Learn more about metabolic diseases
What are metabolic diseases?
Metabolic diseases are hereditary. A person is born with the disease. There are an estimated 1,450 different metabolic diseases, 800 of which have been identified in Belgium. The majority of these pathologies are rare, even ultra-rare. It is estimated that there are between 2,000 and 2,500 people in Belgium with a rare disease. Metabolic diseases are the result of a defective or missing enzyme in cells. The characteristics and symptoms of the disease depend on the enzyme‘s normal function in the body.
What is metabolism?
Our food is made up of different nutrients: proteins, carbohydrates, fats, vitamins, and minerals. Food is broken down in the stomach and intestines, and the nutrients are absorbed by the cells. This is called digestion. The stomach and intestines contain enzymes that aid in digestion. When these enzymes are defective or absent, problems occur, and nutrients are not absorbed. They are eliminated through the stool. However, the metabolic process only begins in the cells. Nutrients are further broken down and processed for the development of tissues such as muscles, bones, and organs, and the release of energy. Enzymes are essential for metabolism. They are produced within the cells themselves. When a cell does not produce an enzyme properly, nutrients are not processed or broken down properly. This is called a metabolic disease.
Enzymes
Enzymes are proteins that are produced by the body itself. Enzymes are involved in all kinds of processes in the cell. They can cut off or attach certain elements of a substance, so that another substance is created. The processing of substances takes place in a number of steps. A different enzyme is needed for each step in the processing. There are thousands of enzymes at work in our body. If such an enzyme does not work properly or is missing, such a process will fail. Too many harmful substances are produced, or too few substances that the body desperately needs. The consequences are different for each enzyme defect, and therefore for each metabolic disorder.
Symptoms
Every metabolic disorder manifests itself in a different way. Symptoms can arise shortly after birth, but also in the years after or even in adulthood. There is a range of possible symptoms, such as developmental delay, growth retardation, fatigue, coma and epilepsy.
With these complaints, the patient comes to a (family) doctor. If the (family) doctor suspects that a metabolic disorder is the underlying cause of the complaints, blood or urine is sent to a metabolic laboratory. In such a laboratory, research is done on specific substances in the blood, urine or cerebrospinal fluid. It often takes some puzzling before a doctor can make the diagnosis.
The course of the diseases varies greatly. There are metabolic diseases with which someone can grow into a normal adult, if for example one sticks to the diet. A number of diseases have both mild and serious forms. There are also metabolic diseases with an erratic course.
In addition, a number of metabolic diseases have a progressive course. This means that the symptoms become worse and the patient deteriorates. The disease can cause serious limitations and sometimes have such serious symptoms that the patient dies prematurely.