Inborn Errors of Metabolism

Methylmalonic acidemia (MMA), one of the most common inborn errors of organic acid metabolism, is heterogeneous in etiology and clinical manifestations. Affected patients with cblA, cblB and mut classes of MMA are medically fragile and can suffer from complications such as metabolic stroke or infarction of the basal ganglia, pancreatitis, end stage renal failure, growth impairment, osteoporosis, and developmental delay. The frequency of these complications and their precipitants remain undefined. Furthermore, current treatment protocol outcomes have continued to demonstrate substantial morbidity and mortality in the patient population. Increasingly, solid organ transplantation (liver, and/or kidney) has been used to treat patients. Disordered transport and intracellular metabolism of vitamin B12 produces a distinct group of disorders that feature methylmalonic acidemia as well as (hyper)homocysteinemia. These conditions are named after the corresponding cellular complementation class - (cblC, cblD, cblF, cblJ and cblX) - and are also heterogenous, clinically and biochemically. The genetic disorders underlying cblE and cblG feature an isolated impairment of the activity of methionine synthase, a critical enzyme involved in the conversion of homocysteine to methionine and these disorders feature (hyper)homocysteinemia. Lastly, a group of patients can have increased methylmalonic acid and/or homocysteine in the blood or urine caused by variant(s) in recently identified (ACSF3) and unknown genes. In this protocol, we will clinically evaluate patients with methylmalonic acidemia and cobalamin metabolic defects. Routine inpatient admissions will last up to 4-5 days and involve urine collection, blood drawing, ophthalmological examination, radiological procedures, MRI/MRS, skin biopsies in some, and developmental testing. In a subset of patients who have or will receive renal, hepato- or hepato-renal transplants or have an unusual variant or clinical course and have MMA, a lumbar puncture to examine CSF metabolites will be performed. In this small group of patients, CSF metabolite monitoring may be used to adjust therapy. The study objectives will be to further delineate the spectrum of phenotypes and characterize the natural history of these enzymopathies, query for genotype/enzymatic/phenotype correlations, search for new genetic causes of methylmalonic acidemia and/or homocysteinemia, identify new disease biomarkers and define clinical outcome parameters for future clinical trials. The population will consist of participants previously evaluated at NIH, physician referrals, and families directed to the study from clinicaltrials.gov as well as the Organic Acidemia Association, Homocystinuria Network America and other national and international support groups. Most participants will be evaluated only at the NIH Clinical Center. However, if the NIH team decides that a patient under the age of 2 years is a candidate subject for this research protocol, that patient may enroll at the Children's National Medical Center (CNMC) site, pending approval by Dr Chapman, the Principal Investigator of the CNMC location Individuals may also enroll in the tissue collection only part of the study at the UPMC Children's Hospital of Pittsburgh or share medical history and clinical data via telemedicine visits remotely. Outcome measures will largely be descriptive and encompass correlations between clinical, biochemical and molecular parameters....

The major morbidities of allogeneic hematopoietic stem cell transplant (HSCT) using donors that are not human leukocyte antigen (HLA) matched siblings are graft vs host disease (GVHD) and life- threatening infections. T cell receptor alpha beta (TCRαβ) T lymphocyte depletion and CD19+ B lymphocyte depletion of alternative donor hematopoietic stem cell (HSC) grafts is effective in preventing GVHD, but immune reconstitution may be delayed, increasing the risk of infections. The central hypothesis of this study is that an addback of CD45RO memory T lymphocytes, derived from a fraction of the original donor peripheral stem cell product depleted of CD45RA naïve T lymphocytes, will accelerate immune reconstitution and help decrease the risk of infections in TCRab/CD19 depleted PSCT.

The goal of this protocol is to expand access for patients who lack a fully HLA (Human leukocyte antigen) matched sibling donor and who are candidates for allogeneic hematopoietic stem cell transplant (HSCT). These patients have a serious or immediately life-threatening disease for which HSCT is indicated. These patients are not eligible for other Children's Hospital of Philadelphia IRB approved protocols that utilize CliniMACs technology for T depletion.

The goal of this observational study is to create a single macro registry system with data collection on common clinical features, grouping the different rare diseases (RD). Moreover, the specific goals are to generate an alert system for possible cases of RD with data from the electronic medical record, to describe the occurrence of RD in the evaluated population, to characterize the population, to describe patterns of diagnosis and treatment of RD present at the time, and to explore patient-reported outcomes.

Assessment of growth and development of children with inborn errors of metabolism in Assiut Governorate

Main aims of this project are * To assess the baseline status-quo of transition and "fitness for transfer" in terms of information about the adult centre and team, organisational and practical skills (blood sampling and sending, how to make an appointment etc.), disease- and treatment-related knowledge, health-related quality of life (HrQoL), and self-efficacy in adolescnets with inborn errors of metabolism. Biochemical or physical parameters as appropriate for the respective diseases from 12 months before are documented. * To provide targeted, structured intervention modules (using available and, if necessary, adapted materials). * To measure the effects of these interventions on information about adult services short-term (within a month) and to re-assess all other baseline status-quo parameters long-term (6 and 12 months later). Psychological assessments will be complemented by biochemical or physical parameters as appropriate for the respective diseases and indicative for transition success.

The primary goal of this study is to establish a biobank of dried blood spots and urines from a large control cohort and collect several cohorts as large as possible of patients affected or suspected of being affected by rare diseases (mainly hereditary metabolic diseases) or by autism spectrum disorders. A metabolomic database using a high-resolution mass spectrometer (i.e. the "Device") will be generated and specific biomarkers for the diseases will be confirmed or uncovered. The ultimate goal is to facilitate and improve the diagnosis and screening of the patients affected by these disorders, but also to improve the knowledge about the biochemical mechanisms involved over the course of the selected pathologies. High-resolution mass spectrometry allows the measurement of thousands of metabolites in a single analysis. The current biochemical tests used for the diagnosis of hereditary metabolic diseases are only using a combination of maximum a few dozens of biomarkers in one analysis. Objectives Unravel new biomarkers for diagnosis (+/- explore the altered pathways…) Uncover and/or validate newborn screening biomarkers through retrospective analysis of preserved newborn DBS from confirmed patients (useful for first or second tier biochemical NBS testing!) Validation of LC-MS qTOF for metabolomics screening as first line diagnostic test (thousands of metabolites) using diagnostic algorithms (modified z-scores) \& continuous optimization by adding new cases and new controls in the database Generation of a biobank of urines and DBS from rare diseases (IEMs) \& from a large reference population useful for other research applications