Posterior fossa malformations are rare cyst-like pathologies of the central nervous system. Outcomes of patients with these conditions are largely documented in fetal or early childhood studies as most cases are non-compatible with life. Also, different schemes to categorize these occurrences have been proposed. One classification puts forth that the entities are a continuum of pathologies, called the Dandy Walker Complex, wherein Mega Cisterna Magna is the most benign to Dandy Walker Malformation as the most severe form. We report the first case of a patient with a mixed presentation of Mega Cisterna Magna having extracranial manifestations of Dandy Walker Malformation reaching her adult years. The patient is a 26-year-old female who was apparently well until she presented with recurrent headache and seizure episodes of 2-year duration. She had an unremarkable birth and childhood history, apart from learning difficulties in school. In her adult years, she gave birth to an infant with multiple physical anomalies. She has a maternal uncle with abnormal facie and intellectual disability. Physical examination of the patient exhibited a bulging occiput, hypertelorism, down-slanting palpebral fissures, large globular nose, large ear lobules, high arched palate, and clinodactyly. Neurologic examination was unremarkable. Magnetic resonance imaging confirmed Mega Cisterna Magna and was deemed non-surgical. She remained seizure-free during admission as well as on followup, maintained on Phenytoin. The existence of a Dandy-Walker continuum is still debated, as the link among the disease entities are yet to be established using developmental or genetic studies. This case, however, supports the Dandy-Walker Complex classification by demonstrating a rare combination of Mega Cisterna Magna with features of Dandy-Walker Malformation in an adult. This can contribute to disease definition and eventually to the discovery of the pathobiological mechanisms of posterior fossa cysts, and to appropriate diagnosis and management.

A boy, aged 16 months, attended the hospital due to head and facial erythema for 15 months and vulva erythema for 10 months with aggravation for 5 days. The boy developed perioral and periocular erythema in the neonatal period and had erythema and papules with desquamation and erosion in the neck, armpit, and trigone of vulva in infancy. Blood gas analysis showed metabolic acidosis; the analysis of amino acid and acylcarnitine profiles for inherited metabolic diseases and the analysis of organic acid in urine suggested multiple carboxylase deficiency; genetic testing showed a homozygous mutation of c.1522C>T(p.R508W) in the HLCS gene. Finally the boy was diagnosed with holocarboxylase synthetase deficiency and achieved a good clinical outcome after oral biotin treatment. This article analyzes the clinical data of a child with holocarboxylase synthetase deficiency and summarizes the etiology, diagnosis, and treatment of this child, so as to provide ideas for clinicians to diagnose this rare disease.
Humans ; Male ; Biotin/therapeutic use* ; Holocarboxylase Synthetase Deficiency/drug therapy* ; Homozygote ; Mutation ; Rare Diseases/drug therapy* ; Infant

Rare diseases in children are characterized by low prevalence, complex pathogenesis, variety, and difficulty in the diagnosis and treatment. With the development of medical services, progress has been made in the diagnosis and treatment of rare diseases. However, due to asymmetric allocation of medical resources at different levels, there are still many shortcomings in the establishment and promotion of the homogenized management system of rare disease diagnosis and treatment. In order to further standardize the homogenized management of rare diseases in children, achieve early and accurate diagnosis and treatment, and improve the quality of life of the children, the Rare Disease Diagnosis and Treatment Center of Tianjin Children's Hospital (Tianjin University Children's Hospital) invited relevant experts in the field to develop recommendations for the management model of homogenized diagnosis and treatment of rare diseases in children from the aspects of information construction, hierarchical diagnosis and treatment, personnel training, scientific popularization, and multi-participation. The recommendations provide reference for the regional homogenization of clinical diagnosis and treatment management system for children with rare diseases.
Humans ; Child ; Rare Diseases/therapy* ; Quality of Life

There are more than 7 000 rare diseases and approximately 475 million individuals with rare diseases globally, with children accounting for two-thirds of this population. Due to a relatively small patient population and limited financial resources allocated for drug research and development in pharmaceutical enterprises, there are still no drugs approved for the treatment of several thousands of these rare diseases. At present, there are no drugs for 95% of the patients with rare diseases, and consequently, the therapeutic drugs for rare diseases have been designated as orphan drugs. In order to guide pharmaceutical enterprises to strengthen the research and development of orphan drugs, various nations have enacted the acts for rare disease drugs, promoted and simplified the patent application process for orphan drugs, and provided scientific recommendations and guidance for the research and development of orphan drugs. Since there is a relatively high incidence rate of rare diseases in children, this article reviews the latest research on pharmacotherapy for children with rare diseases.
Humans ; Child ; Rare Diseases/drug therapy* ; Orphan Drug Production ; Pharmaceutical Preparations

Humans ; Decision Support Systems, Clinical ; Rare Diseases/therapy*

Rare diseases refer to a group of single diseases with low incidence rates, complex pathogeneses, severe disease conditions, and rapid progression. Most rare diseases have a genetic background and may occur in childhood. Paying attention to the rare genetic diseases in children and performing early diagnosis and treatment can effectively delay the course of disease and improve the quality of life of children. Many rare diseases can be diagnosed with the help of various experimental techniques, but the diagnosis of rare diseases is still not widely understood. This article summarizes the laboratory diagnostic techniques currently used for rare genetic diseases in children, so as to provide clues for the diagnosis and treatment of such diseases and help to enhance the theoretical understanding and precise medical treatment of rare genetic diseases in children.
Child ; Humans ; Rare Diseases/therapy* ; Quality of Life

ACGS Best Practice Guidelines for Variant Classification in Rare Disease 2020, a supplementary practical guidelines, is based on the Standards and Guidelines for the Interpretation of Sequence Variations issued by the American Society for Medical Genetics and Genomics (ACMG) and the Association of Molecular Pathology (AMP) in 2015 by the British Medical Genetics Society under the Clinical Genomics Society (ACGS), and has integrated the detailed rules of standards developed by the ClinGen Sequence Variant Interpretation (SVI) Working Group by 2020. The further development of the ACMG/AMP guidelines is currently undertaken by the ClinGen SVI working group in the United States, which focuses on the classification of high penetrance and protein coding variants. ClinGen has established many expert panels on variants for specific diseases which required various evidence thresholds and is currently developing disease/gene specific guidelines. The British Medical Genetics Society has collected and integrated information on the guidelines for sequence variation classification and their extended rules, forming its own "2020 ACGS Best Practice Guidelines for Rare Disease Variation Classification" and is regularly updating it. The author has translated and summarized it for the reference of Chinese Medical Genetics Practitioners.
Humans ; Genetic Testing ; Genetic Variation ; Genome, Human ; Rare Diseases/genetics* ; China

OBJECTIVE: To summarize the clinical features and biological characteristics of Helsmoortel Van der Aa syndrome (HVDAS) due to hotspot mutations of the ADNP gene in order to facilitate early diagnosis. METHODS: Clinical data and result of genetic testing for a girl with HVDAS due to hotspot mutation of the ADNP gene was summarized. Related literature was also reviewed. RESULTS: The patient, a 2-year-old girl, had presented with growth retardation, facial dysmorphism, psychomotor and language delay and recurrent respiratory infections. Whole exome sequencing revealed that she has harbored a heterozygous c.2496_2499delTAAA (p.Asn832Lysfs*81) variant of the ADNP gene, which was not found in either of her parents. CONCLUSION Although the typical features of the HVDAS have included intellectual disability and autism spectrum disorders, growth retardation and premature primary tooth eruption may also be present. In addition, the phenotypic difference among individuals carrying hot spot variants of the ADNP gene was not prominent.
Humans ; Female ; Child, Preschool ; Intellectual Disability/genetics* ; Homeodomain Proteins/genetics* ; Nerve Tissue Proteins/genetics* ; Abnormalities, Multiple/genetics* ; Mutation ; Rare Diseases ; Growth Disorders/genetics*

A boy, aged 6 years, attended the hospital due to global developmental delay for 6 years and recurrent fever and convulsions for 5 years. The boy was found to have delayed mental and motor development at the age of 3 months and experienced recurrent fever and convulsions since the age of 1 year, with intermittent canker sores and purulent tonsillitis. During the fever period, blood tests showed elevated white blood cell count, C-reactive protein, and erythrocyte sedimentation rate, which returned to normal after the fever subsides. Electroencephalography showed epilepsy, and genetic testing showed compound heterozygous mutations in the GPAA1 gene. The boy was finally diagnosed with glycosylphosphatidylinositol biosynthesis deficiency 15 (GPIBD15) and periodic fever. The patient did not respond well to antiepileptic treatment, but showed successful fever control with glucocorticoid therapy. This article reports the first case of GPIBD15 caused by GPAA1 gene mutation in China and summarizes the genetic features, clinical features, diagnosis, and treatment of this disease, which provides a reference for the early diagnosis and treatment of GPIBD15.
Humans ; Male ; Fever ; Glycosylphosphatidylinositols/genetics* ; Membrane Glycoproteins/genetics* ; Mutation ; Rare Diseases ; Seizures ; Child

In recent years, China's anti-tumor drugs has shown a continuous growth trend, and the activity of anti-tumor research and development in China accounts for a higher proportion in the world. However, further analysis of research and development hotspots show that the research and development of anti-tumor drugs is uneven among different tumor types. Due to the small number of the patients, it is difficult to conduct clinical trials, resulting in less drug development in the field of rare tumors. However, patients' treatment needs will also bring potential opportunities for pharmaceutical companies. The development of basic research and the discovery of new molecular tumor typing make "rare tumors" a dynamic concept. The scope of "rare tumors" may gradually expand with the precise development of treatment; or as the knowledge of tumors gradually develops from histocytology to the molecular level, It is possible that certain tumors with specific mutations can be combined into a group of non-rare "pan-tumors". Rare tumors are characterized by both rare diseases and tumors. Its drug research and development should not only meet the requirements of tumor drug research and development, but also adapt to the characteristics of rare diseases. Therefore, in the drug research and development, we can refer to the research and development principle of rare disease drugs, combine with the characteristics of tumor diseases, make full use of non-rare tumor clinical trials, make full use of scientific tools and exquisite trial design, and realize the promotion of the research and development of rare tumor drugs. This paper will summarize the thoughts in the review of new drugs in the field of rare tumors, in order to provide guidance for the industry.
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Antineoplastic Agents/therapeutic use* ; China ; Humans ; Lung Neoplasms/drug therapy* ; Rare Diseases/drug therapy* ; Research