2015年 · 第53卷第03期

bronchiolitis, acute infectious bronchiolitis, is one of the most common infectious diseases of the lower respiratory tract in infants and young children. Data from different countries show that it is also the most common disease among children hospitalized during the epidemic season and a common cause of transfer to the pediatric intensive care unit due to respiratory failure^[1]。 For many years, pediatric clinicians and researchers in China have been paying attention to the study of the etiology, genetic background and pathogenesis of bronchiolitis. As early as 1950s, the Capital Institute of Pediatrics determined that respiratory syncial virus (RSV) is the first pathogen of infant bronchiolitis in China through virus isolation and culture technology. In recent years, clinicians from all over the world have also carried out beneficial attempts in the treatment of bronchiolitis^[2,3]。 In 2011, the editorial committee of Chinese Journal of Pediatrics organized the "Academic Symposium on Prevention and Treatment of Bronchiolitis in Children". Experts fully combed and analyzed the basic and clinical theory of bronchiolitis and the research results from all over the country, and thought that it was necessary to standardize the clinical diagnosis, treatment and prevention of bronchiolitis. Therefore, we refer to relevant foreign guidelines for diagnosis and prevention^[4,5,6]In particular, refer to the latest "Clinical Practice Guidelines for the Diagnosis, Treatment and Prevention of Bronchiolitis" issued by the American Academy of Pediatrics in 2014^[4]On the basis of China's actual situation and the consensus of experts in related fields^[7,8]After repeated discussion and review, the 2014 edition of the "Expert Consensus on Diagnosis, Treatment and Prevention of Bronchiolitis" (referred to as the "Expert Consensus") was formulated for pediatricians to apply in clinical practice. "Expert consensus" is mainly applicable to children with infectious bronchiolitis who are younger than 1 year old and have the first wheezing attack.

In addition to its effect on bone health, vitamin D is also related to chronic diseases such as cardiovascular and cerebrovascular diseases, diabetes, metabolic syndrome, malignant tumors, autoimmune diseases, multiple sclerosis, depression, tuberculosis, asthma, infant infection and even HIV infection^[1,2]。 There are 25 (OH) D-1 α-hydroxylase and vitamin D receptors in many organs and tissues of the body, which have the ability to convert 25 (OH) D into 1,25 (OH) in these tissues₂The ability of D to activate vitamin D receptors and alter target gene transcription by autocrine and/or paracrine means to exert corresponding biological effects (such as promoting cell differentiation, inhibiting tumor cell proliferation, anti-inflammatory, anti-angiogenic, immunomodulatory, and regulating other hormone systems, etc.). Both dietary intake of vitamin D and vitamin D (sunlight vitamin D) produced by ultraviolet irradiation are first hydroxylated in mitochondria of hepatocytes to generate 25 (OH) D; Second hydroxylation in the kidney, producing 1,25 (OH)₂D. 1,25 (OH)₂D is the active form, and when vitamin D deficiency is severe, 1,25 (OH)₂D is compensatingly elevated, thus 1,25 (OH)₂D level can not accurately evaluate the nutritional status of vitamin D in the body. As a metabolic intermediate product of vitamin D, 25 (OH) D has a half-life of several weeks, which is not affected by parathyroid hormone, blood calcium, blood phosphorus, etc. It reflects the total amount of dietary intake of vitamin D and sunlight vitamin D. Therefore, serum 25 (OH) D is used as a gold index to reflect the nutritional status of vitamin D^[3]。

Bronchiolitis, that is, acute infectious bronchiolitis, mainly occurs in infants and young children under 2 years old, and the peak onset age is 2~6 months old; The main clinical manifestations were runny nose, cough, paroxysmal wheezing, shortness of breath, inspiratory depression of chest wall (three concave signs), prolonged expiratory phase during auscultation, audible wheezing and fine damp rales; Infection involves bronchioles with a diameter of 75~300 m. Acute inflammation, mucosal edema, epithelial cell necrosis and increased mucus secretion, resulting in bronchiolar stenosis and obstruction are the pathological basis of this disease. The most common cause of bronchiolitis is viral infection, especially respiratory syncytial virus (RSV) infection. Infants<6 months of age and at high risk have a higher mortality rate^[1,2]。

The child was a male, Han nationality, 1 year and 9 months old. He was admitted to hospital because of "shortness of breath for more than 1 year, aggravated with low urine, edema, poor appetite and cough for 10 days". Children usually have shortness of breath, easy to catch colds, laborious feeding, easy to sweat, and normal growth and development. Since the age of 5 months, he has been admitted to our hospital four times due to edema, abdominal distension and cough (two of which were complicated with pneumonia). In the past, he has been diagnosed with "endocardial fibroelastosis (EFT)", and has been given digoxin, spironolactone, captopril, low-dose prednisone and nutritional myocardial drugs for a long time, but the symptoms are not relieved. Children in 39^＋5Delivered by caesarean section, birth weight 3.2 kg. There was no history of special discomfort or exposure to special substances during pregnancy, and no abnormalities were found in routine prenatal examination. The child had an elder sister, 11 years old, in good health, and an older brother, who died of "EFT" at the age of 8 months.

A 2-month-old male was admitted to the Provincial Hospital affiliated to Shandong University for the first time on August 8, 2013 due to "fever for 10 days and cough for 5 days". Three months later, the child was admitted to hospital for the second time on November 26, 2013 because of "fever for more than 10 days and cough for 5 days after finding a perianal abscess for 1 month". The child was the first birth, the first birth, a full-term natural birth, and was healthy after birth. He had been vaccinated with BCG and hepatitis B vaccine on time. There was no obvious abnormality in his personal and family history. His father complained that the living environment was slightly humid.

Recent studies have found that almost all tissues and organs of the human body express vitamin D receptor, and the pleiotropy of vitamin D also makes it a hormone that attracts much attention. Many of the effects of vitamin D have also been found to exist outside the feedback loop that is independent of serum calcium, phosphorus, and parathyroid hormone levels. The relationship between vitamin D deficiency and rickets has been the main research content of researchers, but recent studies have pointed out that vitamin D is related to many non-skeletal diseases such as cancer, autoimmune diseases, metabolic diseases, cardiovascular diseases and respiratory diseases^[1]。 Bronchial asthma, allergic rhinitis, food allergy and eczema are the most common chronic allergic diseases, and their incidence is increasing year by year. There are inconsistent reports on the relationship between vitamin D deficiency and incidence and severity of allergic diseases. The immunomodulatory role of vitamin D in allergic diseases has attracted more and more attention from domestic and foreign scholars. The immune mechanism of allergic occurrence is affected by many factors, among which the disorder of Th1/Th2 balance and the abnormal high expression of Th2 cytokines play an important role in its pathogenesis. The following is a review of the relationship between vitamin D and allergic diseases and its immunomodulatory mechanism.

The role of vitamin D in promoting calcium and phosphorus metabolism and maintaining bone health has been widely recognized. With the deepening of research, the role of vitamin D in human cognitive function, respiratory system, circulatory system, autoimmune system and cancer occurrence has gradually been recognized^[1,2]。 At the same time, due to the change of modern living habits, the time people are exposed to sunlight has been significantly reduced, and the increase in the occurrence of vitamin D deficiency and deficiency has also been valued. The need for infants, pregnant women and the elderly to supplement an appropriate amount of vitamin D has been affirmed again, and the number of people who supplement vitamin D has a trend of expanding, and the dose of supplement has also increased. However, vitamin D is a fat-soluble steroid derivative, and excess vitamin D can accumulate in the human body, leading to hypercalcemia and a series of clinical symptoms, namely, vitamin D overdose or poisoning. Although vitamin D overdose or poisoning is quite rare, it is necessary to pay attention to vitamin D overdose and poisoning with the formation of recent research hotspots on vitamin D and health and the increase in the use of vitamin D supplements in the population. Recent studies on the mechanism of vitamin D overdose and poisoning and related case reports as well as the diagnosis and intervention of vitamin D poisoning are reviewed in order to increase the attention of clinical workers.

The 10th National Academic Conference on Children's Digestive System Diseases, sponsored by the Gastroenterology Group of Pediatrics Branch of Chinese Medical Association and the Editorial Committee of Chinese Journal of Pediatrics, and co-organized by Quanzhou Children's Hospital of Fujian Province, was held in Quanzhou, Fujian Province from April 16 to 18, 2014. A total of 214 manuscripts and 705 registered delegates were received at this conference. The conference was rich in content and covered a wide range of topics, covering many fields such as children's gastrointestinal, liver disease and nutrition. It not only aims at the needs of grass-roots clinicians in clinical practice, but also involves the latest progress in basic research and various fields. There were 18 special lectures, 20 conference speeches and 2 difficult case discussions. Experts and representatives participating in the conference had full exchanges and discussions, and commended outstanding conference speeches and outstanding difficult case discussions. At the opening ceremony, Professor Dong Yongsui of Tongji Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology deeply remembered the outstanding contribution made by Professor Song Mingtong, a famous medical educator in China, to the development of pediatrics in China, and deeply reviewed the establishment and growth process of pediatric gastroenterology group in China, and put forward hope for the development of pediatric gastroenterology in China. The main contents of the meeting are now summarized.