Asia-Pacific Consensus Recommendations on X-Linked Hypophosphatemia: Diagnosis, Multidisciplinary Management, and Transition From Pediatric to Adult Care.

X-linked hypophosphatemia (XLH) is a rare, inherited, multisystem disorder characterized by hypophosphatemia that occurs secondary to renal phosphate wasting. Mutations in PHEX gene (located at Xp22.1) in XLH alter bone mineral metabolism, resulting in diverse skeletal, dental, and other extraskeletal abnormalities that become evident in early childhood and persist into adolescence and adult life. XLH impacts physical function, mobility, and quality of life, and is associated with substantial socioeconomic burden and health care resource utilization. As the burden of illness varies with age, an appropriate transition of care from childhood and adolescence to adulthood is necessary to meet growth-related changes and minimize long-term sequelae of the condition. Previous XLH guidelines that encompassed transition of care have focused on Western experience. Regional differences in resource availability warrant tailoring of recommendations to the Asia-Pacific (APAC) context. Hence, a core expert panel of 15 pediatric and adult endocrinologists from nine countries/regions across APAC convened to formulate evidence-based recommendations for optimizing XLH care. A comprehensive literature search on PubMed using MeSH and free-text terms relevant to predetermined clinical questions on diagnosis, multidisciplinary management, and transition of care of XLH revealed 2171 abstracts. The abstracts were reviewed independently by two authors to shortlist a final of 164 articles. A total of 92 full-text articles were finally selected for data extraction and drafting the consensus statements. Sixteen guiding statements were developed based on review of evidence and real-world clinical experience. The GRADE criteria were used to appraise the quality of evidence supporting the statements. Subsequently, a Delphi technique was utilized to rate the agreement on statements; 38 XLH experts (15 core, 20 additional, 3 international) from 15 countries/regions (12 APAC, 3 EU) participated in the Delphi voting to further refine the statements. Statements 1-3 cover the screening and diagnosis of pediatric and adult XLH; we have defined the clinical, imaging, biochemical, and genetic criteria and raised red flags for the presumptive and confirmatory diagnosis of XLH. Statements 4-12 tackle elements of multidisciplinary management in XLH such as therapeutic goals and options, composition of the multidisciplinary team, follow-up assessments, required monitoring schedules, and the role of telemedicine. Treatment with active vitamin D, oral phosphate, and burosumab is discussed in terms of applicability to APAC settings. We also expound on multidisciplinary care for different age groups (children, adolescents, adults) and pregnant or lactating women. Statements 13-15 address facets of the transition from pediatric to adult care: targets and timelines, roles and responsibilities of stakeholders, and process flow. We explain the use of validated questionnaires, desirable characteristics of a transition care clinic, and important components of a transfer letter. Lastly, strategies to improve XLH education to the medical community are also elaborated in statement 16. Overall, optimized care for XLH patients requires prompt diagnosis, timely multidisciplinary care, and a seamless transfer of care through the coordinated effort of pediatric and adult health care providers, nurse practitioners, parents or caregivers, and patients. To achieve this end, we provide specific guidance for clinical practice in APAC settings. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Current diagnosis and management of mucopolysaccharidosis VI in the Asia-Pacific region.

INTRODUCTION: Mucopolysaccharidosis (MPS) type VI (Maroteaux-Lamy syndrome) is a clinically heterogeneous lysosomal storage disorder. It presents significant diagnostic and treatment challenges due to the rarity of the disease and complexity of the phenotype. As information about MPS VI in Asia-Pacific countries is limited, a survey was conducted to assess current practices for diagnosis and management of MPS VI in this region. The participants were selected based on their experience in diagnosing and managing MPS patients. METHODS: The survey comprised 29 structured quantitative or qualitative questions. Follow-up consultations were undertaken to discuss the data further. RESULTS: Thirteen physicians from eight countries or regions (Australia, China, Hong Kong, Japan, Malaysia, Philippines, Taiwan and Thailand) were surveyed. At the time of the survey twenty-two patients with MPS VI were directly treated by the respondents and most (~80%) had rapidly progressing disease. A wide range of medical specialists are involved in managing patients with MPS VI, the most common being orthopedic surgeons, pediatricians and geneticists. The availability/accessibility of diagnostic tools, therapies and national insurance coverage vary greatly across the countries/regions and, in some cases, between different regions within the same country. Currently, there are national MPS management groups in Australia and Japan. Australia, Taiwan and Hong Kong have local guidelines for managing MPS and local MPS registries are available in Australia, Taiwan, and Japan. CONCLUSIONS: This survey highlights differences in the diagnosis and management of MPS VI between Asia-Pacific countries/regions. Important barriers to advancing the identification, understanding and treatment of MPS VI include the paucity of epidemiological information, limited access to laboratory diagnostics and therapies, low disease awareness, and a lack of monitoring and treatment guidelines. There is a clear need to facilitate communications between physicians and establish regional or national disease registries, a multidisciplinary referral network, and a centralized diagnostic and management framework.

Features of partial remission in children with type 1 diabetes using the insulin dose-adjusted A1c definition and risk factors associated with nonremission.

PURPOSE: We sought to evaluate features of partial remission (PR) in children with type 1 diabetes mellitus (T1DM) using the insulin-dose adjusted A1c (IDAA1c) definition and to identify risk factors associated with nonremission. METHODS: Medical records of patients with newly diagnosed T1DM between January 1, 2008, and June 30, 2018, were retrospectively reviewed. Hemoglobin A1c (HbA1c) readings and insulin total daily doses (TDDs) of each patient at each follow-up visit were obtained with IDAA1c values calculated. PR was defined as an IDAA1c score of 9 points or less within 6 months of diagnosis. The trends of HbA1c and TDD within 2 years after diagnosis were compared between remitters and nonremitters. Factors that may predict the occurrence of PR were studied, with their relative risks of nonremission calculated. RESULTS: PR occurred in 26 patients (45.6%), including 8 girls and 18 boys, with a median duration of 8 months. The frequency of remission in male patients was significantly higher (P=0.002) and the relative risk of female sex with nonremission was 2.20 (95% confidence interval [CI], 1.24-3.91), which remained significant when adjusted by multivariate regression modeling. The initial HbA1c level at diagnosis was also significantly higher in the nonremission group (P=0.029), with a relative risk of 1.12 (95% CI, 1.01-1.25). Both HbA1c (P=0.012) and TDD (P=0.006) were significantly lower within 2 years after diagnosis among remitters than in nonremitters. TDD was significantly lower in male patients (P=0.029) during the same period, while there was no significant difference in HbA1c level between male and female patients (P=0.163). CONCLUSION: Both the initial HbA1c level at diagnosis and sex were factors associated with the occurrence of PR. Female sex was an independent risk factor of nonremission, likely resulting from a higher insulin requirement in female T1DM patients.

Medical issues among children and teenagers with Down syndrome in Hong Kong.

UNLABELLED: We examined the prevalence of medical problems in children and teenagers with Down syndrome in Hong Kong. METHODS: Children with Down syndrome receiving care from seven regional hospitals were included and their hospital records were reviewed. A total of 407 patients, aged between 0.06 and 17.16 years were included. Cardiovascular problems were observed in 216 (53%), endocrine problems in 111 (27%), gastrointestinal problems in 46 (11%), haematological problems in 18 (4%), neurological problems in 27 (7%), sleep problems in 36 (9%), skeletal problems in 56 (14%), visual problems in 195 (48%) and auditory problems in 137 (34%). CONCLUSIONS: The prevalence of medical problems was high in children and teenagers with Down syndrome in Hong Kong and similar to previous findings elsewhere. Future studies on the local prevalence of medical problems in the adult population with Down syndrome would help to define their medical needs.

A novel nonsense mutation in the LPL gene in a Chinese neonate with hypertriglyceridemia.

BACKGROUND: Lipoprotein lipase (LPL) deficiency is a rare autosomal recessive disorder characterized by hypertriglyceridemia. The genetic defect lies in a mutation of the LPL gene. METHODS: A Chinese neonate with non-consanguineous parents was incidentally found to have hypertriglyceridemia. Mutation in her LPL gene was screened by using polymerase chain reaction and direct DNA sequencing. RESULTS: Homozygous missense mutations (L252V) were detected in the LPL gene of the patient. A novel nonsense mutation (C27X) was also identified. CONCLUSION: Our finding supports L252V mutation in the LPL gene is a common mutation in Chinese with familial hyperchylomicronemia syndrome. DNA-based diagnosis in this syndrome is definitive. It saves the need for heparin-infusion test, which carries the risk of hemorrhage, and the measurement of LPL activity, which is tedious and is not widely available.