Table 1.

Transition strategy summaries from four European inherited metabolic disease centres.

Centre	Salford Royal NHS Foundation Trust, Salford, UK	Research Center for Children's Health, Moscow, Russia	Vall d'Hebron University Hospital, Barcelona, Spain	HELIOS Dr. Horst Schmidt Kliniken, Wiesbaden, Germany
Planning and preparation
Patient age at start of transition (years)	16–17 (the centre is aiming to reduce this to 14–15, and to start transition education at 12)	17	16–17	NA – patients officially remain under paediatric care, but may start visits with the adult care clinician at age 14
Length of transition	1–2 years, depending on comorbidities, such as neurological deterioration, as well as hospital admissions, newly emerging symptoms, and the patient's capacity to manage the disease	<6 months, and patients formally transferred over a 2-week period	1–2 years, depending on active symptoms, planned surgeries and the patient's capacity to manage the disease	NA
Patient understanding of disease and responsibilities	Assessed during a 1:1 appointment with a metabolic nurse, during which transition passport and ‘Ready Steady Go’ documents are introduced	Assessed at routine appointments	Assessed during the initial transition appointment with a metabolic adult care clinician	Assessed at routine appointments
Transition documents/websites (supplementary material)	Transition passport •Explains transition •Records medical details	Website details for paediatric and adult hospitals	Information on the adult care setting	Website details for HELIOS Dr. Horst Schmidt Kliniken and Society for Mucopolysaccharidoses
	Ready Steady Go •Assesses readiness for transfer to adult care
	Leaflets •Transition plans •Parent/carer •Mental capacity
Referral to adult care system	Paediatric teams provide adult care services with a list of patients who are at an appropriate age to start transition, and circulate referral letters for the transition clinic	Paediatric teams contact adult care teams when patients are 17	Paediatric teams refer patients to adult care teams at the age of 16	NA
Implementation
Transition coordinator(s)	Administrative team and nurse	Paediatric team	Paediatric and adult care metabolic clinicians	Paediatrician and adult care clinicians, with administrative support and a nurse
Core transition team members	Adult and paediatric metabolic specialist nurses	Paediatric treating clinician	Paediatric metabolic team	Rare disease paediatrician
	Metabolic consultant	Adult treating clinician	Adult metabolic treating clinician	Rare disease adult care clinician
	Learning disabilities nurse	Infusion nurse	Psychologist
	Adult metabolic dietician	Psychologist
	Physiotherapist
	Paediatric psychologist
Transition appointments	Held in a transition clinic every 6 months until patient is ready to transfer to the adult care team	Held during routine 6-monthly appointments	Patient attends transition appointments every 4–6 months, until ready to transfer to adult care team	Patients transitioned to adult care clinician working within the same paediatric setting, with appointments every 6–12 months
	Transition clinic held in two locations to allow flexibility for attending patients		Patients sequentially transferred from paediatric to adult care specialists, depending on symptoms	No formal transition clinic
Assessment of readiness for transfer to adult care	Ready Steady Go documents	Disease management and required follow-up under adult care discussed with patient	Transition checklist	Assessed by clinicians
Transfer of medical records from paediatric to adult care teams	Coordinated by administrative team	Prior to transfer, a full medical examination is conducted and details are provided to the adult care team	Managed by paediatric team and adult care nurses	Paediatric and adult care clinicians work in the same paediatric setting
	Details of medical and surgical procedures, medical requirements, assessments and prescriptions are sent from the paediatric team to the adult metabolic team
			MDT meetings held to evaluate symptom severity throughout transition
			Records are electronic and so are available to all treating clinicians
Infusion management during transition	Coordinated by home care nurses	Managed by paediatric or adult care teams, based on patient circumstances	Managed by outpatient clinic or transition nurse if the patient is not receiving infusions at home	Continues under paediatric team management
Other information
Regulations and guidelines that govern transition	Patients <16 years cannot be managed by adult care services	Patients <18 years must be managed by a paediatric team	Institutional regulations state that patients >16 years are not to attend paediatric emergency rooms, but may be followed up in outpatient clinics until the age of 18 years, or 20 years in special circumstances	Adult care clinicians may treat paediatric patients, but paediatricians are not usually reimbursed for treating adult patients
	Patients >18 years cannot be managed by paediatricians
		Patients >18 years must be managed by an adult care clinician
				Adult patients can stay in paediatric wards
	Process is aligned with NICE guidelines on ‘Transition from children's to adults’ services for young people using health or social care services' (NG43) [45]
		Russian guidelines for MPS are based on international publications [37,40]
	Mental Capacity Act 2005 adhered to [46]
Situations during which transfer to adult care could be postponed or not undertaken	Patients without mental capacity to manage their health may be transferred to adult care, while their parents or carers retain responsibility for decision-making [46]	None - all patients are transferred to adult care at the age of 18	Parents may continue to attend appointments if the patient lacks capacity to make decisions regarding their health	NA – care continues in a paediatric setting under the management of an adult care clinician
			Transition timings may be altered for patients in advanced disease stages under palliative care, or if surgery or other procedures are already planned in a paediatric setting
	Patients under palliative care may remain under paediatric care >18 years of age
Numbers of patients with MPS transitioned since 2016	Twelve in total: •Five MPS I •Four MPS II •Three MPS IV	Three in total: •One MPS I •One MPS II •One MPS VI	Seven in total: •One MPS I •One MPS II •One MPS IIIA •One MPS IIIB •Two MPS IV •One MPS VII	Twenty-six between the ages of 14 and 18 years: •Five MPS I •Four MPS II •Six MPS III •Five MPS IV •Six MPS VI

MDT, multidisciplinary team; MPS, mucopolysaccharidosis; NA, not applicable; NHS, National Health Service; NICE, National Institute for Health and Care Excellence.