Juvenile idiopathic arthritis (JIA) is comprised of a heterogeneous group of several disease subtypes that are characterized by the onset of arthritis before the age of 16 years and has symptoms lasting at least 6 weeks. The previous classification of JIA included seven different categories, whereas its current classification was compiled by the International League of the Association for Rheumatology,...

Juvenile rheumatoid arthritis (JRA) is the most common rheumatic childhood disease; its onset is before 16 years of age and it persists for at least 6 weeks. JRA encompasses a heterogeneous group of diseases that is classified according to 3 major presentations: oligoarthritis, polyarthritis, and systemic onset diseases. These presentations may originate from the same or different causes that involve...

Obstructive sleep apnea (OSA) in children is a frequent disease for which optimal diagnostic methods are still being defined. Treatment of OSA in children should include providing space, improving craniofacial growth, resolving all symptoms, and preventing the development of the disease in the adult years. Adenotonsillectomy (T&A) has been the treatment of choice and thought to solve young patient's OSA...

The prevalence of pediatric obstructive sleep apnea syndrome (OSAS) is approximately 3% in children. Adenotonsillar hypertrophy is the most common cause of OSAS in children, and obesity, hypotonic neuromuscular diseases, and craniofacial anomalies are other major risk factors. Snoring is the most common presenting complaint in children with OSAS, but the clinical presentation varies according to age. Agitated sleep with...

Crohn's disease is characterized by chronic inflammation involving any portion of the gastrointestinal tract. Treating Crohn's disease is a major challenge for clinicians, as no curative therapy currently exists. Pediatric Crohn's disease is characterized by frequent relapses, a wide extent of disease, a high prevalence of extraintestinal manifestations, and a severe clinical course. The classic therapeutic approach is known as...

The safety and effectiveness of colonoscopy in the investigation of lower gastrointestinal tract pathology in children has been established for more than 2 decades in Korea. Skill and experience have since advanced to the point that both diagnostic and therapeutic colonoscopy are now routinely performed by most pediatric gastroenterologists. Pediatric colonoscopy differs significantly from its adult parallels in nearly every...

Gastrointestinal and colonic endoscopic examinations have been performed in pediatric patients in Korea for 3 decades. Endoscopic procedures are complex and may be unsafe if special concerns are not considered. Many things have to be kept in mind before, during, and after the procedure. Gastrointestinal endoscopy is one of the most frequently performed procedure in children nowadays, Since the dimension...

Induced pluripotent stem (iPS) cells are generated by epigenetic reprogramming of somatic cells through the exogenous expression of transcription factors. Recently, the generation of iPS cells from patients with a variety of genetic diseases was found to likely have a major impact on regenerative medicine, because these cells self-renew indefinitely in culture while retaining the capacity to differentiate into any...

In pre-surgical evaluation of pediatric epilepsy, the combined use of multiple imaging modalities for precise localization of the epileptogenic focus is a worthwhile endeavor. Advanced neuroimaging by high field Magnetic resonance imaging (MRI), diffusion tensor images, and MR spectroscopy have the potential to identify subtle lesions. ¹⁸F-FDG positron emission tomography and single photon emission tomography provide visualization of metabolic alterations...

Renal fibrosis, characterized by tubulointerstitial fibrosis and glomerulosclerosis, is the final manifestation of chronic kidney disease. Renal fibrosis is characterized by an excessive accumulation and deposition of extracellular matrix components. This pathologic result usually originates from both underlying complicated cellular activities such as epithelial-to-mesenchymal transition, fibroblast activation, monocyte/macrophage infiltration, and cellular apoptosis and the activation of signaling molecules such as...

Congenital anomalies of the kidney and urinary tract (CAKUT) account for more than 50% of abdominal masses found in neonates and involve about 0.5% of all pregnancies. CAKUT has a major role in renal failure, and increasing evidence suggests that certain abnormalities predispose to the development of hypertension and cardiovascular disease in adulthood. To understand the pathogenesis of human renal...

An increase in the number of preterm infants and a decrease in the gestational age at birth have resulted in an increase in the number of patients with significant bronchopulmonary dysplasia (BPD) and secondary pulmonary hypertension (PH). PH contributes significantly to the high morbidity and mortality in the BPD patients. Therefore, regular monitoring for PH by using echocardiography and B-type...

Patients with congenital heart diseases (CHD) are confronted with early- and late-onset complications, such as conduction disorders, arrhythmias, myocardial dysfunction, altered coronary flow, and ischemia, throughout their lifetime despite successful hemodynamic and/or anatomical correction. Rhythm disturbance is a well-known and increasingly frequent cause of morbidity and mortality in patients with CHD. Predisposing factors to rhythm disturbances include underlying cardiac defects,...

The risk of mortality and morbidity of patients with congenital heart defects (CHDs) is highest during neonatal period and increases when diagnosis and proper management are delayed. Neonates with critical CHDs may present with severe cyanosis, respiratory distress, shock, or collapse, all of which are also frequent clinical presentations of various respiratory problems or sepsis in the newborn. Early diagnosis...

Pertussis is a highly contagious respiratory tract disease caused by Bordetella pertussis infection. The clinical manifestation of this infection can be severe enough to cause death. Although pertussis has been supposed to be a vaccine-preventable disease ever since the widespread vaccination of children against pertussis was started, since the 1990s, cases of pertussis and related fatalities are on the rise,...

The mumps virus is a single-stranded, non-segmented, negative-sense RNA virus belonging to the Paramyxoviridae family. Mumps is characterized by bilateral or unilateral swelling of the parotid gland. Aseptic meningitis is a common complication, and orchitis is also common in adolescents and adult men. Diagnosis is based on clinical findings, but because of high vaccination coverage, clinical findings alone are not...

Enterovirus 71 (EV71) has been recognized as a frequent cause of epidemics of hand-foot-and-mouth disease (HFMD) associated with severe neurological symptoms. In the spring of 2009, HFMD was epidemic in Korea. Severe cases with complication, including death, have been reported and it has become a public health issue. Most symptomatic EV71 infections commonly result in HFMD or herpangina. These clinical...