Respiratory complications and sleep disorders in children with chronic kidney disease: A correlation often underestimated.

Chronic Kidney Disease (CKD) is characterized by a progressive and irreversible loss of kidney function which gradually leads to end-stage kidney disease (ESKD). Virtually all the organs are damaged by the toxicity of uremic compounds. The lungs may be affected and the impaired pulmonary function may be the direct result of fluid retention and metabolic, endocrine and cardiovascular alterations, as well as systemic activation of the inflammation. An increased prevalence in sleep disorders (SD) is also reported in patients with CKD, leading to a further negative impact on overall health and quality of life. While these complex relationships are well documented in the adult population, these aspects remain relatively little investigated in children. The aim of this review is to provide a brief overview of the pathophysiology between lung and kidney and to summarize how CKD may affect respiratory function and sleep in children.

Pediatric norovirus infection.

Noroviruses (NoVs) are among the most frequent causes of acute pediatric gastroenteritis. Although the disease is often self-limiting and recovery is the rule, it constitutes an important health problem because of its highly contagious nature and the high rate of morbidity. NoVs are responsible for 47-96 % of outbreaks of acute pediatric gastroenteritis, and 5-36 % of sporadic cases. NoV-induced gastroenteritis is a frequent cause of hospitalization, and severe and sometimes fatal cases have been reported in immunocompromised children. The increasing recognition of NoVs as the cause of pediatric disease and the limited success in preventing outbreaks have led to consideration of vaccines. However, while awaiting the development of a vaccine, there is an urgent need for more epidemiological data concerning childhood NoV infection, including the impact of NoVs on different age groups, the possible etiological role of NoVs in infections other than gastroenteritis, and the socioeconomic impact of NoVs on households.

Current advances in the understanding and treatment of mevalonate kinase deficiency.

Mevalonate kinase deficiency (MKD) is a rare autosomal recessive autoinflammatory metabolic disease that is caused by mutations in the MVK gene. Patients with MKD typically have an early onset in infancy. MKD is characterized by recurrent episodes of high fever, abdominal distress, diffuse joint pain, and skin rashes. In a subset of patients, MKD is also associated with elevated serum immunoglobulin D (IgD) levels (hyperimmunoglobulinemia D syndrome, HIDS). The clinical phenotype of MKD varies widely and depends on the severity of the impaired mevalonate kinase activity. Complete impairment results in the severe metabolic disease, mevalonic aciduria, while a partial deficiency results in a broad spectrum of clinical presentation, including HIDS. The precise molecular mechanisms behind the elevated serum IgD levels and inflammation that occurs in MKD remain unknown. Children who exhibit symptoms of MKD should be tested for mutations in the MKD gene. However, the complexity of MKD often results in delays in its definitive diagnosis and the outcome in adult age is not completely known. Therapeutic options for MKD are based on limited data and include non-steroidal anti-inflammatory drugs, corticosteroids, and biological agents that target specific cytokine pathways. In recent years, some studies have reported promising results for new biological drugs; however, these cases have failed to achieve satisfactory remission. Therefore, further studies are needed to understand the pathogenesis of MKD and identify innovative therapeutic tools for its management.

Clinical presentation of meningococcal disease in childhood.

Although relatively rare, meningococcal disease represents a global health problem being still the leading infectious cause of death in childhood with an overall mortality around 8%. Meningococcal meningitis is the most commonly recognized presentation, accounting for 80% to 85% of all reported cases of meningococcal disease (in half of these cases sepsis is also present concomitantly). The remaining 15-20% of cases are most commonly bloodstream infections only. Meningococcal serogroups A, B, and C account for most cases of meningococcal disease throughout the world. Recently, serogroups W-135 and X (predominantly in Africa) and group Y (in the United States and European countries) have emerged as important disease-causing isolates. Despite recent advances in medical management, the mortality rate of fulminant meningococcemia ranges from 15% to 30%. However, among survivors, 10-30% could have long term sequelae (i.e. sensoneural hearing loss, seizure, motor problems, hydrocephalus, mental retardation, and cognitive and behavioral problems). Considering the clinical severity of meningococcal disease, prevention represents the first approach for avoiding serious complications and possible deaths. The availability of new vaccines able to cover the emerging serotypes including A and Y as well as the availability on the market of new products that could prevent meningococcal B infection represent a great opportunity for the decrease of the burden of this complicated disease.