Developing a Diagnostic Bundle for Bronchiectasis in South Korea: A Modified Delphi Consensus Study / 결핵및호흡기질환

Background@#Because the etiologies of bronchiectasis and related diseases vary significantly among different regions and ethnicities, this study aimed to develop a diagnostic bundle for bronchiectasis in South Korea. @*Methods@#A modified Delphi method was used to develop expert consensus statements on a diagnostic bundle for bronchiectasis in South Korea. Initial statements proposed by a core panel, based on international bronchiectasis guidelines, were discussed in an online meeting and two email surveys by a panel of experts (≥70% agreement). @*Results@#The study involved 21 expert participants, and 30 statements regarding a diagnostic bundle for bronchiectasis were classified as recommended, conditional, or not recommended. The consensus statements of the expert panel were as follows: A standardized diagnostic bundle is useful in clinical practice; diagnostic tests for specific diseases, including immunodeficiency and allergic bronchopulmonary aspergillosis, are necessary when clinically suspected; initial diagnostic tests, including sputum microbiology and spirometry, are essential in all patients with bronchiectasis, and patients suspected with rare causes such as primary ciliary dyskinesia should be referred to specialized centers. @*Conclusion@#Based on this Delphi survey, expert consensus statements were generated including specific diagnostic, laboratory, microbiological, and pulmonary function tests required to manage patients with bronchiectasis in South Korea.

Coronavirus disease 2019 vaccines and relevant adverse reactions

In order to overcome the global pandemic of the new pathogen, severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), intensive research has been conducted to understand viral pathogenicity, establish effective treatment strategies, and develop vaccines against coronavirus disease 2019 (COVID-19). To prevent COVID-19, a variety of COVID-19 vaccines have been rapidly developed and are currently being administered worldwide. When developing new vaccines, monitoring for adverse events following immunization (AEFIs) has always been important, and some COVID-19 vaccines are particularly effective as new types of vaccines that have not been used before, thus attracting attention to AEFIs. Vaccine administration is carefully conducted while monitoring for AEFI that are being reported from time to time. AEFIs are largely divided into local reactions, systemic reactions, allergic reactions, and adverse reactions to specific diseases or disease- attributable events. In addition, it is classified according to causes, but it is very difficult to confirm the association with the vaccine. Anaphylaxis, which is a systemic reaction among serious allergic reactions, requires immediate treatment and may require testing to determine the cause. In order to increase the vaccination rate and secure herd immunity, there should be no fear of vaccination due to unidentified side effects. Therefore, monitoring of AEFIs is important and causal relationships must be well established based on reliable epidemiological investigations. Current data show that the benefits of a COVID-19 vaccine far outweigh the risk of AEFIs. Future studies should continue to understand the mechanisms and risk factors of identified adverse reactions.

Real-world treatment pattern of mycoplasma pneumonia in hospitalized children: A multicenter retrospective study

Purpose@#Macrolide-refractory Mycoplasma pneumoniae pneumonia (MP) has markedly increased since 2003 and corticosteroids or second-line antibiotics, such as fluoroquinolones or tetracyclines, was considered an alternative treatment modality in macrolide-refractory MP. We aimed to show the real-world treatment pattern of MP in hospitalized children and compared clinical and laboratory findings between children with and without steroid treatment. @*Methods@#We reviewed the medical records of 384 children diagnosed with MP from 6 hospitals in Korea from August 2015 to March 2016. We investigated the clinical, laboratory and radiologic findings, and medications used for the treatment of the subjects. @*Results@#The corticosteroids and second-line antibiotics were administered in 55.5% and 7.0%, respectively. The percentages of steroid administration varied from 17% to 69% in each hospital. The mean start date of corticosteroid administration was 3.4 hospital days. Patients with corticosteroid treatment had a longer length of hospital stay than those without corticosteroid. They exhibited higher rates of lobar pneumonia and pleural effusion, and required longer days until improvement in chest X-ray findings. They also had higher rates of allergic diseases and showed higher C-reactive protein levels at admission. @*Conclusion@#In the real-world practice studied in the 6 hospitals, corticosteroids were more frequently administered than second-line antibiotics to hospitalized children with MP. Children with corticosteroid adjuvant therapy had more severe pneumonia than those without. Randomized controlled trials are needed to make appropriate guidelines for macrolide-refractory MP.

Effect of high flow nasal cannula treatment in children with respiratory distress at the general ward

Purpose@#This study evaluated the clinical effects of heated humidified high flow nasal cannula (HHHFNC) treatment in pediatric patients with respiratory disease and respiratory insufficiency. @*Methods@#We reviewed the medical records for clinical features and tests performed in patients admitted to Chungnam University Hospital pediatric ward and treated with HHHFNC between July 2014 and December 2018. We evaluated the effects of HHHFNC treatment in patients with bronchiolitis treated with oxygen using a nasal prong. @*Results@#The 136 children were treated with HHHFNC during the study period, and their median age was 8 months. Among the 136 patients, 39 (28.7%) were diagnosed with bronchiolitis and pneumonia, 42 (30.9%) with pneumonia, 28 (20.6%) with bronchiolitis, and 3 (2.2%) with epilepsy. Thirty-five patients (25.7%) had underlying neurological disorders. Fifty-one (37.5%) received invasive ventilator treatment. After HHHFNC treatment, venous blood gas analysis showed a pH increase from 7.32 to 7.37 (P<0.05) and a decrease in partial pressure of carbon dioxide (pCO2) from 53.1 to 46.2 mmHg (P<0.05). The respiratory rate had decreased from 46.3 to 43.3/min (P<0.05). There were no statistically significant differences in hospital stay duration or intensive care unit admission rates between bronchiolitis patients receiving HHHFNC treatment and those not receiving. @*Conclusion@#In this study, in various diseases leading to pediatric respiratory insufficiency, HHHFNC treatment may improve physiologic parameters at the pediatric ward. HHHFNC may also be effective in patients with underlying neurological disorders and those with respiratory insufficiency from nonrespiratory infectious disease.

Investigation of adverse events following bacille CalmetteGuérin immunization using immunization safety surveillance system in Korea Centers for Disease Control and Prevention

Purpose@#The report of adverse events following immunization (AEFI) in Korea has continued since 1994, and the most frequently reported cases of AEFI of Korea Centers for Disease Control and Prevention (KCDC) is bacille Calmette-Guérin (BCG). Meanwhile, various inoculation methods and strains have been used in the past 6 years in Korea. Therefore, we investigated AEFI of BCG by strain types and inoculation methods using immunization safety surveillance of KCDC. @*Materials and Methods@#We reviewed BCG AEFIs registered in the KCDC from January 2013 to June 2018. @*Results@#There were 336 AEFI cases during the period, and average time interval from vaccination to symptom onset was within 2 months. AEFI proportion was 6.4 cases per 100,000 doses for BCG percutaneous Tokyo strain, 41.6 cases per 100,000 doses of BCG intradermal Danish strain, and 25.9 cases per 100,000 doses of BCG intradermal Tokyo strain. Intradermal type was more reported AEFI than percutaneous type in the same strain. The most common adverse events were local reaction like BCG lymphadenitis and severe adverse reactions such as osteomyelitis or disseminated BCG disease were 0.1 to 0.2 cases per 100,000 doses which are correlated with the range of World Health Organization published AEFI rates. @*Conclusion@#The AEFI reporting rate does not equal the actual proportion of AEFI occurrence. Because AEFI monitoring is a passive surveillance system, various factors might influence the number of events reported. Nevertheless, it is important to analyze BCG AEFI by vaccine strains and inoculation method using surveillance data of KCDC.

Investigation of adverse events following bacille CalmetteGuérin immunization using immunization safety surveillance system in Korea Centers for Disease Control and Prevention

Purpose@#The report of adverse events following immunization (AEFI) in Korea has continued since 1994, and the most frequently reported cases of AEFI of Korea Centers for Disease Control and Prevention (KCDC) is bacille Calmette-Guérin (BCG). Meanwhile, various inoculation methods and strains have been used in the past 6 years in Korea. Therefore, we investigated AEFI of BCG by strain types and inoculation methods using immunization safety surveillance of KCDC. @*Materials and Methods@#We reviewed BCG AEFIs registered in the KCDC from January 2013 to June 2018. @*Results@#There were 336 AEFI cases during the period, and average time interval from vaccination to symptom onset was within 2 months. AEFI proportion was 6.4 cases per 100,000 doses for BCG percutaneous Tokyo strain, 41.6 cases per 100,000 doses of BCG intradermal Danish strain, and 25.9 cases per 100,000 doses of BCG intradermal Tokyo strain. Intradermal type was more reported AEFI than percutaneous type in the same strain. The most common adverse events were local reaction like BCG lymphadenitis and severe adverse reactions such as osteomyelitis or disseminated BCG disease were 0.1 to 0.2 cases per 100,000 doses which are correlated with the range of World Health Organization published AEFI rates. @*Conclusion@#The AEFI reporting rate does not equal the actual proportion of AEFI occurrence. Because AEFI monitoring is a passive surveillance system, various factors might influence the number of events reported. Nevertheless, it is important to analyze BCG AEFI by vaccine strains and inoculation method using surveillance data of KCDC.

Vaccine-related Anaphylaxis Cases Confirmed by KCDC from 2001–2016

Background@#A national immunization program (NIP) to prevent disease and reduce mortality from vaccine preventable diseases (VPD) is very important. @*Methods@#We analyzed only the anaphylaxis cases that occurred between 2001 and 2016 that Korea Centers for Disease Control and Prevention (KCDC) determined had a definite causal relationship with a vaccine. The clinical symptoms were assessed according to the Brighton Collaboration case definition (BCCD) level. @*Results@#During the period, there were 13 cases of vaccine-related anaphylaxis. The median age was 9 years (range, 1 month to 59 years). The incidence of anaphylaxis per million doses was 0.090 in 2005, 0.079 in 2012, 0.071 in 2013, 0.188 in 2015, and 0.036 in 2016. Of those cases, 23.1% were influenza vaccines, and 76.9% were BCCD level 2. Epinephrine was used in 46.2%. @*Conclusion@#Vaccine-related anaphylaxis seems to have been very rare in the past, but health care professionals must always be aware of anaphylaxis.

A Child of Severe Mycoplasma pneumoniae pneumonia with Multiple Organ Failure Treated with ECMO and CRRT

Mycoplasma pneumoniae (MP) is the most common causative agent of community-acquired pneumonia in school-aged children. An 8-year-old boy who had been diagnosed with autism looked severely ill when he presented to our hospital due to dyspnea and lethargy. He had fever and cough 7 days prior to hospitalization. He had signs and symptoms of severe respiratory distress. The percutaneous oxygen saturation was 88% at high oxygen supply. Chest radiography showed diffusely increased opacity with moderate pleural effusion. He was intubated immediately and admitted to the intensive care unit. Under the clinical impression of mycoplasmal pneumonia, intravenous clarithromycin was started. Laboratory findings showed leukocytosis, hepatitis, decreased renal function, and presence of serum MP immunoglobulin (Ig) M (+) IgG (+) and sputum MP polymerase chain reaction (+). On hospital day 2, the patient developed multiple organ failure with acute respiratory distress syndrome (ARDS). Veno-venous extracorporeal membrane oxygenation (ECMO) was performed with continuous renal replacement therapy (CRRT) and was weaned successfully. This is the first reported case of an ARDS due to MP infection complicated by multiple organ failure that was successfully treated with ECMO and CRRT in South Korea.

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.

The changes of prevalence and etiology of pediatric pneumonia from National Emergency Department Information System in Korea, between 2007 and 2014 / 소아과

PURPOSE: Understanding changes in pathogen and pneumonia prevalence among pediatric pneumonia patients is important for the prevention of infectious diseases. METHODS: We retrospectively analyzed data of children younger than 18 years diagnosed with pneumonia at 117 Emergency Departments in Korea between 2007 and 2014. RESULTS: Over the study period, 329,380 pediatric cases of pneumonia were identified. The most frequent age group was 1–3 years old (48.6%) and the next was less than 12 months of age (17.4%). Based on International Classification of Diseases, 10th revision diagnostic codes, confirmed cases of viral pneumonia comprised 8.4% of all cases, pneumonia due to Mycoplasma pneumoniae comprised 3.8% and confirmed cases of bacterial pneumonia 1.3%. The prevalence of confirmed bacterial pneumonia decreased from 3.07% in 2007 and 4.01% in 2008 to 0.65% in 2014. The yearly rate of pneumococcal pneumonia also decreased from 0.47% in 2007 to 0.08% in 2014. A periodic prevalence of M. pneumoniae pneumonia (MP) was identified. CONCLUSION: The increased number of patients with pneumonia, bacterial pneumonia, pleural effusion, and empyema in 2011 and 2013–2014 resulted from an MP epidemic. We provide evidence that the frequency of confirmed cases of bacterial pneumonia and pneumococcal pneumonia has declined from 2007 to 2014, which can simultaneously reflect the effectiveness of the pneumococcal conjugate vaccine.

Internalizing Symptoms as Mediators of Lifetime Incidence of Trauma and Quality of Life among Out-of-School Youths

OBJECTIVES: The present study aimed to investigate the relationships among the lifetime incidence of trauma, internalizing symptoms, and quality of life (QoL) in out-of-school youths (OSYs). METHODS: We recruited 50 OSYs in South Korea. Participants completed the following surveys: completed Lifetime Incidence of Traumatic Events for children, Youth Self Report, and The KIDSCREEN-27 QoL measure for children and adolescents. Mediation analysis was conducted to test the research hypotheses. RESULTS: The mean lifetime incidence of traumatic events among OSYs was 3.27 (standard deviation, 2.41). Internalizing symptoms significantly mediated the lifetime incidence of trauma and QoL. OSYs with fewer internalizing symptoms exhibited a better QoL in the domain of psychological well-being, although their lifetime incidence of trauma was higher. CONCLUSION: The results of current study suggest that assessment and therapeutic intervention with regard to internalizing symptoms are needed to increase the QoL of OSYs.

Seasonal Patterns of Asthma in Children and Adolescents Presenting at Emergency Departments in Korea

PURPOSE: Seasonal variations in asthma-related hospitalizations and emergency department visits have long been recognized. This study aimed to investigate the seasonal patterns of asthma in children and adolescents who presented at emergency departments in Korea. METHODS: We analyzed the National Emergency Department Information System records from 117 emergency departments in Korea that comprised all of the patients with asthma who were aged 3-18 years and who presented at the emergency departments from 2007 to 2012. The children and adolescents were divided into 3 groups based on their ages, namely, 3-6 years, 7-12 years, and 13-18 years. The data were tabulated, and graphs were created to show the seasonal trends in the monthly numbers of emergency department visits as a consequence of asthma. RESULTS: A total of 41,128 subjects were identified, and the male-to-female ratio was 1:0.5. General ward admissions comprised 42.6% (n=17,524 patients) of the emergency department visits, and intensive care unit admissions comprised 0.8% (n=335 patients) of the emergency department visits. The monthly numbers of emergency department visits for asthma varied according to the season, with high peaks during fall, which was from September to November, and low levels in summer, which was from June to August. CONCLUSIONS: Important differences in the seasonal patterns of emergency department visits for asthma were evident in children and adolescents. Identifying seasonal trends in asthma-related emergency department visits may help determine the causes and reduce the likelihood of asthma exacerbation.

Clinical implication of adverse drug reaction surveillance in children

No abstract available.

A nationwide study of children and adolescents with pneumonia who visited Emergency Department in South Korea in 2012 / 소아과

PURPOSE: Acute respiratory infection, particularly pneumonia, is the most common cause of hospitalization and death among children in developing nations. This study aimed to investigate the characteristics of children and adolescents with pneumonia who visited Emergency Department (ED) in South Korea in 2012. METHODS: We analyzed National Emergency Department Information System (NEDIS) records from 146 EDs in South Korea for all pediatric patients aged ≤18 years who were diagnosed with pneumonia between January and December 2012. RESULTS: Among 38,415 subjects, the male-to-female ratio was 1:0.8. Patients aged <12 months comprised 18.0% of the study population; those aged 1 to 3 years, 54.4%; those aged 4 to 6 years, 16.8%; those aged 7 to 12 years, 7.4%; and those aged 13 to 18 years, 3.4%. Presentation rates were highest in April, followed by January, March, and May. The hospital admission rate was 43.5%, of which 2.6% were in intensive care units. The mortality rate was 0.02%. Based on the International Classification of Diseases, 10th Revision, diagnostic codes, the types of pneumonia according to cause were viral pneumonia (29.0%), bacterial pneumonia (5.3%), Mycoplasmal pneumonia (4.5%), aspiration pneumonia (1.3%), and pneumonia of unknown origin (59.3%). CONCLUSION: Despite the limited data due to the ED data from the NEDIS lacking laboratory results and treatment information, this study reflects well the outbreak patterns among children and adolescents with pneumonia. Our results provide a basis for future studies regarding ED treatment for children and adolescents with pneumonia.

A nationwide study of children and adolescents with pneumonia who visited Emergency Department in South Korea in 2012 / 소아과

PURPOSE: Acute respiratory infection, particularly pneumonia, is the most common cause of hospitalization and death among children in developing nations. This study aimed to investigate the characteristics of children and adolescents with pneumonia who visited Emergency Department (ED) in South Korea in 2012. METHODS: We analyzed National Emergency Department Information System (NEDIS) records from 146 EDs in South Korea for all pediatric patients aged ≤18 years who were diagnosed with pneumonia between January and December 2012. RESULTS: Among 38,415 subjects, the male-to-female ratio was 1:0.8. Patients aged <12 months comprised 18.0% of the study population; those aged 1 to 3 years, 54.4%; those aged 4 to 6 years, 16.8%; those aged 7 to 12 years, 7.4%; and those aged 13 to 18 years, 3.4%. Presentation rates were highest in April, followed by January, March, and May. The hospital admission rate was 43.5%, of which 2.6% were in intensive care units. The mortality rate was 0.02%. Based on the International Classification of Diseases, 10th Revision, diagnostic codes, the types of pneumonia according to cause were viral pneumonia (29.0%), bacterial pneumonia (5.3%), Mycoplasmal pneumonia (4.5%), aspiration pneumonia (1.3%), and pneumonia of unknown origin (59.3%). CONCLUSION: Despite the limited data due to the ED data from the NEDIS lacking laboratory results and treatment information, this study reflects well the outbreak patterns among children and adolescents with pneumonia. Our results provide a basis for future studies regarding ED treatment for children and adolescents with pneumonia.

Clinical characteristics of children and adolescents with croup and epiglottitis who visited 146 Emergency Departments in Korea / 소아과

PURPOSE: Croup is a common pediatric respiratory illness with symptoms of varying severity. Moreover, epiglottitis is a rare disease that can rapidly progress to life-threatening airway obstruction. Although the clinical course and treatments differ between croup and epiglottitis, they are difficult to differentiate on presentation. We aimed to compare the clinical characteristics of croup and epiglottitis in Emergency Department patients. METHODS: The 2012 National Emergency Department Information System database of 146 Korean Emergency Departments was used to investigate patients aged < or =18 years presenting with croup or epiglottitis. RESULTS: We analyzed 19,374 croup patients and 236 epiglottitis patients. The male:female sex ratios were 1.9:1 and 2.3:1 and mean ages were 2.2+/-2.0 and 5.6+/-5.8 years, respectively. The peak incidence of croup was observed in July and that of epiglottitis was observed in May. The hospitalization rate was lower in croup than in epiglottitis patients, and the proportion of patients treated in the intensive care unit was lower among croup patients. The 3 most common chief complaints in both croup and epiglottitis patients were cough, fever, and dyspnea. Epiglottitis patients experienced dyspnea, sore throat, and vomiting more often than croup patients (P<0.05). CONCLUSION: Both groups had similar sex ratios, arrival times, 3 most common chief complaints, and 5 most common comorbidities. Epiglottitis patients had a lower incidence rate, higher mean age of onset, and higher hospitalization rate and experienced dyspnea, sore throat, and vomiting more often than croup patients. Our results may help in the differential diagnosis of croup and epiglottitis.

Clinical characteristics of patients with acute bronchiolitis who visited 146 Emergency Department in Korea in 2012

PURPOSE: This study was aimed to investigate the clinical and epidemiological characteristics of the patients with acute bronchiolitis who visited in 146 Emergency Departments (EDs) in Korea in 2012. METHODS: We used the NEDIS (National Emergency Department Information System) database to obtain all children with acute bronchiolitis who visited ED under the age of 3 between January 1, 2012 and December 31, 2012. RESULTS: Totally 18,313 children with acute bronchiolitis were enrolled at this study. The male to female ratio was 1.55:1 and mean age was 10 months. The peak proportion was 17.3% in November during the whole year. The most common chief complaints were fever (38.5%), cough (37.4%), dyspnea (9.5%), gastrointestinal symptom (6.7%), and wheezing (2.5%). The most common accompanying disease was pneumonia (13.3%). The rate of hospital admission and intensive care unit admission were 34.5% and 0.3%, respectively. A predictor for admission via ED was respiratory difficulty. CONCLUSION: These data expand our understanding of clinical characteristics of patients with acute bronchiolitis who visited all ED in Korea in 2012.

Vaccine allergies

Currently, the increasing numbers of vaccine administrations are associated with increased reports of adverse vaccine reactions. Whilst the general adverse reactions including allergic reactions caused by the vaccine itself or the vaccine components, are rare, they can in some circumstances be serious and even fatal. In accordance with many IgE-mediated reactions and immediate-type allergic reactions, the primary allergens are proteins. The proteins most often implicated in vaccine allergies are egg and gelatin, with perhaps rare reactions to yeast or latex. Numerous studies have demonstrated that the injectable influenza vaccine can be safely administered, although with appropriate precautions, to patients with severe egg allergy, as the current influenza vaccines contain small trace amounts of egg protein. If an allergy is suspected, an accurate examination followed by algorithms is vital for correct diagnosis, treatment and decision regarding re-vaccination in patients with immediate-type reactions to vaccines. Facilities and health care professionals should be available to treat immediate hypersensitivity reactions (anaphylaxis) in all settings where vaccines are administered.

Clinical characteristics of respiratory virus infection in children admitted to an intensive care unit

PURPOSE: To investigate the clinical characteristics and the risk factors for mechanical ventilator treatment and incidence of complications in children admitted to an intensive care unit (ICU) with detected respiratory viruses. METHODS: Eighty-two patients who were detected respiratory viruses by multiplex real-time polymerase chain reaction from nasopharyngeal aspirates were enrolled among the 123 children admitted to ICU with acute respiratory manifestations during the study period from January 2006 to December 2012. RESULTS: Detection rate of respiratory viruses were 66% and 13 patients (16%) had two viruses isolated. The most common respiratory virus isolated was respiratory syncytial virus (RSV) (35%) followed by rhinovirus (19%), adenovirus (13%), parainfluenza virus (11%), influenza virus (11%), human metapneumovirus (6%), and human coronavirus (5%). Pneumonia (70%) was the most common clinical diagnosis. The mean age of patient with RSV infection was the youngest and with influenza virus infection was the oldest among other viruses infection (mean+/-standard deviation, 5.9+/-10.1 months vs. 51.0+/-26.1 months; P=0.01). Forty Patients (49%) who had the underlying diseases were not associated with incidence of mechanical ventilator treatment and complications. Bacterial coinfection with respiratory virus was the significant risk factor of mechanical ventilator care and incidence of complications (odds ratio [OR], 50.003; 95% confidence interval [CI], 3.955-632.144; P=0.003, and OR, 15,569; 95% CI, 1.803-134.452; P=0.013). CONCLUSION: The significant morbidity of pediatric patient admitted to ICU with respiratory virus infection (RVI) was associated with bacterial coinfection. Furthermore, multicenter study should be performed to investigate the epidemiology of RVI in pediatric patients admitted to ICU in domestic.

Prevalence of Primary Immunodeficiency in Korea

This study represents the first epidemiological study based on the national registry of primary immunodeficiencies (PID) in Korea. Patient data were collected from 23 major hospitals. A total of 152 patients with PID (under 19 yr of age), who were observed from 2001 to 2005, have been entered in this registry. The period prevalence of PID in Korea in 2005 is 11.25 per million children. The following frequencies were found: antibody deficiencies, 53.3% (n = 81), phagocytic disorders, 28.9% (n = 44); combined immunodeficiencies, 13.2% (n = 20); and T cell deficiencies, 4.6% (n = 7). Congenital agammaglobulinemia (n = 21) and selective IgA deficiency (n = 21) were the most frequently reported antibody deficiency. Other reported deficiencies were common variable immunodeficiencies (n = 16), X-linked agammaglobulinemia (n = 15), IgG subclass deficiency (n = 4). Phagocytic disorder was mostly chronic granulomatous disease. A small number of patients with Wiskott-Aldrich syndrome, hyper-IgE syndrome, and severe combined immunodeficiency were also registered. Overall, the most common first manifestation was pneumonia. This study provides data that permit a more accurate estimation PID patients in Korea.