Thanks to this screening, metabolic and hormonal diseases can be verified shortly after birth with the aid of the latest technology.
The ten diseases screened in the laboratory will be listed in particular and briefly described.
If left untreated, this metabolic disease usually leads to serious brain damage in the growing child, who will then require constant care throughout life. However, if the disorder is identified in the first weeks of life and treated with an appropriate diet, the child will be healthy. In cases of PKU, the amino acid phenylalanine, a normal component of all animal and plant proteins, usually absorbed during digestion, cannot be processed properly in the body. This leads to the production of metabolic substances that are poisonous to the brain. A special diet containing low levels of phenylalanine prevents the disease from advancing.
Incidence is about one in 8000 newborns, with varying severity
Hypothyroidism, a congenital underactive thyroid, slows all metabolic functions due to insufficient thyroid hormones, leading to serious impairment of physical and mental development. However, if the lacking hormone is administered in tablet form soon after birth on a daily basis, normal metabolic function is established and healthy childhood development is thus guaranteed.
Hypothyroidism is quite common, affecting one in 3500 newborns.
Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCADD)
MCADD is a congenital disorder affecting the breakdown of fatty acids in adipose tissue. This disease first becomes apparent when the body has to access fat reserves during prolonged periods of fasting, vomiting, diarrhoea or fever – for instance as a result of the minor infections experienced frequently throughout childhood. The effects are drowsiness, nausea, low blood sugar, seizures and coma. If undiagnosed, the first onset frequently leads to death.
However, if appropriate preventative measures are taken (avoiding long periods of fasting and providing a sufficient intake of carbohydrates, especially during infections with fever) the prognosis is excellent.
MCADD affects one in 10,000 newborns.
Newborns suffering from galactosaemia cannot tolerate lactose. A milk-based diet then leads to severe liver, kidney and brain damage, impaired vision and, in some cases, even death. Yet if the disorder is identified in the first days of life and treated with an appropriate diet, the child will remain healthy.
It is treated by strictly avoiding galactose, a component of lactose, which is present in human breast milk, cow’s milk and other foods.
The disorder affects one in 55,000 newborns. There are two other forms of galactosaemia besides the classic variety, but these are rarer and less serious.
Congenital Adrenal Hyperplasia (CAH)
In cases of CAH, the adrenal cortex produces insufficient cortisol. This leads to dangerous crises involving low blood sugar and the loss of salts during infections with fever. There also is an excessive production of male hormones that causes masculine development of the outer genitalia in affected girls. Among affected boys, genitals develop normally, but puberty sets in early, leading to stunted growth and infertility. Therapy is simple: The lacking hormones are administered as tablets. If such treatment begins shortly after birth, CAH causes no damage. The disorder affects one in 9000 newborns.
This disorder causes various types of damage, which may be extremely severe and can even result in the infant’s death. The enzyme biotinidase normally releases the vitamin biotin from its bound form, making it available to the body in its free form. In cases of this illness though, the vitamin is lost. However, biotin is vital for the functioning of various metabolic enzymes.
Here too, early diagnosis and immediate therapy can prevent damage. Treatment of biotinidase deficiency is simple, consisting of the daily intake of one biotin tablet. The disorder is roughly as common as galactosaemia.
Cystic Fibrosis (CF)
CF involves a cellular salt-exchange malfunction, leading to excessively viscous secretions in the airways and pancreas. This causes chronic airway inflammation, stunted growth and serious illness if it remains untreated. Mild variants are also known, which are sometimes not diagnosed until adulthood. With intensive inhalation, chest physiotherapy, and an appropriate diet involving the supplementation of digestive enzymes and fat-soluble vitamins, unnecessary hospitalisation can be avoided and better development is possible. CF is the most common congenital metabolic disease and it affects around one in 3000 newborns.
Glutaric Acidemia Type 1 (GA1)
In cases of this metabolic disorder, the amino acids lysine and tryptophan, normal components of all animal and plant proteins, cannot be processed properly in the body. This leads to the production of metabolic substances that are toxic for the brain. Affected children tend not to have any symptoms as newborns. If left untreated, most children with the condition will have a larger head than normal and over time will suffer from developmental delay, as well as mild movement disorders. Between the ages of 3 months and 3 years, acute metabolic crises occur, often triggered by minor infections, which can lead to permanent movement disorders and severe disability.
GA1 can be managed well with a special diet and by taking l-carnitine supplements. To prevent metabolic crises, even minor infections should be treated as emergencies during the first years of life, meaning inpatient emergency treatment as a precautionary measure.
Maple Syrup Urine Disease (MSUD)
Maple syrup urine disease (also known as MSUD) is a congenital metabolic disorder, in which particular protein components (the so-called amino acids leucine, isoleucine and valine) cannot be properly processed in the body. As a consequence, toxic substances accumulate, which can lead to a very rapid decline in newborns. The occurrence of brain swelling is particularly serious and can cause a coma. If left untreated, this disease can lead to death. There are also mild forms known, which affect patients less significantly. MSUD can be managed well with a special diet. Patients who are diagnosed during new born screening have a good prognosis.
Severe Combined Immunodeficiency (SCID) and Severe T-Cell Lymphopenia
Cases of severe combined immunodeficiency (SCID) and severe T-cell lymphopenia involve a disturbance in the formation of Tcells. As a result, life-threatening infections and a pronounced growth disorder can quickly develop. If left untreated, SCID and severe T-cell lymphopenia can lead to death. There are also mild forms known, which affect patients less significantly. With a stem cell transplant, SCID and severe Tcell lymphopenia can be cured. Patients who are diagnosed during newborn screening have a good prognosis.
Spinal muscular atrophy (SMA)
SMA is a rare congenital disease. People living with SMA experience a loss of nerve cells that are necessary for movement and muscle strength in the whole body. This leads to weakness in the muscles of the arms and legs. Breathing and swallowing can be severely affected during the course of the disease. Symptoms often become apparent in the first year of life. Newborn screening can identify almost all newborns (approx. 95%) at risk of SMA. If the test is positive, the parents are invited to a neuromuscular center for an urgent examination of the newborn and additional tests. Diagnosis after newborn screening allows for early monitoring and treatment. Effective therapies are now available that can halt or slow the progression of SMA. If treatment begins before the first symptoms appear, the baby has the best chance of normal motor development.