Protein requirements in adults with phenylketonuria and bioavailability of glycomacropeptide compared to an l-amino acid-based product.

Background: Phenylketonuria (PKU) is caused by phenylalanine hydroxylase deficiency. Treatment is primarily a low-Phe diet combined with l-amino acid-based products (l-AA). Protein requirements in adults with PKU have not been directly determined.

Federal Funding for Expensive Drugs for Rare Diseases: How Do We Pick and Choose?

The number of expensive drugs for rare diseases (EDRDs) approved by Health Canada and their contribution to healthcare costs have been rapidly increasing. The federal government has announced a three-year funding commitment of $1.4 billion for EDRDs, but principles need to be developed for how that funding will be allocated, especially in cases where insufficient data are available to guide decision making.

Response to "Canadians Need Improved Access to Drugs for Rare Diseases, Not More Denial".

The comments provided by Rawson and Adams (2023) miss the mark of our articles (Sirrs et al. 2023a, 2023b). We agree that the patient perspective is critical and that patients with "rare diseases have a right to healthcare and have huge unmet needs …" (p.

Expensive Drugs for Rare Diseases in Canada: Time for Action Everywhere and by Everyone.

Expensive drugs for rare diseases pose unique economic, evidentiary and ethical challenges, and these will continue to escalate unless steps are taken urgently to address these challenges. We propose concrete actions that all stakeholders (federal and provincial/territorial governments, patients, healthcare providers, the public and drug manufacturers) could take now as a first step toward enhancing sustainability in the use of innovative (albeit expensive) therapies within our publicly funded healthcare system.

Expensive Drugs for Rare Diseases in Canada: What Value and at What Cost?

There has been explosive growth in the market for expensive drugs for rare diseases (EDRDs). Traditional standards of evidence are not achievable for rare diseases, so lower standards are applied. The price of these drugs is extremely high.

Impact of hematopoietic stem cell transplantation in glycogen storage disease type Ib: A single-subject research design using C-glucose breath test.

Background: Glycogen storage disease type Ib (GSD Ib) is an autosomal recessively inherited deficiency of the glucose-6-phosphate translocase (G6PT). Clinical features include a combination of a metabolic phenotype (fasting hypoglycemia, lactic acidosis, hepatomegaly) and a hematologic phenotype with neutropenia and neutrophil dysfunction. Dietary treatment involves provision of starches such as uncooked cornstarch (UCCS) and to provide prolonged enteral supply of glucose.

Training competencies in adult metabolic medicine: A survey of working adult metabolic medicine physicians.

The rapid expansion of the number of adult patients with inherited metabolic diseases (IMDs) has created demand for physicians with expertise in the field of adult metabolic medicine (AMM). Unfortunately, existing accredited training programs in this field are rare, and training programs in pediatric metabolic medicine cannot fully meet the needs of AMM physicians as the types of patients and the problems they face are different in the adult setting. We surveyed a group of working practitioners in AMM for input on what medical expert competencies they feel should be included as part of training programs in AMM.

Development of minimally invasive C-glucose breath test to examine different exogenous carbohydrate sources in patients with glycogen storage disease type Ia.

Background: Glycogen storage disease type Ia (GSD Ia) is an autosomal recessive disorder caused by deficiency of glucose-6-phosphatase (G6Pase), resulting in fasting hypoglycemia. Dietary treatment with provision of uncooked cornstarch (UCCS) or a novel modified cornstarch () is available to treat hypoglycemia, yet choice of carbohydrate to achieve a desirable glycemic control is debated.C-glucose breath test (C-GBT) can be used to examine glucose metabolism from different carbohydrate sources via CO in breath.

The Safety of Agalsidase Alfa Enzyme Replacement Therapy in Canadian Patients with Fabry Disease Following Implementation of a Bioreactor Process.

Background And Objective: Fabry disease, an X-linked lysosomal storage disorder characterized by absent or reduced alpha-galactosidase activity, is a lifelong disease that impairs patients' quality of life. Patients with Fabry disease have a considerably shortened lifespan, with mortality being mainly due to renal failure, cardiovascular disease, or cerebrovascular disease. Enzyme replacement therapy with agalsidase alfa has been shown to attenuate the renal, cardiovascular, and neuropathic disease progression associated with Fabry disease.

Independent Registries Are Cost-Effective Tools to Provide Mandatory Postauthorization Surveillance for Orphan Medicinal Products.

Objectives: Orphan medicinal products (OMPs) often receive market authorization under conditions imposed by regulators for ongoing postauthorization surveillance (PAS) to answer questions that remain at the time of market entry. This surveillance may be provided through industry-funded registries (IFRs). Nevertheless, data in these registries may not be of sufficient quality to answer these questions and may not always be accessible for regulatory review.

Registries for orphan drugs: generating evidence or marketing tools?

Independent disease registries for pre-and post-approval of novel treatments for rare diseases are increasingly important for healthcare professionals, patients, regulators and the pharmaceutical industry. Current registries for rare diseases to evaluate orphan drugs are mainly set up and owned by the pharmaceutical industry which leads to unacceptable conflicts of interest. To ensure independence from commercial interests, disease registries should be set up and maintained by healthcare professionals and patients.

High rate of hypertension in patients with m.3243A>G MELAS mutations and POLG variants.

Animal studies suggest that decreased vascular mitochondrial DNA copy number can promote hypertension. We conducted a chart review of blood pressure and hemodynamics in patients with either mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS, n = 36) or individuals with variants in the mitochondrial DNA polymerase gamma (POLG, n = 26). The latter included both pathogenic variants and variants of unknown significance (VUS).

Management of mitochondrial diabetes in the era of novel therapies.

Mitochondrial disorders refer to the complex group of conditions affecting energy metabolism. A number of mitochondrial disorders can lead to the development of diabetes mellitus, and mitochondrial diabetes is thought to account for up to 3% of all diabetes mellitus cases. Depending on the degree of preservation of beta cell secretory capacity and peripheral muscle insulin sensitivity, the phenotype of mitochondrial diabetes may resemble that of type 1 or type 2 diabetes.

Brain MRI features and scoring of leukodystrophy in adult-onset Krabbe disease.

Objective: To perform a systematic analysis and scoring of brain MRI white matter hyperintensities (WMH) in adult-onset Krabbe disease.

Methods: We retrospectively collected basic clinical data and the first available brain MRI from patients with confirmed Krabbe disease with first clinical manifestations beyond 10 years of age. Data were obtained from our reference center for lysosomal diseases (n = 6) and from contacted authors of published articles describing patients with adult-onset Krabbe disease (n = 15).

Lessons from lung transplantation: Cause for redefining the pathophysiology of pulmonary hypertension in gaucher disease.

Background: Gaucher disease type 1 (GD1) is a lysosomal storage disease rarely resulting in end stage pulmonary hypertension (PH) and interstitial lung disease. There have only been two previous case reports of patients with GD1 receiving lung transplants.

Case Presentation: We report a case of successful bilateral sequential lung transplantation in a patient with end-stage GD1-related PH.

A mitochondrial DNA D loop insertion detected almost exclusively in non-replicating tissues with maternal inheritance across three generations.

Muscle biopsy identified a possibly pathogenic, mitochondrial DNA D-loop insertion, in each of 5 family members from two generations, that was otherwise undetectable in most other tissues. The tissue specific regulation of heteroplasmy is reflected in an age related increase in muscle heteroplasmy level, across the pedigree. This latter finding is in keeping with previous reports (e.

Salivary serotonin does not correlate with central serotonin turnover in adult phenylketonuria (PKU) patients.

Introduction: Phenylketonuria (PKU) is an inborn error of metabolism associated with an increased risk of behavioural and mood disorders. There are currently no reliable markers for monitoring mood in PKU. The purpose of this study was to evaluate salivary serotonin as a possible non-invasive marker of long-term mood symptoms and central serotonin activity in patients with PKU.

Prolonged granulocyte colony stimulating factor use in glycogen storage disease type 1b associated with acute myeloid leukemia and with shortened telomere length.

Glycogen storage disease (GSD) type 1 is a rare autosomal recessive inherited condition. The 1b subtype comprises the minority of cases, with an estimated prevalence of 1 in 500,000 children. Patients with glycogen storage disease type 1b are often treated with granulocyte colony stimulating factor (G-CSF) for prolonged periods to improve symptoms of inflammatory bowel disease (IBD) and in the face of severe neutropenia to decrease risk of infection.

Consensus clinical management guidelines for Niemann-Pick disease type C.

Niemann-Pick Type C (NPC) is a progressive and life limiting autosomal recessive disorder caused by mutations in either the NPC1 or NPC2 gene. Mutations in these genes are associated with abnormal endosomal-lysosomal trafficking, resulting in the accumulation of multiple tissue specific lipids in the lysosomes. The clinical spectrum of NPC disease ranges from a neonatal rapidly progressive fatal disorder to an adult-onset chronic neurodegenerative disease.