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...

Cystic fibrosis (CF) is a genetic disease with autosomal recessive inheritance and is common in Caucasian people. The prevalence of this disease is between 1/2,000 and 1/3,500 live births, and the incidence varies between populations. Although the CF transmembrane conductance regulator gene is expressed in the kidneys, renal involvement is rare. With advances in the treatment of CF, life expectancy...

Kabuki syndrome (KS) is a rare genetic disease with a distinctive dysmorphic face, intellectual disability, and multiple congenital abnormalities. KS is inherited in an autosomal dominant manner. As the primary cause of KS, MLL2 mutations have been identified in 56-76% of affected individuals who have been tested, suggesting that there may be additional genes associated with KS. Recently, a few...

Wiskott-Aldrich syndrome (WAS) is an inherited X-linked disorder. The WAS gene is located on the X chromosome and undergoes mutations, which affect various domains of the WAS protein, resulting in recurrent infection, eczema, and thrombocytopenia. However, the clinical features and severity of the disease vary according to the type of mutations in the WAS gene. Here, we describe the case...

Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is characterized by a severe idiosyncratic reaction including rash and fever, often with associated hepatitis, arthralgias, lymph node enlargement, or hematologic abnormalities. The mortality rate is approximately 10%, primarily owing to liver failure with massive or multiple disseminated focal necrosis. Here, we report a case of a 14-year-old girl treated with...

Prader-Willi syndrome (PWS) is a complex multisystem genetic disorder characterized by hypothalamic-pituitary dysfunction. The main clinical features include neonatal hypotonia, distinctive facial features, overall developmental delay, and poor growth in infancy, followed by overeating with severe obesity, short stature, and hypogonadism later in development. This paper reviews recent updates regarding the genetic aspects of this disorder. Three mechanisms (paternal deletion,...

Rubinstein-Taybi syndrome (RTS) is characterized by peculiar facies, mental retardation, broad thumbs, and great toes. Approximately one-third of the affected individuals have a variety of congenital heart diseases. They can also have upper airway obstruction during sleep, due to hypotonia and the anatomy of the oropharynx and airway, which make these patients susceptible to obstructive sleep apnea (OSA). In our...

Several authors suggested that the clinical characteristics of incomplete presentation of Kawasaki disease are similar to those of complete presentation and that the 2 forms of presentation are not separate entities. Based on this suggestion, a diagnosis of incomplete Kawasaki disease in analogy to the findings of complete presentation is reasonable. Currently, the diagnosis of incomplete Kawasaki disease might be...

Nephrotic syndrome (NS) is one of the most common glomerular diseases that affect children. Renal histology reveals the presence of minimal change nephrotic syndrome (MCNS) in more than 80% of these patients. Most patients with MCNS have favorable outcomes without complications. However, a few of these children have lesions of focal segmental glomerulosclerosis, suffer from severe and prolonged proteinuria, and...

Children who suffer from steroid-resistant nephrotic syndrome (SRNS) require aggressive treatment to achieve remission. When intravenous high-dose methylprednisolone fails, calcineurin inhibitors, such as cyclosporine and tacrolimus, are used as the first line of treatment. A significant number of patients with SRNS progress to end-stage renal disease if remission is not achieved. For these children, renal replacement therapy can also be...

McKusick-Kaufman syndrome (MKS) is an autosomal recessive multiple malformation syndrome characterized by hydrometrocolpos (HMC) and postaxial polydactyly (PAP). We report a case of a female child with MKS who was transferred to the neonatal intensive care unit of Seoul National University Children's Hospital on her 15th day of life for further evaluation and management of an abdominal cystic mass. She...

Hemolytic-uremic syndrome (HUS) is the most common cause of acute renal failure in young children. It is classically characterized by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and uremia. Further, not only is intussusception one of the differential diagnoses of HUS but it may also become a complication during disease progression. We report a case of HUS preceded by intussusception...

Prader-Willi syndrome (PWS) is a complex multisystem genetic disorder that is caused by the lack of expression of paternally inherited imprinted genes on chromosome 15q11-q13. This syndrome has a characteristic phenotype including severe neonatal hypotonia, early-onset hyperphagia, development of morbid obesity, short stature, hypogonadism, learning disabilities, behavioral problems, and psychiatric problems. PWS is an example of a genetic condition caused...

Bartter syndrome (BS) is a clinically and genetically heterogeneous inherited renal tube disorder characterized by renal salt wasting, hypokalemic metabolic alkalosis and normotensive hyperreninemic hyperaldosteronism. There have been several case reports of BS complicated by focal segmental glomerulosclerosis (FSGS). Here, we have reported the case of a BS patient who developed FSGS and subsequent end-stage renal disease (ESRD) and provided...

Townes-Brocks syndrome (TBS) is a rare autosomal dominant congenital disorder caused by mutations in the SALL1 gene. Its signs and symptoms overlap with other genetic syndromes, including VACTERL association, Pendred syndrome, Baller-Gerold syndrome, and cat eye syndrome. Structural vertebral abnormalities, hypoplasia of the thumb, and radial bone abnormalities, which are not usually associated with TBS, help in the differential diagnosis...

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...