Japan has developed two separate frameworks to support patients with chronic and rare diseases: the Specified Pediatric Chronic Diseases (SPCD) Program and the Designated Intractable Diseases (DID) System. Although both aim to provide medical and social assistance, they differ in age of eligibility, diseases covered, and administrative procedures. The SPCD Program provides support to individuals under 18 years of age (extendable to 20) with 858 eligible conditions, whereas the DID System, with 348 designated diseases, applies to all ages. These structural discrepancies create a critical policy gap when pediatric patients transition into adulthood. Those whose conditions are not listed under the DID System lose their eligibility for public subsidies, resulting in sudden financial strain and reduced social participation. Additional issues include inconsistencies in diagnostic criteria, limited access to transitional care facilities — currently established in only 12 prefectures — and insufficient family-centered support, especially for siblings acting as young carers. To achieve continuity of care and equity, Japan must harmonize disease definitions and transition criteria, introduce temporary relief measures for non-designated patients, increase the number of Transitional Care Support Centers in regions, and institutionalize family-inclusive assistance. Establishing a seamless policy framework over a patient's life will not only encourage patients' independence but also strengthen the sustainability of Japan's healthcare system in the face of an aging population.

The mitochondrial DNA A3243G variant, located in the MT-TL1 gene encoding tRNA^Leu(UUR), represents one of the most clinically significant pathogenic mitochondrial mutations. This point mutation accounts for approximately 80% of Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like Episodes (MELAS) syndrome cases and is the primary cause of Maternally Inherited Diabetes and Deafness (MIDD) syndrome. The clinical spectrum associated with this mutation ranges from asymptomatic carriers to severe multisystem disease with early mortality. The pathophysiology involves impaired mitochondrial protein synthesis leading to respiratory chain dysfunction, with phenotypic expression determined by heteroplasmy levels and tissue-specific energy demands. Understanding the complex inheritance patterns, genetic bottleneck effects during oogenesis, and heteroplasmy variations is crucial for comprehending the variable clinical presentations observed in affected families. Histological examination reveals characteristic features including ragged-red fibers, cytochrome c oxidase-deficient fibers, and abnormal mitochondrial proliferation. Current therapeutic approaches focus on metabolic support, antioxidant therapy, and management of specific complications, with L-arginine showing promise for stroke-like episodes. However, careful attention to drug safety profiles and potential mitochondrial toxicity is essential in treatment planning. Understanding the diverse clinical manifestations and implementing appropriate screening strategies are crucial for early diagnosis and optimal patient management. This review synthesizes current knowledge regarding the A3243G variant's pathophysiology, clinical features, diagnostic approaches, and therapeutic interventions.

Rare diseases, characterized by low prevalence and high heterogeneity, impose a significant burden on patients and healthcare systems globally. Utilizing clinical data from the Hospital Information System's Patient Discharge Summaries (2015–2023), we analyzed all rare disease inpatient admissions at a major tertiary hospital in Western China. We examined demographic characteristics, classification of disease systems, medical costs, and readmission rate. Among 1086 inpatient admissions identified with rare diseases (mean age: 46.89 ± 18.99 years), diseases of the nervous system (39.69%), the blood and blood-forming organs and certain disorders involving the immune mechanism (18.32%), the musculoskeletal system and connective tissue (10.50%) constituted the top three disease system categories. The number of the top15 diseases accounted for 73.66% of the total number of patients. The top 3 diseases were POEMS syndrome (11.23%), optical neuromyelitis (10.22%), and Castleman disease (7.46%). Hospitalization costs were predominantly composed of diagnostic (ranged from 6.41% to 49.75%) and medication costs (ranged from 12.97% to 46.22%). The 10 highest readmission rates ranged from 42.86% to 95.90%. The rare diseases in this hospital had a large age span, diverse disease types, high hospitalization costs and large individual differences, which was representative to a certain extent, and can provide scientific basis for the diagnosis, treatment, and prevention of rare diseases in Gansu Province and even the northwest region of China.

Prader-Willi syndrome (PWS) is a genetic disorder resulting from the absence of paternal 15q11-q13 alleles and is clinically characterised by pathological obesity, delayed satiety, hyperphagia, decreased muscle mass, and increased fat mass. Dietary management constitutes a key component in the prevention and treatment of obesity in individuals with PWS. This scoping study aimed to identify dietary interventions available for treating obesity among PWS individuals. A systematic search using the six stages of the scoping review methodology proposed by Arksey and O'Malley was conducted across four databases: PubMed, Scopus, EBSCOhost, and Cochrane Library. The inclusion criteria were full-text research articles published in English between 2017 and 2023, involving human participants with PWS, and reporting on dietary interventions for obesity management. Out of 100 articles retrieved, five studies were identified. Two studies described multidisciplinary programs integrating dietary and physical activity components, while three focused exclusively on dietary interventions. The outcomes varied by intervention and study design. Ketogenic diets and multidisciplinary programs with exercise often resulted in favourable weight and body fat reduction. However, strict diets like the modified Atkins faced adherence challenges and frequent weight regain. Multidisciplinary, supervised programs result in higher adherence and more effective weight management, with body mass index near normal. In conclusion, although research in this area remains limited, current evidence suggests that both dietary and multidisciplinary interventions have the potential to support obesity management in individuals with PWS.