What can pediatricians learn from adult inherited metabolic diseases?

The field of inherited metabolic diseases (IMD) has initially emerged and developed over decades in pediatric departments. Still, today, about 50% of patients with IMD are adults, and adult metabolic medicine (AMM) is getting more structured at national and international levels. There are several domains in which pediatricians can learn from AMM. First, long-term evolution of IMD patients, especially those treated since childhood, is critical to determine nutritional and neuropsychiatric outcomes in adults so that these outcomes can be better monitored, and patient care adjusted as much as possible from childhood. Conversely, the observation of attenuated phenotypes in adults of IMD known to present with severe phenotypes in children calls for caution in the development of newborn screening programs and, more largely, in the interpretation of next-generation sequencing data. Third, it is important for pediatricians to be familiar with adult-onset IMD as they expand our understanding of metabolism, including in children, such as oxysterols and glycogen metabolism. Last, the identification of common molecular and cellular mechanisms in neurodevelopment and neurodegeneration opens the way to synergistic therapeutic developments that will benefit both fields of pediatric and adult medicine. Overall, these observations underline the need of strong interdisciplinarity between pediatricians and adult specialists for the diagnosis and the treatment of IMD well beyond the issues of patient transition from pediatric to adult medicine.

Healthcare Transition in Inherited Metabolic Disorders—Is a Collaborative Approach between US and European Centers Possible?

Inherited metabolic diseases (IMDs) are rare heterogenous genetic conditions. Advanced technology and novel therapeutic developments have led to the improved life expectancy of patients with IMDs. Long-term, they require close surveillance from specialist adult metabolic providers. Healthcare transition (HCT) is the planned, purposeful process of preparing adolescents for adult-centered medical care and has been recognized globally as a necessary component of care for IMDs. Two recent surveys outlined barriers to the HCT in the US and the UK. The limited knowledge of IMDs among adult physicians was one of the barriers. Some work on specialty curriculum has started and aims to improve the structured training and awareness of rare diseases. Other barriers included social and legal aspects of adulthood, social, vocational and educational support for young adults, care fragmentation and insurance coverage. Although various HCT tools are available, they cannot always be standardized for IMDs. Despite the remarkable differences in the healthcare systems and physicians' training, collaboration among metabolic centers is possible. International rare disease alliance may enhance the patients' management via guidelines development and standardized training for adult metabolic providers.

Adults with lysosomal storage diseases in the undiagnosed diseases network

OBJECTIVES

To review the referral and clinical characteristics of adult patients diagnosed with lysosomal storage diseases (LSD) through the Undiagnosed Diseases Network (UDN).

METHODS

Retrospective review of both application and evaluation records for adults admitted to the UDN with a final diagnosis of a lysosomal storage disease.

RESULTS

Ten patients were identified. Final diagnoses included late onset Tay Sachs, attenuated MPS I, MPS IIIA, MPS IIIB, and MPS IIIC. Most patients presented with neurocognitive changes. Prior to referral, all patients had been evaluated by neurology, four patients underwent phenotype specific panel testing that did not include the causative gene, and four patients had non-diagnostic clinical exome sequencing.

CONCLUSIONS

LSDs figure highly in the differential diagnosis of neurometabolic disorders in pediatric onset progressive diseases. In adults, their subtle initial presentations overlap with symptoms of more common disorders and less practitioner awareness may lead to prolonged diagnostic challenges.

Education and training in adult metabolic medicine: Results of an international survey

Adult metabolic medicine (AMM) is an expanding medical subspecialty, due to the increasing number of adult patients with inherited metabolic diseases (IMD). However, a formal training and postgraduate education in this field is not available in the majority of countries. Existing adult metabolic specialists (AMS) come from many different backgrounds. The aim of this survey was to assess the state of play as regards education and training in AMM worldwide. Members of the Society for the Study of Inborn Error of Metabolism adult metabolic group (n = 89) were asked to take part in this survey. Forty-two AMS (47.2%) from 18 different countries completed the questionnaire. The most common specialties were internal medicine (38.1%), endocrinology (26.2%), genetics (21.4%), and neurology (21.4%). Ninety-five percent of respondents considered that practical clinical experience had contributed importantly for their professional development, while only 27% felt the same for formal academic education. The current state of available education and training was judged as generally poor or fair (73% of the respondents). The most suggested ways of improving education and training in AMM were: to facilitate international internships; to implement courses on adult-IMD; and to create a formal academic education. The skills considered most important for AMS were: recognition of signs and symptoms of diseases, knowledge of the available treatments, and ability to perform a correct follow up. In conclusion, worldwide, current available education and training in AMM is considered inadequate. This survey emphasizes the need for development of new, formal training opportunities to improve knowledge, and competence in this rapidly expanding field.