;7:28-36)

Purpose: Several studies have reported an association between lead exposure and increased risk of allergic sensitization and asthma. According to the Centers for Disease Control and Prevention guidelines, An elevated blood lead level (BLL) is defined as a BLL of ≥5 μg/dL. However, no safe BLL has been identified, and it is controversial whether a BLL of <5 μg/dL affects the risk of asthma.
Methods: We examined asthma prevalences and BLLs using data from the 2010-2013 Korea National Health and Nutrition Examination Survey (KNHANES), which was a cross-sectional survey of 1,478 adolescence (aged 10-19 years) throughout the country. The adjusted odds ratios (ORs) (with 95% confidence intervals [CIs]) for the prevalence of asthma in adolescence with elevated BLLs were calculated by complex samples multivariate logistic regression analysis. The presence of asthma was based on self-reported, physician-diagnosed asthma in the Health Interview Surveys.
Results: The mean of total BLLs was 1.33 μg/dL. Overall, 5.1% (n=71) of the subjects were physician diagnosed asthma. In the model controlling for population characteristics, the adjusted odds ratio for asthma per 1 μg/dL increase in blood lead was 1.94, 95% CI (1.06, 3.57), and stronger associations were observed among boys (adjusted OR, 2.31; 95% CI, [1.18, 4.51]). The group of BLL≥2 μg/dL was associated with an OR of 2.84 (95% CI, 1.06, 7.63) for asthma, after adjusting for potential confounding factors in boys.
Conclusion: Our results suggest an association between total BLLs and asthma in Korean adolescent boys, although confirmation is warranted in further prospective studies. (Allergy Asthma Respir Dis 2019;7:37-43)

Purpose: Despite improved quality of intensive care, acute respiratory distress syndrome (ARDS) significantly contributes to mortality in critically ill children. As pre-existing definitions of ARDS were adult-oriented standards, the Pediatric Acute Lung Injury Consensus Conference (PALICC) group released a new definition of pediatric ARDS. In this study, we aimed to assess the performance of PALICC definition for ARDS risk stratification.
Methods: Total 332 patients who admitted to the intensive care unit at Severance Hospital from January 2009 to December 2016 and diagnosed as having ARDS by either the PALICC definition or the Berlin definition were retrospectively analyzed. Patient characteristics and mortality rates were compared between the individual severity groups according to both definitions.
Results: The overall mortality rate was 36.1%. The mortality rate increased across the severity classes according to both definitions (26% in mild, 37% in moderate and 68% in severe by the PALICC definition [P<0.001]; 20% in mild, 32% in moderate and 64% in severe by the Berlin definition [P<0.001]). The mortality risk increased only for severe ARDS in both definitions (hazard ratio [95% confidence interval]: 2.279 [1.414-3.672], P=0.001 by the PALICC definition; 2.674 [1.518-4.712], P=0.001 by the Berlin definition). There was no significant difference in mortality discrimination between the 2 definitions (difference in integrated area under the curve: 0.017 [-0.018 to 0.049]).
Conclusion: The PALICC definition demonstrated similar discrimination power on PARDS' severity and mortality as the Berlin definition. (Allergy Asthma Respir Dis 2019;7:44-50)

Purpose: Noninvasive positive pressure ventilation (NIPPV) is one of the ventilation-supporting methods by providing adequate exogenous pressure without intubation or tracheostomy. We aimed to assess the frequency and clinical factors for pneumothorax occurring during NIPPV application in a tertiary children's hospital.
Methods: We selected cases of pneumothorax related to NIPPV by keyword searching in our institution's clinical data warehouse, and their medical records were retrospectively reviewed.
Results: During a period of 17 years, 15 cases undergoing NIPPV developed pneumothorax, which was an incidence of 0.64% (15 of 2,343). There were 9 neonates and 6 adolescents. In 9 neonates, pneumothorax was caused by the continuous positive airway pressure (CPAP) ventilator, and occurred on 2 days after birth (median, range 1-3 days). In neonates, pneumothorax developed within 36 hours after CPAP application. One neonate underwent tracheal intubation and 3 neonates underwent chest tube insertion. In the postteenager group, pneumothorax developed 23 months (median, range 5 days to 47 months) after NIPPV application with a mask. All of the 6 patients had underlying neuromuscular disorders and one had superimposed interstitial lung disease. One of the 7 cases underwent surgical treatment and 4 cases were intubated. One case died from the deterioration of underlying interstitial lung disease.
Conclusion: Although it rarely happens, the NIPPV can result in pneumothorax. In most cases, it can be resolved by supportive cares with oxygen or chest tube with or without tracheostomy. The prognosis is related to the type of underlying disease and its progression. (Allergy Asthma Respir Dis 2019;7:51-56)

Exogenous lipoid pneumonia is an uncommon medical condition resulting from aspiration or inhalation of oily material. Generally, lipoid pneumonia has nonspecific clinical and radiological presentations, and may be misdiagnosed as bacterial pneumonia or lung cancer. We describe an unusual case of exogenous lipoid pneumonia accompanied by peripheral blood and pulmonary eosinophilia. A 63-year-old man was admitted with progressively worsening exertional dyspnea and productive cough for 5 days. A chest radiograph showed abnormalities in the lower lobe of the right lung, and a diagnosis of community-acquired pneumonia was made; intravenous antibiotics were administered. However, dyspnea and hypoxia gradually worsened and peripheral blood eosinophilia developed. A bronchoscopy was performed and bronchoalveolar lavage fluid analysis showed markedly increased numbers of eosinophils (40%). Subsequently, a comprehensive review of history revealed that he fell asleep with camellia oil in his mouth for 2 weeks to relieve foreign body sensation of the throat. Sputum and bronchoalveolar lavage fluid cytology showed the presence of lipid-laden macrophages. He was diagnosed with lipoid pneumonia and acute eosinophilic pneumonia. Chest radiograph and symptom were rapidly improved after treatment with intravenous methylprednisolone. (Allergy Asthma Respir Dis 2019;7:57-60)

Propionibacterium acnes is one of the commensals living on the human skin and glands, implicated mainly in acnes, but seldom in deep infection. Pleural empyema is rarely complicated with closed thoracostomy. We experienced 1 case of empyema caused by P. acnes after pleural biopsy and closed thoracostomy through a percutaneous pigtail catheter. A 79-year-old man was admitted for cough, purulent sputum and shortness of breath. Three weeks ago, closed thoracostomy and pleural biopsy were performed to confirm a diagnosis for his recurrent pleural effusion. He had increased amount of right pleural effusion. Through the pigtail catheter, pleural effusion was removed. Gram-positive rods were observed in Gram stain, but not cultured. By 16S rRNA analysis, P. acnes was confirmed as the pathogen. His empyema was repeatedly treated with antibiotics, fibrolysis and irrigation. Pleural decortication was recommended. We report the first case of empyema with P. acnes in Korea, possibly complicated with closed thoracostomy procedures. (Allergy Asthma Respir Dis 2019;7:61-64)