Asthma comprises a heterogeneous group of disorders characterized by airway inflammation, airway obstruction, and airway hyperresponsiveness (AHR). Airway inflammation, which induces AHR and recurrence of asthma, is the main pathophysiology of asthma. The fractional exhaled nitric oxide (FeNO) level is a noninvasive, reproducible measurement of eosinophilic airway inflammation that is easy to perform in young children. As airway inflammation precedes...

Atopic sensitization is a complex phenomenon that changes dynamically with age throughout childhood; its prevalence increases with age in young children. Additionally, with increasing age, the prevalence of sensitization to inhalant allergens and the prevalence of polysensitization to allergens increase. It is also well established that the development of atopic sensitization is the result of a complex interplay of genetic...

Influenza causes acute respiratory infections and various complications. Children in the high-risk group have higher complication and hospitalization rates than high-risk elderly individuals. Influenza prevention in children is important, as they can be a source infection spread in their communities. Influenza vaccination is strongly recommended for high-risk children with chronic underlying circulatory and respiratory disease, immature infants, and children receiving...

Respiratory distress syndrome (RDS) among preterm infants is typically due to a quantitative deficiency of pulmonary surfactant. Aside from the degree of prematurity, diverse environmental and genetic factors can affect the development of RDS. The variance of the risk of RDS in various races/ethnicities or monozygotic/dizygotic twins has suggested genetic influences on this disorder. So far, several specific mutations in...

Cord blood (CB) has been used as an important and ethical source for hematopoietic stem cell transplantation (SCT) as well as cell therapy by manufacturing mesenchymal stem cell, induced pleuripotential stem cell or just isolating mononuclear cell from CB. Recently, the application of cell-based therapy using CB has expanded its clinical utility, particularly, by using autologous CB in children with...

The use of glucocorticoids (GCs) in the perinatal period is suspected of being associated with adverse effects on long-term neurodevelopmental outcomes for preterm infants. Repeated administration of antenatal GCs to mothers at risk of preterm birth may adversely affect fetal growth and head circumference. Fetal exposure to excess GCs during critical periods of brain development may profoundly modify the limbic...

Pediatric infection with Helicobacter pylori may occur early in childhood and persist lifelong. Global pediatric clinical studies have reported a decreasing tendency in the overall rate of H. pylori eradication. In pediatric patients with H. pylori infection, pediatric patients with peptic ulcer, and the first-degree relatives of patients with a history of gastric cancer, it is commonly recommended that H....

The 7-valent pneumococcal protein conjugate vaccine (PCV7) has been shown to be highly efficacious against invasive pneumococcal diseases and effective against pneumonia and in reducing otitis media. The introduction of PCV7 has resulted in major changes in the epidemiology of pneumococcal diseases. However, pneumococcal vaccines induce serotype-specific immunity, and a relative increase in non-vaccine serotypes has been reported following the...

Recently, surgical outcomes of repair of tetralogy of Fallot (TOF) have improved. For patients with TOF older than 3 months, primary repair has been advocated regardless of symptoms. However, a surgical approach to symptomatic TOF in neonates or very young infants remains elusive. Traditionally, there have been two surgical options for these patients: primary repair versus an initial aortopulmonary shunt...

Channelopathies are a heterogeneous group of disorders resulting from the dysfunction of ion channels located in the membranes of all cells and many cellular organelles. These include diseases of the nervous system (e.g., generalized epilepsy with febrile seizures plus, familial hemiplegic migraine, episodic ataxia, and hyperkalemic and hypokalemic periodic paralysis), the cardiovascular system (e.g., long QT syndrome, short QT syndrome,...

Timely diagnosis of hyponatremia is important for preventing potential morbidity and mortality as it is often an indicator of underlying disease. The most common cause of eurvolemic hyponatremia is the syndrome of inappropriate antidiuretic hormone (SIADH) secretion. Recent studies have demonstrated that proinflammatory cytokines such as interleukin (IL) 1β and IL-6 are involved in the development of hyponatremia, a condition...

The etiology of small and fresh rectal bleeding in neonates who are not sick is usually unknown; the only known cause is food protein-induced proctocolitis (FPIPC). It has been recently reported that FPIPC is a rare cause of rectal bleeding in newborns, and most cases have been proved to be due to idiopathic neonatal transient colitis. A recommended strategy for...

Because the prevalence of allergic diseases has significantly increased in recent years, understanding the causes and mechanisms of these disorders is of high importance, and intense investigations are ongoing. Current knowledge pinpoints immune tolerance mechanisms as indispensable for healthy immune response to allergens in daily life. It is evident that development and maintenance of allergens-pecific T cell tolerance is of...

The epidemiology of human group A rotavirus was analyzed by examining genotypic data acquired from 1989 to 2009 in South Korea. This information was derived from all the available published articles on rotavirus studies in South Korea, retrieved from both the PubMed and KoreaMed databases. Four common G types (G1, G2, G3, and G4) and three common P types (P[8],...

Improving mental health and reducing the burden of mental illness are complementary strategies which, along with the treatment and rehabilitation of people with mental disorders, significantly improve population health and well-being. A Institute of Medicine report describes a range of interventions for mental disorders that included treatment and maintenance, reserving the term "prevention" for efforts that occur before onset of...

Magnetoencephalography (MEG) records the magnetic field generated by electrical activity of cortical neurons. The signal is not distorted or attenuated, and it is contactless recording that can be performed comfortably even for longer than an hour. It has excellent and decent temporal resolution, especially when it is combined with the patient's own brain magnetic resonance imaging (magnetic source imaging). Data...

Exhaled nitric oxide (NO) has been extensively investigated as a noninvasive marker of airway inflammation in asthma. The increased NO expression induced by inflammatory mediators in airways can be monitored easily in exhaled air from asthmatic children. Based on the relationship between the increased NO expression and eosinophilic airway inflammation, fractional exhaled nitric oxide (FeNO) measurements become an important adjunct...

Vitamin D is an essential component of bone and mineral metabolism; its deficiency causes growth retardation and skeletal deformities in children and osteomalacia and osteoporosis in adults. Hypovitaminosis D (vitamin D insufficiency or deficiency) is observed not only in adults but also in infants, children, and adolescents. Previous studies suggest that sufficient serum vitamin D levels should be maintained in...

Kawasaki disease (KD) is an acute febrile illness that is the predominant cause of pediatric acquired heart disease in infants and young children. Because the diagnosis of KD depends on clinical manifestations, incomplete cases are difficult to diagnose, especially in infants younger than 1 year. Incomplete clinical manifestations in infants are related with the development of KD-associated coronary artery abnormalities....

A complex interplay between genetic and environmental factors partially contributes to the development of allergic diseases by affecting development during prenatal and early life. To explain the dramatic increase in the prevalence of allergic diseases, the hygiene hypothesis proposed that early exposure to infection prevented allergic diseases. The hygiene hypothesis has changed to the microbial hypothesis, in which exposure to...

The ketogenic diet (KD) is an established, effective, nonpharmacologic treatment for children with pharmacoresistant epilepsy. Although the KD is the most well-established dietary therapy for epilepsy, it is too restrictive and is associated with serious complications; therefore, alternative lower-fat diets, including a modified Atkins diet and low-glycemic index diet, have been developed. Recent ongoing clinical evidence suggests that other dietary...

Quality of life in addition to various medical problems in children with end-stage renal disease (ESRD) should be objectively assessed to accomplish normal growth and development during childhood. However, unfortunately, studies of quality of life (QoL) in children with ESRD have been not popular yet and there are only fewer suitable assessment tools compared with adults. Recently, disease-specific modules to...

Recent trends place an emphasis on school health care, the ultimate goal of which is to protect, maintain, and promote students' health. School health care is a program that integrates health care services, health education, health counseling, and local social health services. The student health examination (SHE) system is a part of school health care and schools and communities must...

Temporal lobe epilepsy (TLE) is the most common type of medically intractable epilepsy in adults and children, and mesial temporal sclerosis is the most common underlying cause of TLE. Unlike in the case of adults, TLE in infants and young children often has etiologies other than mesial temporal sclerosis, such as tumors, cortical dysplasia, trauma, and vascular malformations. Differences in...

Brain insults, including neurotrauma, infection, and perinatal injuries such as hypoxic ischemic encephalopathy, generate inflammation in the brain. These inflammatory cascades induce a wide spectrum of cytokines, which can cause neuron degeneration, have neurotoxic effects on brain tissue, and lead to the development of seizures, even if they are subclinical and occur at birth. Cytokines are secreted by the glial...

Repair of tetralogy of Fallot (TOF) has shown excellent outcomes. However it leaves varying degrees of residual hemodynamic impairment, with severe pulmonary stenosis (PS) and free pulmonary regurgitation (PR) at both ends of the spectrum. Since the 1980s, studies evaluating late outcomes after TOF repair revealed the adverse impacts of residual chronic PR on RV volume and function; thus, a...

This article contains the recommended immunization schedule by the Committee on Infectious Diseases of the Korean Pediatric Society, updated in March 2013, when Haemophilus influenzae type b vaccine is now included in the National Immunization Program in Korea. It also includes catch-up immunization schedule for children and adolescents who are behind the recommended schedule. These schedules are a minor revision...

Fluoroquinolones are an important class of antibiotics that are widely used in adult patients because of their broad spectrum of activity, good tissue penetration, and oral bioavailability. However, fluoroquinolone use in children is limited because juvenile animals developed arthropathy in previous experiments on fluoroquinolone use. Indications for fluoroquinolone use in patients younger than 18 years, as stated by the U.S....

Severe childhood asthma is a complicated and heterogeneous disorder with distinct phenotypes. Children with severe asthma have more persistent symptoms despite receiving treatment, more atopy, greater airway obstruction, and more air trapping than those with mild-to-moderate asthma. They also have higher morbidity and substantial airflow limitations that persist throughout adulthood. Identification of the phenotype clusters and endotypes of severe asthma...

Endoscopic treatment is a minimally invasive treatment for managing patients with vesicoureteral reflux (VUR). Although several bulking agents have been used for endoscopic treatment, dextranomer/hyaluronic acid is the only bulking agent currently approved by the U.S. Food and Drug Administration for treating VUR. Endoscopic treatment of VUR has gained great popularity owing to several obvious benefits, including short operative time,...