Rare diseases

General information regarding rare diseases

By way of example, below are the details of some of the most well-known rare disease are given below:[1][2]

Mucoviscidosis: affects about 1 in 3,000 newborns in Europe and 1 in 5,000 in Belgium. Spinal muscular atrophy: affects about 1 in 30,000 births in Europe. Huntington’s disease: estimated prevalence of 1 in 20,000 to 1 in 10,000 people. Duchenne muscular dystrophy: occurs mainly in boys with a prevalence between 1 in 3,500 and 1 in 9,300 boys. Amyotrophic lateral sclerosis: has a prevalence of about 1 in 20,000, with a slight preponderance of men (ratio of about 1.5 men to 1 woman). Haemophilia: affects 1 in 5,000 boys at birth and 1 in 12,000 persons in the general population.

Most of these diseases are serious, complex genetic disorders that can also be chronic and progressive. No less than 75% of them affect children. Of patients with rare diseases, 30% die before the age of 5 years. In Belgium, it is estimated that more than 660,000 people suffer from a rare disease.

These diseases also have major economic and professional consequences for patients and their families. On average, 36% of patients are obliged to significantly reduce or completely stop carrying out their occupational activities. In 26% of cases, a family member must also give up his or her job to devote himself or herself to caregiving.[3]

In most cases, there is no cure, but treatment of the symptoms can improve the patient’s quality of life and extend their lifespan.

The large number, diversity, and rarity of these diseases create several problems in treating them. On average, it takes 5 years until the correct diagnosis is made. The characteristics of these diseases mean that the expertise needed to treat them cannot possibly be available everywhere in Belgium. Networks with the aim of pooling expertise in the field are therefore particularly important in the case of these diseases.

Rare disease networks in Belgium

Treating rare diseases requires highly specialised care. General practitioners and specialists can refer their patients to one of the 8 hospitals with an accreditation for the function of ‘Rare diseases’. This accreditation guarantees quality of care, diagnostic expertise, specialised multidisciplinary care, access to innovative treatments, and the opportunity to participate in research. The hospitals that have obtained this accreditation are: Cliniques universitaires Saint-Luc, CHU de Liège, UZ Brussel, Hôpital Erasme, UZ Antwerpen, UZ Leuven, UZ Gent as well as the Grand Hôpital de Charleroi in collaboration with the Institute of Pathology and Genetics (IPG).

In Flanders, the “Vlaamse Netwerken Zeldzame Ziekten” (Flemish Networks of Rare Diseases) association was set up in 2017. This structure facilitates the creation of rare diseases networks in Flanders. There are now 23 networks, based on the same disease groups as the European reference networks. Taking part in those networks is voluntary.

European reference networks for rare diseases (ERNs)

The large number of different rare diseases, the rarity of each disease, and its complexity present a major challenge. The expertise needed to treat a disease is not always available, sometimes not even in the patient’s country of residence, and the same is also true of the treatments themselves. The characteristics of these diseases also lead to a lack of resources in healthcare systems: for example, the often (very) high cost of treatment, or the difficulty of conducting research due to the small number of patients and the lack of data and resources. In Europe, an estimated 30 million people suffer from a rare disease.

To meet these challenges, the European Commission, together with EU Member States and Norway, created the European Reference Networks for Rare Diseases, also known as ERNs, in 2017. These are virtual networks that aim to bring together European expertise on rare diseases. There are currently 24 ERNs, each of which specialises in a specific type of disease. Teams of experts from across Europe participate in these networks, which aim to disseminate expertise rather than patients. These networks work on virtual consultations, setting up specific registries, drawing up treatment guidelines, and organising training sessions to share knowledge.

A healthcare provider can call upon the knowledge of expert members of an ERN. The assembled experts will analyse the specific case of the patient. If necessary, additional examinations may be requested and, whenever possible, performed in the patient’s country of residence. The goal of this virtual advisory board is to make the correct diagnosis and suggest the most appropriate treatment. If specialist intervention is needed, efforts are made to ensure that expertise goes to the patient’s country as much as possible and not the other way around. This is not always possible.

This work allows health professionals who previously treated rare and complex cases in isolation to consult their colleagues for a second opinion.

For more information, see https://health.ec.europa.eu/rare-diseases-and-europeanreference-
networks/european-reference-networks_en

^{[1] Source: Sciensano. (2024). Rare diseases. Consulted at https://www.sciensano.be/nl/gezondheidsonderwerpen/zeldzame-ziekten}

^{[2] Source: Orphanet. (2024). Access to aggregated data from Orphanet. Consulted at https://www.orphadata.com.}

^{[3] Source : Rare Diseases and Orphan Drugs Fund (2011). Recommendations and proposals for action for a Belgian Plan for Rare Diseases. Consulted on https://www.departementzorg.be/nl/zeldzame-ziekten-0}