Autism spectrum disorder（ASD）is a serious neurodevelopmental disorder，with deficits in social and language communication，rigid behaviors，limited interests and activities. At present，research on the pathogenesis of ASD involving immunity has been making progress worldwide. In terms of cytokines（such as IL-1β，IL-8，IL-17，etc.）and ASD animal models，it has been found that the onset of ASD is associated with nervous system immune dysfunction，which may lead to synaptic function impairment. The purpose of this review is to describe the recent research on ASD and immune dysfunction to provide ideas for exploring the etiology，pathogenesis and potential therapeutic measures of ASD.

Acute leukemia（AL）is a common hematological malignancy in children and adolescents. Chemotherapy is currently the primary treatment for AL.Alternative therapies，such as hematopoietic stem cell transplantation（HSCT），targeted therapy，and immunotherapy also offer greater hope for the survival of refractory/relapsed patients. Chemotherapeutic drugs，radiotherapy，targeted drugs and immunotherapeutic drugs are well-applied clinically，meanwhile posing threats to non-target systems. The adverse effects on the reproductive system may lead to the dilemma of infertility，thus reducing the long-term quality of life. As the survival rate of AL patients keeps increasing continuously，the influence of different treatments on the gonad function needs to be clarified. With the help of targeted fertility prevention，the patient′s quality of life can be enhanced in parallel with life span. This article aims to review the impact of AL treatment on ovarian function in female children and adolescents and provide ideas for the long-term fertility protection of leukemia patients.

Eosinophils are generally considered to play an important role in parasitic infections and allergic diseases. In recent years，eosinophils have also been found to be involved in the host's immune response to infections caused by bacteria，viruses and fungi. Eosinophils recognize these pathogens through pattern recognition receptors，during this process multiple mechanisms are implicated in host's immune defense against infections. Much progress on the role of eosinophils in respiratory tract infections has been reported in recent years. This review summarizes the regulatory role of eosinophils in respiratory infectious diseases，and the activation process of eosinophils and their direct and indirect interaction with respiratory pathogens，hoping to improve the recognition of the role of eosinophils in the pathogenesis of respiratory infectious diseases，and provide new ideas for clinical diagnosis and treatment.

In recent years，the prevalence of childhood obesity has increased rapidly，and obesity can seriously affect physical and mental health of children and adolescents，and is likely to extend into adulthood. The onset and development of childhood obesity is related to multiple factors such as genetic predisposition and environment. So far，more and more studies have found that the gut microbiota，as an important part of the internal environment，is closely related to childhood obesity. Perturbed gut microbiota and its derived metabolites such as short-chain fatty acids，bile acids，indole and their derivatives are widely involved in the onset and development of childhood obesity. At present，regulating the compositions and function of gut microbiota through probiotics and prebiotics，fecal microbiota transplantation，dietary intervention，and bariatric surgery is a new direction for the prevention and treatment of obesity. This paper reviews the research progress on the association between gut microbiota and childhood obesity，in order to provide novel insights for prevention and intervention of childhood obesity based on gut microbiota.

Neurofibromatosis type 1（NF1）is one of the most common autosomal dominant disorders. The disease is caused by mutations in the NF1 gene，which can involve multiple systems and have a variety of clinical manifestations，including café au lait macules，lisch nodules，neuroglioma，autism spectrum disorder，learning difficulties，neurofibromas，and skeletal dysplasia，et al.In previous studies on the pathogenesis of NF1，most of them have focused on the regulation of the RAS signaling pathway by neurofibromin. In recent years，researchers start exploring pathways other than RAS signaling to explore the potential functions of neurofibromin. This article reviews the research progress on the pathogenesis of NF1 in recent years，aiming to provide new ideas for treatment.

Acute lymphoblastic leukemia（ALL）is the most common pediatric cancer and has good outcome.However，the prognosis of relapsed/refractory ALL in children is poor.Intensive reinduction chemotherapy and hematopoietic stem cell transplantation have become alternative treatments. Bortezomib，as the primary generation proteasome inhibitor，has been approved for the treatment of multiple myeloma and mantle cell lymphoma. In recent years，several clinical studies have confirmed promising responses and well tolerated of bortezomib combined with various chemotherapeutic drugs in treating children with relapsed/refractory ALL，to improve the complete remission rate and survival rate. This article reviews the mechanisms of bortezomib in ALL and the clinical study progress and safety of bortezomib combined with chemotherapy in children with relapsed/refractory ALL.

Congenital anomalies of the kidneys and urinary tracts（CAKUT）include a wide range of structural malformations resulting from defects in the morphogenesis of the kidney and the urinary tract. Congenital renal anomaly is common in CAKUT. The pathogenesis of congenital renal anomaly is considered to be multi-factor，involving maternal or external environment，and heredity. With the continuous progress of molecular diagnosis technology，genetic factors have attracted more and more attention. The PBX1 gene was initially discovered by the formation of an E2A-PBX1 fusion gene from a t（1；19）（q23；p13.3）chromosome translocation，which results in pre-B-cell lymphoblastic leukemia.PBX1 gene mutation can cause congenital renal and urogenital malformation syndromes with or without hearing loss，ear abnormalities，and developmental delay. This review deepens the understanding of the role of genes in regulating kidney development by describing the embryonic basis of kidney development，the structure and function of the PBX1 gene，and the pathogenesis of renal anomalies caused by mutations. Further，it summarizes the phenotype and genotype of the PBX1 gene，in order to promote the diagnosis，treatment，and determination progression of congenital renal anomaly.

Airway mucus hypersecretion is one of the pathological changes in children with community acquired pneumonia（CAP），and affects the severity，progression and prognosis of CAP.Diagnosis of airway mucus hypersecretion currently relies on fiberoptic bronchoscopy. To predict the risk of airway mucus hypersecretion and to take early action to avoid serious consequences such as plastic bronchitis and hypoxia and respiratory failure，the article summarizes the relationship between age，clinical characteristics and laboratory indices and the formation of airway mucus hypersecretion in children with CAP. Among them，age，pathogenic species，fever peak and fever range，neutrophil ratio，C-reactive protein，lactate dehydrogenase，D-dimer，serum 25（OH）D，and some interleukins，interferons，and acquired immune indicators have an early warning effect on the development of airway mucus hypersecretion in children with CAP.

Community acquired pneumonia（CAP）is the leading cause of death in children，and as molecular diagnostic techniques continue to improve，more CAP is found to be caused by viral infections. At present，many factors are known to affect the severity of viral pneumonia，including viral subtypes，viral virulence，host factors，environmental factors，etc. Some studies have found that viral load is related to the severity of viral pneumonia，and different viral load levels have different effects on the severity of viral pneumonia. The correlation with virus type，subtype，site of virus specimen collection，age，sex and co-infection may be also different. This article will review the relationship between viral load and disease severity in pneumonia caused by common respiratory viral infections.

Streptococcus pneumoniae infection is a common respiratory disease in children. Globally，invasive pneumococcal disease（IPD），which is caused by Streptococcus pneumoniae infection，is one of the leading causes of death in children. The use of Streptococcus pneumoniae vaccine has provided protection for children to some extent，but the prevalence of pathogenic and drug-resistant non-vaccine type（NVT）Streptococcus pneumoniae poses a grave threat to children's health. Due to the different use of vaccines and antibiotics in different regions，there are regional variations in the NVT distribution. This paper reviews the pathogenic process of Streptococcus pneumoniae，the mechanism of NVT production，the geographical distribution and the pathogenic condition of NVT，in order to fully understand the pathogenicity and harm of NVT，to provide data support for the adjustment of health strategy，and to provide reference for clinical diagnosis and treatment and future vaccine development and use.