Cystinosis

Cystinosis is an inherited disease resulting in poor growth and kidney failure. There is no known cure for cystinosis, although kidney transplantation may help the renal failure and prolong survival. Both the kidney damage and growth failure are thought to be due to the accumulation of the amino acid cystine within the cells of the body. The cystine storage later damages other organs besides the kidneys, including the thyroid gland, pancreas, eyes, and muscle. The drug cysteamine (Cystagon; ProCysBi) is an oral medication given to patients with cystinosis prior to kidney transplantation. The drug works by reducing the level of cystine in the white blood cells and muscle tissue. The drug may also decrease levels of cystine in the kidneys and other tissues. This study has several goals: 1. Long-term surveillance of cysteamine treated patients. 2. Detection of new non-kidney complications of cystinosis. 3. Maintenance of a patient population for genetic testing (mutational analysis) of the cystinosis gene.\<TAB\>

This European observational cohort follows patients with cystinosis, a rare lysosomal storage disease caused by CTNS mutations leading to cystine accumulation and multisystem involvement. It aims to describe the long-term clinical course under current treatments, focusing on renal and extra-renal complications, survival, and quality of life. It also evaluates treatment effects and explores biomarkers, including inflammatory markers, with biobanking for future research.

Cystinosis is a generalized lysosomal storage disease with a reported incidence of about 1:180,000 live births. There are estimated 110-140 cases in France (approximately 500 in Western Europe). The disease is caused by mutations in the CTNS gene coding for cystinosin, a lysosomal carrier protein. The lysosomal cystine accumulation leads to cellular dysfunction in many organs. The first symptoms start at about 6 months of age. In the absence of specific therapy, end stage renal disease occurs between 6 and 12 years of age. Survival beyond this age is associated with the development of extra-renal complications. Renal transplantation and the availability of cystine-depleting medical therapy, cysteamine (EU/1/97/039/001, EU/1/97/039/003), have radically altered the natural history of cystinosis. Cystinosis is a good example of a "paediatric" disease where patients now survive into adolescence and adulthood. These individuals have complex, multisystem problems that require on-going care. Despite some progress in recent years there are still significant limitations in the knowledge of diagnostic and therapeutic procedures. A first European registry was launched in 2011, using the CEMARA application developed by the Banque Nationale de Données Maladies Rares (BNDMR, CNIL authorisation number: 1187326), allowing the collection of data from France, Belgium and Italy. The objective of the current study is to translate this database into a cohort study that will allow and facilitate the collection of a wider range of data including clinical, and personal data such as quality of life data, from an increased number of European countries, improve the monitoring, data-management and analysis of the data, offer the possibility for patients to actively participate to and benefit from the study by developing a module in which patients will enter their own data on quality of life with a direct feed-back on the general results. This project is a unique opportunity for building a consensual European academic cohort not based on company driven, "drug-oriented" objectives. The cohort will collect clinical details to analyse patient outcomes thus providing audit of patient care \& clinical effectiveness. It will be possible, through the cohort, to indicate where improvements need to be made and ultimately improve care to the highest standards.

Cystinosis is a monogenic autosomal recessive lysosomal storage disease with complete penetrance, caused by a biallelic mutation in the CTNS gene (17p13.2) encoding cystinosin, a ubiquitous membrane protein whose role is to clear cystine into the cytosol. Its dysfunction in patients with cystinosis leads to systemic accumulation of cystine, an oxidised dimer of cysteines linked by a disulphide bridge, in the lysosomal space, and irreversible cellular dysfunction. Renal damage is at the forefront, with Fanconi syndrome (proximal tubulopathy) and chronic renal failure developing early in childhood/adolescence. There are also multi-systemic disorders, notably endocrine and ophthalmological. Cysteamine is an amino thiol which reduces the level of intra-lysosomal cystine by breaking the disulphide strands of cystine, giving two cysteines which complex with cysteamine to leave the lysosome. Since the late 1980s, there has been an immediate-release form of the drug, which has considerably improved overall patient survival despite having a major impact on quality of life. This improvement in survival has also led to the emergence of later complications that were not previously observed. This musculoskeletal complication (described in an international consensus in 2019), known as 'CMBD' for Cystinosis Metabolic Bone Disease, may be explained at least in part by an intrinsic defect in the osteoblast and osteoclast that contribute to the human bone phenotype. This intrinsic bone defect appears to be responsible for premature ageing. In order to identify potential future therapeutic targets for CMBD, it is essential to gain a better understanding of the underlying pathophysiological mechanisms. To better understand premature aging in extra-renal damage in cystinosis, it seems relevant to investigate energy metabolism dysfunction, particularly mitochondrial dysfunction.

CoRDS, or the Coordination of Rare Diseases at Sanford, is based at Sanford Research in Sioux Falls, South Dakota. It provides researchers with a centralized, international patient registry for all rare diseases. This program allows patients and researchers to connect as easily as possible to help advance treatments and cures for rare diseases. The CoRDS team works with patient advocacy groups, individuals and researchers to help in the advancement of research in over 7,000 rare diseases. The registry is free for patients to enroll and researchers to access. Visit sanfordresearch.org/CoRDS to enroll.

Cystinosis is a rare congenital, inherited metabolic disorder that results in the storage of cystine in the cells of many organs of the body. In the infantile nephropathic form of the disease, only the kidney is initially affected by a loss of function, which progresses if untreated and ends in terminal renal failure by early school age. With the prolonged survival of patients due to medication and renal replacement therapy, further loss of function may occur during the course of the disease, especially in the eyes, muscles, endocrine organs and central nervous system. The quality of life of children with cystinosis is an under-researched topic. The results of the studies available so far show that the young patients and their families report a reduced quality of life and sometimes behavioral problems. To date, there are no disease specific patient reported outcome measures (PROMs) to measure the quality of life of patients with cystinosis. The aim of the study is to develop a PROM for this target group in several languages (German, English, Spanish and French) from different countries (Germany, United States, Spain, France). The PROM will focus on quality of life and will be developed for children, adolescents, and young adults including parent-report of parents with children aged 0 to 26 years.

The goal of this National Registry is to is to collect information from patients with rare kidney diseases, so that it that can be used for research. The purpose of this research is to: * Develop Clinical Guidelines for specific rare kidney diseases. These are written recommendations on how to diagnose and treat a medical condition. * Audit treatments and outcomes. An audit makes checks to see if what should be done is being done and asks if it could be done better. * Further the development of future treatments. Participants will be invited to participate on clinical trials and other studies. The registry has the capacity to feedback relevant information to patients and in conjunction with Patient Knows Best (Home - Patients Know Best), allows patients to provide information themselves, including their own reported quality of life and outcome measures.

This is a single center, non-randomized, non-controlled open-label phase 1b/2a trial of performing sequential αβdepleted-HSCT and KT in patients requiring KT to prevent kidney rejection post-KT, in the absence of any post-KT immunosuppression, to abrogate the need for lifelong immunosuppression, the risk of chronic rejection and, ultimately, the need for repeated transplantation.

In Germany parents of newborns are offered newborn screening (NBS) for 17 congenital diseases as a standard benefit of statutory health insurance. NBS in Germany is voluntary. Cystinosis and hyperoxaluria are very rare diseases. They are inherited autosomal-recessively. Neither disease can be detected by the methods established in routine NBS. However, common genetic mutations are known for both diseases. The aim of the study is to provide a scientific basis for molecular genetic NBS for cystinosis and primary hyperoxaluria (PH). Specifically, the study will investigate whether the inclusion of these diseases into general NBS should be recommended. By observing the identified infants in comparison to patients symptomatically diagnosed outside of the pilot project, it will be determined whether and to what extent early diagnosis and therapy lead to a more favorable prognosis. The screening laboratory Hannover, Germany is involved in the project. Hospitals that send their dry blood spot cards for routine NBS to Hannover are offered participation in the project. Parents who want to participate receive an additional information sheet. A parent and the attending physician sign the information sheet as documentation of informed consent, which allows data transfer and patient referral to a specialist in case of a positive result. Molecular genetic screening in the pilot project is performed from the same dry blood spot card used for routine NBS. In both diseases, testing is performed for 2 known mutations: In cystinosis for the 2 mutations most common in Germany, and in PH for the most common mutation in infantile hyperoxaluria (PH1) and in Europe (PH3). Normal findings are not communicated to the parents, which may contact the laboratory to ask for them. Parents of newborns with two mutations in the cystinosis gene are immediately informed about the disease by a physician. Further diagnostics to confirm the disease are organized close to home. In contrast, parents of newborns with only one mutation in one of the two hyperoxaluria genes are informed. They are asked to send spot urines of the newborn to the hyperoxaluria center. Only if these are abnormal, further evaluation will be performed. The study started on 15.03.2022. The aim is to screen 200,000 newborns until 2025. If the benefit of early diagnosis and therapy can be shown, an application for inclusion of a NBS for these two diseases in the routine NBS program will be submitted to the German government.